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'''[[Main Page|Home]] * [[Organizations]] * [[ICGA]] * [[ICGA Investigations|Investigations]] * Rybka Controversy'''
Allegations have surfaced that [[Rybka|Rybka 1.0 beta]] <ref>[http://www.chess.com/download/view/rybka-beta-10 Rybka 1.0 beta]</ref> and other versions of Rybka are derivatives of [[Fruit|Fruit 2.1]] and [[Crafty]]. If versions of Rybka are derived from Fruit and participated in ICGA tournaments, then Rybka has violated [[ICGA Tournament Rules]]. Fruit 2.1 <ref>[http://arctrix.com/nas/chess/fruit/ Fruit 2.1]</ref> source code was distributed with a [https://icga.wikispaces.com/fruit+copying.txt specific license]. Part of this license reads "For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights." Allegations state that by distributing Rybka which is based on Fruit, this GNU license was violated. The ICGA rules state "Programming teams whose code is derived from or including game-playing code written by others must name all other authors, or the source of such code, in the details of their submission form.". No such notification was included in the Rybka entry forms.
=Timeline=
==Wegner==
[[Zach Wegner]] analyzed the Rybka 1.0 beta exe file and noted many similarities in the two program's evaluation functions:
* [[File:ZW_Rybka_Fruit.pdf]]
==Letouzey==
On Jan 23, 2011, [[Fabien Letouzey]], author of Fruit, sent a letter to [[Tord Romstad]] about [[Strelka]] and Rybka <ref>[http://www.talkchess.com/forum/viewtopic.php?t=37762 Fabien's open letter to the community] by [[Tord Romstad]], [[CCC]], January 23, 2011</ref>
* [[Fabien Rybka Letter|Copy of the letter]]
==Watkins==
[[Mark Watkins]] also analysed Rybka 1.0 beta and details even more similarities:
* [[File:RYBKA_FRUIT_Mar11.pdf]]
* Annotated version of 64-bit evaluation function:
: [[File:R1x64eval.txt]]
==Levy==
On February 19, 2011 [[ICGA]] president [[David Levy]] broached on [[Clones|cloning]] issues in a ''ChessVibes'' column <ref>[http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011</ref>.
==Programmers==
In March 2011, following computer chess programmers signed an [[Open letter to the ICGA about the Rybka-Fruit issue|open letter]] to [[David Levy]], [[Jaap van den Herik]] and the [[Who's Who#ICGABoard|Board of the ICGA]], to support the claim [[Rybka|Rybka 1.0 beta]] and subsequent versions were allegedly derivatives from [[Fabien Letouzey|Fabien Letouzey’s]] program [[Fruit|Fruit 2.1]]:
* [[Fabien Letouzey]]
* [[Zach Wegner]]
* [[Mark Uniacke]]
* [[Stefan Meyer-Kahlen]]
* [[Ed Schroder|Ed Schröder]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref>
* [[Don Dailey]]
* [[Christophe Théron]]
* [[Richard Pijl]]
* [[Amir Ban]]
* [[Anthony Cozzie]]
* [[Tord Romstad]]
* [[Ralf Schäfer]]
* [[Gerd Isenberg]]
* [[Johannes Zwanzger]]
* [[Shay Bushinsky]]
* [[Volker Böhm]]
The letter was published in the private [[ICGA Investigations|ICGA Investigations Wiki]] <ref>[http://icga.wikispaces.com/ ICGA Investigations Wiki]</ref> and elsewhere <ref>[http://www.chessvibes.com/?q=reports/programmers-write-open-letter-about-rybka-fruit-issue Programmers write open letter about Rybka-Fruit issue : ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], March 01, 2011</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1175 Programmers Open Letter to ICGA on Rybka/Fruit] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 01, 2011</ref>. The German sites [http://de.wikipedia.org/wiki/Heise_online Heise online] <ref>[http://www.heise.de/newsticker/meldung/Plagiatsvorwurf-gegen-Computerschach-Weltmeister-1200222.html Plagiatsvorwurf gegen Computerschach-Weltmeister], [http://de.wikipedia.org/wiki/Heise_online Heise online], March 01, 2011 (German)</ref> and [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online] broached the issue <ref>[http://www.spiegel.de/netzwelt/gadgets/0,1518,748616,00.html Schach-Software Rybka - Programmierer vermuten Intelligenzklau] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], March 03, 2011 (German)</ref>.
=Pre-History of Rybka=
==2003==
About March or April 2003, Rajlich starts work on Rybka (see [[Vasik Rajlich#Conversation|interview]] by [[Nelson Hernandez]]).
==2004==
In January, Rybka competed in [[CCT6]], the largest online author-based tournament (a posting of Rajlich's from time gives a "Rybka 1.3" as a version number). In April, Rybka 1.5 enters the privately-run author-based tournaments Chess War V and Le Systeme du Saison. In October(?), Rybka 1.6 enters Chess War VI and AEGT 3. Rybka 1.6 also competed in Chess War VII.
There is ample [[pre-fruit Rybka and Crafty|evidence]] that the latter two versions contained large amounts of Crafty code, in direct contravention of both the relevant Crafty license and the rules of these tournaments. Based on the last tournament pre-Rybka played in, its rating was about 2064 ELO <ref>[http://www.open-aurec.com/chesswar/Chesswar007/Chesswar007CSt.htm ChessWar VII C 40m/20' - Final standings after round 11]</ref>.
==Fruit 2.1==
Fruit 2.1 was released in June 2005. For the purposes of ''prima facie'' evidence, it is necessary to establish that Rajlich obtained a copy. This can be inferred from his own words: ''I went through the Fruit 2.1 source code forwards and backwards and took many things.''
=History of Rybka 1.0 and beyond=
==2005==
* Rybka 1.0 Beta is released Dec 5 as a free download, and after a week the "Rybka 1" series becomes available on a subscription basis. About 13 "beta" versions of Rybka 1.0.1 were released over the next few months. Rybka 1.0.1-Beta-(x)? competed (as Rybka beta) and won first place in [[IPCCC 2005 b|Paderborn]] (December 27 2005) <ref>[http://forums.ubi.com/eve/forums/a/tpc/f/760105752/m/2741073293 Rybka Wins Paderborn 2005 !!! - Topic Powered by Social Strata]</ref>.
* The first commercial version, ''Rybka 1'' end of 2005.
==2006==
* On June 10 (date from RybkaChess FAQ about Rybka 2.x), the MP-only Rybka 2.0 Beta is released. The date on various executables are Apr 23 (Beta 8) and May 17 (Beta 4).
* Rybka (under the name Rajlich) competed in the [[WCCC 2006|2006]] ICGA Chess Tournament <ref>[https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=16 14th World Computer Chess Championship - Turin 2006 (ICGA Tournaments)]</ref>
* Rybka 2.1 was released Jul 26, 2006.
* Rybka 2.2 was released Nov 10, 2006.
* Rybka 2.2n2 was released Dec 14, 2006. All these dates are from the RybkaChess FAQ about Rybka 2.x (though that page seems to disappear every now and then).
==2007==
* Rybka 2.3 was released in late Feb 2007 (?). There was an "LK" version that had minor differences.
* A few more "2.3.1 beta" versions also appeared around this time (again including [[Larry Kaufman|Kaufman's]] latest material imbalance numbers). The Rybka 2.3 evaluation function appears to retain the numerology from Rybka 1.0 Beta. Rybka 2.3.1 starts to make a few changes (due to Kaufman?) in the numbers, though keeping the structure largely intact.
* Rybka 2.3.2 was released Jun 13, 2007, and 2.3.2a about 5 days later.
==Won ICGA Tournaments==
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=173 15th World Computer Chess Championship - Amsterdam 2007 (ICGA Tournaments)] » [[WCCC 2007]]
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=178 16th World Computer Chess Championship - Beijing 2008 (ICGA Tournaments)] » [[WCCC 2008]]
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=192 17th World Computer Chess Championship - Pamplona 2009 (ICGA Tournaments)] » [[WCCC 2009]]
* [[WCCC 2010]] <ref>[http://www.jaist.ac.jp/ICGA-events-2010/info/program.pdf WCCC 2010 program] (pdf)</ref>
==Later Rybkas==
There is still investigation to be done concerning what was in these later Rybkas.
The evaluation function in Rybka 2.3 (late Feb 2007, as above) looks to be that of Rybka 1.0 Beta (the executable contains many variants of the eval function, which seem to be either obfuscation or optimisation -- for instance, rook eval is dropped in one, so maybe if there are no rooks on the root position, this path would be taken).
Here is a raw dump of the eval, with annotations to be added <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1281 History of eval changes in Rybka versions] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 23, 2011</ref>:
: [[file:R230eval.txt]]
===Evaluation===
Here is my list of differences in eval between Rybka 2.3 (mid Feb 2007) and Rybka 1.0 Beta. As with some other Rybka versions, there are multiple "versions" of the eval function (e.g., some might ignore rooks) which might be due to some sort of optimisations (e.g. no rooks in root position).
* The 1-3-5-10 material weighting is multiplied by 3717 rather than 3399.
* The material imbalance adjustments are slightly perturbed. It seems that Rybka 2.2mp (Oct 31 2006) still had the same material imbalances as Rybka 1.0 Beta, but 2.2n2 (Dec 2 2006) differed (this version also is the first I can find to have 3717 rather than 3399).
* lazy eval has some sort of "positional evaluation" incrementation (likely changed fairly early in the Rybka series).
* The 3-centipawn tempo bonus was removed (not sure when - Rybka 2.1o had a 10-centipawn bonus, in some eval funcs).
* PawnFile PST is now [-4,-1,0,+1,+1,0,-1,-4] rather than -3 on a/h files.
* Drawishness from pawn files was added (already in Rybka 1.2, maybe earlier).
* The opening/endgame interpolation is now linear.
Everything else (including numerology and computation methods) seems the same in Rybka 2.3 and Rybka 1.0 Beta.
There are minor differences in the SWAR-based popcnt method, which could be just a different choice of compiler. Similarly, part of the mobility computations with lazy-eval seems to be inlined.
I think it is safe to say that very little work was done on the Rybka eval from Dec 2005 to somewhere around late 2006 or early 2007 (when Kaufman was hired).
* The evaluation function of Rybka 2.3.2a contains a few modifications, presumably due to Kaufman. Partially annotated version of Rybka 2.3.2a 64-bit evaluation function
: [[file:Ryb232eval.txt]]
* This document aligns the evaluations of Rybka 1.0 beta and Rybka 2.3.2a, showing nearly identical evaluation features (with some minor additions and tunings to 2.3.2a):
: [[file:RybkaEvalCompare.pdf]]
* Here is the "iterative deepening" part of the root search in Rybka 2.3.2a, to be compared to latter half of the function (starting with the easy move check) in Appendix A of the PDF:
: [[file:Ryb232a.iter.txt]]
===Comparisons with other Engines===
A detailed comparison of Rybka 1.0 and 2.3.2a versus other chess engines shows about a 1 in 10^12 or more chance of [[Quantifying Evaluation Features|evaluation overlap]] occurring "randomly"
[[file:EVAL_COMP.pdf]]
=Claims and Evidence=
* [[Claims of Rybka Originality]]
* [[Claims that Strelka is Rybka]]
* [[Pre-Fruit Rybka and Crafty]]
** [[Rybka-Crafty Evidence]] - re-use of code to tablebase use in KP vs KP when ''en passant'' was possible
** [[Rybka-Crafty Evidence II]] - checking whether the return value of EvaluateMate() was 99999
** [[Rybka-Crafty Evidence III]] - repeated zeroing of an element in a pawn hash structure
** [[Rybka-Crafty Evidence IV]] - the first part of the Evaluation functions
** [[Rybka-Crafty Evidence V]] - the EvaluateWinner() function
** [[Rybka-Crafty Evidence VI]] - NextMove() and NextEvasions() functions
<span id="Report"></span>
=Summary Report=
The Summary Report on the Rybka Controversy prepared by the secretariat, can be found here:
[[file:RybkaInvestigation.pdf]]
This report has been sent by [[David Levy]] to [[Vasik Rajlich]], asking him to provide comments. [[Who's Who|Panel members]] are reminded to keep this report private to allow Vasik Rajlich a chance to respond. It is expected sometime in the future this summary will be made public <ref>Statement from May 12, 2011, public since June 28, 2011</ref>.
Note from the Summary Report concerning ''Rybka 3'' [[Evaluation]] co-developer [[Larry Kaufman]]:
{| class="wikitable"
|-
| Note: Larry Kaufman is a Grandmaster long associated with helping programmers improve chess engines. There is absolutely no suspicion or belief on the part of the investigation panel or the ICGA that Kaufman has been in any way involved in any aspect of the copying behavior alleged of Vasik Rajlich. So far as the panel secretariat and the ICGA are concerned Kaufman’s reputation in this respect is squeaky clean
|}
<span id="RybkaDecision"></span>
=Decision concerning Rybka=
The final decision on the [[Rybka]] case by the [[Who's Who#ICGABoard|ICGA Board]], June 28, 2011: ''Rybka [[World Computer Chess Championship#RybkaDisqualification|disqualified]] and banned from [[World Computer Chess Championship|World Computer Chess Championships]]'' <ref>[http://www.chessvibes.com/?q=reports/rybka-disqualified-and-banned-from-world-computer-chess-championships Rybka disqualified and banned from World Computer Chess Championships | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], June 29, 2011</ref> <ref>[http://open-chess.org/viewtopic.php?f=3&t=1466 The ICGA Process] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], July 01, 2011</ref> <ref>[http://ilk.uvt.nl/icga/ ICGA Home Page]</ref>.
'''Rybka Disqualified and Banned from World Computer Chess Championships'''
The International Computer Games Association (ICGA) has been conducting an investigation into allegations that, in the chess program [[Rybka]], the programmer [[Vasik Rajlich]] plagiarized two other programs: [[Crafty]] and [[Fruit]]. The ICGA has considered and evaluated the evidence presented to the investigation panel and the report prepared by the panel’s Secretariat. (The report and evidence files are attached.) We would like to thank those members of the panel who contributed to this investigation and the Secretariat for the enormous amount of conscientious work they have put in to this matter.
By a unanimous 5-0 decision of executive members of the ICGA we find ourselves in agreement with the verdict of the Secretariat’s report. We are convinced that the evidence against Vasik Rajlich is both overwhelming in its volume and beyond reasonable question in its nature. Vasik Rajlich is guilty of plagiarizing the programs Crafty and Fruit, and has violated the [[ICGA Tournament Rules|ICGA’s tournament rules]] with respect to the [[World Computer Chess Championship|World Computer Chess Championships]] in the years [[WCCC 2006|2006]], [[WCCC 2007|2007]], [[WCCC 2008|2008]], [[WCCC 2009|2009]] and [[WCCC 2010|2010]]. Specifically, Vasik Rajlich, on all five occasions, violated Tournament Rule 2 which requires that:
{| class="wikitable"
|-
| Each program must be the original work of the entering developers. Programming teams whose code is derived from or including game-playing code written by others must name all other authors, or the source of such code, in their submission details. Programs which are discovered to be close derivatives of others (e.g., by playing nearly all moves the same), may be declared invalid by the Tournament Director after seeking expert advice. For this purpose a listing of all game-related code running on the system must be available on demand to the Tournament Director.
|}
By claiming other programmers’ work as his own, and failing to comply with the above mentioned rule, Vasik Rajlich has unfairly been awarded one shared 2nd-3rd place (in 2006) and four World Computer Chess Championship titles (in 2007, 2008, 2009 and 2010). Furthermore, it seems to the ICGA that Vasik Rajlich clearly knew that he was in the wrong in doing so, since he has repeatedly denied plagiarizing the work of other programmers.
The ICGA regards Vasik Rajlich’s violation of the above mentioned rule as the most serious offence that a chess programmer and ICGA member can commit with respect to his peers and to the ICGA. During the course of the investigation and upon presentation of the Secretariat’s report Vasik Rajlich did not offer, despite repeated invitations from the ICGA to do so, any kind of defence to the allegations, or to the evidence, or to the Secretariat’s report, other than to claim in an e-mail to myself on May 13th 2011 that:
* Rybka has does not “include game-playing code written by others”, aside from standard exceptions which wouldn’t count as ‘game-playing’.
* The vague phrase “derived from game-playing code written by others” also does not in my view apply to Rybka.
The ICGA is of the view that such a serious offence deserves to be met with correspondingly serious sanctions against the perpetrator. In deciding on appropriate sanctions the ICGA has borne in mind the approach of the International Olympic Committee for dealing with the most serious cases of the violations of its rules.
'''The ICGA has therefore decided as follows''':
* Vasik Rajlich is hereby disqualified from the [[World Computer Chess Championship|World Computer Chess Championships]] (WCCC) of [[WCCC 2006|2006]], [[WCCC 2007|2007]], [[WCCC 2008|2008]], [[WCCC 2009|2009]] and [[WCCC 2010|2010]].
* The 2nd-3rd place awarded to the program called “Rajlich” in the 2006 WCCC is hereby annulled, sole 2nd place is awarded to the program [[Shredder]], and 3rd place in that event is awarded to the program [[Zappa]].
* The 1st places and World Computer Chess Champion titles awarded to the program Rybka in the 2007, 2008, 2009 and 2010 WCCCs are hereby annulled, and all the other programs that competed in those events are moved up in the final tournament standings by one place. Thus the revised tournament standings and titles for those events will now be as follows.
<span id="2007"></span>
==2007==
* 1st [[Zappa]] (World Champion)
* 2nd [[Loop (Program)|Loop]]
* =3rd [[GridChess]]
* =3rd [[Shredder]]
<span id="2008"></span>
==2008==
* 1st [[Hiarcs]] (World Champion)
* 2nd [[Junior]]
* 3rd [[Cluster Toga]]
<span id="2009"></span>
==2009==
* =1st [[Junior]] (Joint World Champion)
* =1st [[Shredder]] (Joint World Champion)
* =1st [[Deep Sjeng]] (Joint World Champion)
<span id="2010"></span>
==2010==
* =1st [[Rondo]] (Joint World Champion)
* =1st [[Thinker]] (Joint World Champion)
* 3rd [[Shredder]]
In due course those programmers whose programs have been elevated to World Champion (or joint World Champion) status will receive from the ICGA replicas of the [[Shannon Trophy|Shannon trophy]] for the appropriate years.
The plaques on the Shannon trophy that currently bear the name Rybka (for the years 2007-2010) will be removed from the trophy and new plaques will be engraved with the names of the revised winners of the title.
Similarly, the titles of World Computer Speed (Blitz) Chess Champion that were awarded to Rybka in 2009 and 2010 are hereby annulled. The revised winners of the speed chess title for those years are therefore:
* 2009 [[Shredder]]
* 2010 [[Jonny]] and [[Shredder]] (joint champions)
Vasik Rajlich is banned for life from competing in the World Computer Chess Championship or any other event organized by or sanctioned by the ICGA.
The ICGA demands that Vasik Rajlich return to the ICGA the four replicas of the Shannon Trophy presented at the World Computer Chess Championships in 2007, 2008, 2009 and 2010, and to return to the ICGA all prize money awarded for Rybka’s performances in those events.
David Levy [President - ICGA]
June 28th 2011
----
=Aftermath=
After the ICGA decision, heated [[Computer Chess Forums|forum]] discussions arose. [[Chris Whittington]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22370 Minority Report Plagiarism - Quantifying Evaluation Features] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 09, 2011</ref> and [[Ed Schroder|Ed Schröder]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref> et al. criticize the ICGA investigation process, the work of the panel, and the ICGA decision. [[Sven Schüle]] <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=419368 Re: Crafty accused of copying Fruit PST] by [[Sven Schüle]], [[CCC]], August 15, 2011</ref>, [[Miguel A. Ballicora]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22572 PST Calculation] by [[Miguel A. Ballicora|michiguel]], [[Computer Chess Forums|Rybka Forum]], August 5, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22669 Take the Fruit Bishop tables...] by [[Miguel A. Ballicora|michiguel]], [[Computer Chess Forums|Rybka Forum]], August 16, 2011</ref>, [[Chris Whittington]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22642 A small detail about additive constants to PSTs] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 13, 2011 </ref>, [[Richard Vida]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22662 About PSQ tables] by [[Richard Vida]], [[Computer Chess Forums|Rybka Forum]], August 15, 2011</ref>, [[Mark Watkins]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1552 Fruit 1.0 PST] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 13, 2011</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1570 PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011</ref> and others elaborate and discuss [[Piece-Square Tables|Piece-Square Table]] matters <ref>[http://www.top-5000.nl/pst.htm PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Ed Schroder|Ed Schröder]]</ref>.
<span id="CSVN"></span>
==CSVN Decision==
In August 2011, the board of the Dutch Computer Chess Federation ([[CSVN]]) declared the most serious doubts as to the rightfulness of ICGA's decision. Therefore, they have chosen not to abide by their sanctions against Rybka <ref>[http://www.computerschaak.nl/index.php?option=com_content&view=article&id=514%3Arybka-en-de-icga&catid=18%3Avereniging&Itemid=28&lang=en Rybka and the ICGA], [http://www.csvn.nl/ CSVN Computerschaak]</ref> <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40151 Rybka to play in Leiden?] by [[Graham Banks]], [[CCC]], August 23, 2011</ref>:
{| class="wikitable"
|-
| Those who were in favour of the sanctions were severely questioned by (e.g.) [[Miguel A. Ballicora]], [[George Speight]] and [[Søren Riis]]. Their opposition did make an impression on us, because these people can rely upon a vast expertise in the field of chess programming, law and mathematical logic. When finally dutchman [[Ed Schroder|Ed Schröder]], former world computer chess champion, joined the aforementioned critics of ICGA, we no longer seemed to have a choice. <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref>
|}
==Open Letter==
At September 21, 2001, 15 former participants (14 program authors), [[Amir Ban]], [[Don Dailey]], [[Robert Hyatt]], [[Gerd Isenberg]], [[Marcel van Kervinck]], [[Stefan Meyer-Kahlen]], [[Fabien Letouzey]], [[Thomas Mayer]], [[Daniel Mehrmann]], [[Gian-Carlo Pascutto]], [[Richard Pijl]], [[Ralf Schäfer]], [[Mark Uniacke]], [[Ben-Hur Carlos Vieira Langoni Junior|Ben-Hur Carlos Vieira Langoni Júnior]], and [[Harvey Williamson]] signed an open letter to the [[CSVN]] and its board - to protest against their decision to ignore the [[ICGA]] suggestion and to allow Rybka playing their tournaments, the [[Dutch Open Computer Chess Championship]] and the [[International CSVN Tournament]], and declared they will no longer enter these tournaments under the current CSVN direction <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40489 Fwd: Open letter to the CSVN] by [[Marcel van Kervinck]], [[CCC]], September 21, 2011, on behalf of the signees</ref>.
==Different Views==
In November 2011, [[Ed Schroder|Ed Schröder]] announced his new web-sites <ref>[http://www.top-5000.nl/Rybka.htm Rybka vs ICGA a different view] by [[Ed Schroder|Ed Schröder]], November 09, 2011</ref> <ref>[http://www.top-5000.nl/evidence.htm Rybka evidence] by [[Ed Schroder|Ed Schröder]], November 09, 2011</ref> summarizing his alternative view of the historic ICGA - RYBKA event that led to the ban of [[Rybka]] and [[Vasik Rajlich]]. Short later, in January 2012, [[ChessBase]], a Rybka distributer, took a stand, publishing an article series in four parts by Danish mathematician and [[Computer Chess Forums|Rybka Forum]] moderator [[Søren Riis]] on their site - ''[[Søren Riis#Miscarriage|A Gross Miscarriage of Justice in Computer Chess]]'', also published as pdf <ref>[[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]</ref>.
<span id="Litmustest"></span>
==Litmus Test?==
Among other things matter of counter critic on Riis' article <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1763&p=15497#p15459 Re: Hyatt Is Gone!] by [[Mark Watkins|BB+]] [[Computer Chess Forums|OpenChess Forum]], Jan 03, 2012</ref>, the nasty <span style="background-color: #e5e5e5;">>= 0.0</span> match from Rybka's integer based - with Fruit's [[Float|float]] based time control code was declared a [https://en.wikipedia.org/wiki/Litmus litmus test] of the whole topic <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7811 A Gross Miscarriage of Justice in Computer Chess (part three)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 04, 2012 » Dots amazing: the case of the errant ‘0.0’</ref>. It was argued it could be a simple typo with only one additional trailing dot behind the zero. ‘0.’ already quantifies as float constant in [[C]] to force some compiler to emit the suspicious x87 instructions. Considering on how many places a chess program branches on the sign of an integer with <span style="background-color: #e5e5e5;">>= 0</span> or <span style="background-color: #e5e5e5;">< 0</span>, it is peculiar that the typo happened exactly there, in that time control code where Fruit has ‘0.0’. However, [[Miguel A. Ballicora]] found the initial float condition was different in Rybka, not <span style="background-color: #e5e5e5;">>= 0.0</span> but <span style="background-color: #e5e5e5;">> 0.0</span>, as published and mentioned by [[Ed Schroder|Ed Schröder]] in February 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=449909&t=42248 Re: Rybka 1.0 source code] by [[Ed Schroder|Ed Schröder]], [[CCC]], February 12, 2012</ref> <ref>[http://www.top-5000.nl/fadden.htm Did Vasik really copied Fruit's time control ?]</ref>. The different <span style="background-color: #e5e5e5;">> 0.0</span> condition was missed by the ICGA investigation panel, and implies the one and only possible literal copied line of Fruit code was at least modified.
<span id="Rebuttal"></span>
==Rebuttal==
At January 08, 2012 the [[ICGA]] responds with two rebuttal articles on [[Søren Riis|Riis']] ''[[Søren Riis#Miscarriage|A Gross Miscarriage of Justice in Computer Chess]]'', with an introduction letter from [[David Levy]], President of the ICGA <ref>[http://www.talkchess.com/forum/viewtopic.php?t=41866 ICGA response to ChessBase 4-part article] by [[Robert Hyatt]], [[CCC]], January 08, 2012</ref> <ref>[http://www.chessvibes.com/?q=reports/controversy-over-rybkas-disqualification-and-ban-update Controversy over Rybka's disqualification and ban (UPDATE) | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], January 08, 2012</ref> <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7836 Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012</ref>:
{| class="wikitable"
|-
| This week Dr Soren Riis posted a four part article on Chessbase.com in a somewhat belated attempt to defend [[Vasik Rajlich]]. Regular readers will recall that Rajlich's actions led the International Computer Games Association (ICGA) to find him guilty of breaking a crucial tournament rule, as a result of which the chess program Rybka was stripped of its World
Computer Chess Champion titles and Rajlich was banned for life from ICGA events.
Dr Riis gave his article a title to suggest that a miscarriage of justice has taken place. The ICGA now responds with two rebuttal articles, one by myself <ref>[[David Levy]] ('''2012'''). ''No Miscarriage of Justice - Just Biased Reporting''. [http://www.harveywilliamson.com/ICGA/DL_Rebuttal_to_Riis_article.January7th2012.doc doc]</ref> (as President of the ICGA) concerning some of the legalistic points raised by Riis's article, and a robust detailed and thorough technical rebuttal by [[Mark Watkins]] <ref>[[Mark Watkins]] ('''2012'''). ''A Critical Aanalysis of the four parts of Riis''. [http://harveywilliamson.com/ICGA/Riis3.pdf pdf]</ref>.
Everyone interested in the Rybka scandal should read both of these rebuttals and then decide for themselves who and what they believe - Dr Riis or the ICGA's investigation report.
Dr David Levy
President - ICGA
|}
<span id="FIDE"></span>
==FIDE==
In early 2012, the [[FIDE]] Ethics Commission <ref>[http://www.chessbase.com/newsdetail.asp?newsid=3844 Roberto Rivello: How the FIDE Ethics Commission works], [[ChessBase|ChessBase News]], May 11, 2007</ref> received a complaint signed by [[Vasik Rajlich]], co-signed by [[Søren Riis]], [[Chris Whittington]] and [[Ed Schroder|Ed Schröder]], against the [[ICGA]]. As announced at July 01, 2012, additional information is requested and the FIDE <ref>[http://www.fide.com/images/stories/NEWS_2012/FIDE/FIDE_Ethics_Commission_Decisions.pdf FIDE Ethics Commission ... during the meeting held in Lausanne on 30th June – 1st July 2012, assumed the following ... case 2/2012] (pdf)</ref>. Secretariat will communicate the decision to the complainants. The decision was made in April 2014. Parties are not allowed to publish the judgement as a whole, but may quote from it <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30056 Initiative in Stockfish vs. Crafty] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], April 07, 2015
[[Robert Hyatt|Bob]], 2015-04-20: [[FIDE]] has said this ...
[[Chris Whittington|Trotsky]], 2015-04-20: Strange. Do we have the same copy of the FIDE EC decision?</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30118 Complaint to FIFE Ethics Commission] by [[Lukas Cimiotti]], [[Computer Chess Forums|Rybka Forum]], April 24, 2015</ref>.
=See also=
* [[Open letter to the ICGA about the Rybka-Fruit issue]]
* [[Pre-Fruit Rybka and Crafty]]
* [[Quantifying Evaluation Features]]
=Publications=
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=272 pdf, February 12, 2011 Version] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1104 Feb 12 version: Rybka 1.0 Beta / Fruit 2.1 document] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 12, 2011</ref>
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=304 pdf, February 24, 2011 Version]
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=332 pdf, March 11, 2011 Version]
* [[Anthony Cozzie]] ('''2011'''). ''The Future of Computer Chess''. [[Selective Search]] 154, pp. 11, [http://www.chesscomputeruk.com/SS_154.pdf pdf] hosted by [[Mike Watters]]
* [[Jaap van den Herik]], [[Krzysztof Siewicz]] ('''2011'''). ''Open Source has a Price''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[David Levy]] ('''2011'''). ''Rybka Disqualified and Banned from World Computer Chess Championships''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[David Levy]] ('''2011'''). ''A Very Sad Case''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[Mark Lefler]], [[Robert Hyatt]], [[Harvey Williamson]], [[Who's Who|ICGA panel]] ('''2011'''). ''Rybka Investigations and Survey of Findings for the ICGA''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
: [[file:RybkaInvestigation.pdf]]
* [[Eric Hallsworth]] ('''2011'''). ''Rybka disqualified and banned by ICGA from World Computer Chess Championships, Lifetime Ban for Vasik Rajlich''. [[Selective Search]] 155, pp. 8, [http://www.chesscomputeruk.com/SS_155.pdf pdf] hosted by [[Mike Watters]]
* [[Mark Watkins]] ('''2011'''). ''Review of the Rybka case''. [http://www.open-chess.org/download/file.php?id=489 pdf] from [[Computer Chess Forums|OpenChess Forum]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1772 Rybka evidence recapitulation] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 03, 2012</ref>
* [[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]
* [[David Levy]] ('''2012'''). ''No Miscarriage of Justice - Just Biased Reporting''. [http://www.harveywilliamson.com/ICGA/DL_Rebuttal_to_Riis_article.January7th2012.doc doc]
* [[Mark Watkins]] ('''2012'''). ''A Critical Aanalysis of the four parts of Riis''. [http://harveywilliamson.com/ICGA/Riis3.pdf pdf]
* [[Ed Schroder|Ed Schröder]] ('''2012'''). ''Rybka reloaded''. [http://www.top-5000.nl/Rybka%20Reloaded.pdf pdf]
* [[Mark Watkins]] ('''2013'''). ''Review of the Rybka case''. [http://magma.maths.usyd.edu.au/~watkins/papers/RybkaRecap.pdf pdf]
* [[Jaap van den Herik]], [[Aske Plaat]], [[David Levy]], [[Daniel Dimov]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952114000093 Plagiarism in Game Programming Competitions]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3, [http://askeplaat.files.wordpress.com/2013/01/the-application-of-the-icga-rules-v15.pdf pdf preprint]
* [[Søren Riis]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952114000159 What makes a chess program original? Revisiting the Rybka case]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3
* [[Don Dailey]], [[Adam Hair]], [[Mark Watkins]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952113000177 Move Similarity Analysis in Chess Programs]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3, [http://magma.maths.usyd.edu.au/~watkins/papers/DHW.pdf preprint as pdf] <ref>[http://www.top-5000.nl/clone.htm A Pairwise Comparison of Chess Engine Move Selections] by [[Adam Hair]], hosted by [[Ed Schroder|Ed Schröder]]</ref>
* [[David Levy]] ('''2014'''). ''The RYBKA Case – Progress and Verdict''. [[ICGA Journal#37_4|ICGA Journal, Vol. 37, No. 4]]
* [[Ed Schroder|Ed Schröder]] ('''2015'''). ''The myth Rajlich copied Fruit''. [http://www.top-5000.nl/The-myth-Rajlich-copied-Fruit.pdf pdf]
=Forum Posts=
<ref>some [[Computer Chess Forums|Rybka Forum]] posts seem to require registration</ref>
==2011==
* [http://www.open-chess.org/viewtopic.php?f=5&t=1004 Node counting] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 20, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=37762 Fabien's open letter to the community] by [[Tord Romstad]], [[CCC]], January 23, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1014 Fabien's open letter to the community] by [[Tord Romstad]], [[Computer Chess Forums|OpenChess Forum]], January 23, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1023 Revisiting Strelka/Rybka] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 25, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1104 Feb 12 version: Rybka 1.0 Beta / Fruit 2.1 document] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 12, 2011
* [http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011
* [http://www.chessvibes.com/?q=reports/programmers-write-open-letter-about-rybka-fruit-issue Programmers write open letter about Rybka-Fruit issue : ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], March 01, 2011
* [http://www.hiarcs.net/forums/viewtopic.php?t=4038 Open letter to the ICGA about the Rybka-Fruit issue] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], March 01, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1175 Programmers Open Letter to ICGA on Rybka/Fruit] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 01, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=21216 Rybka 1.6.1] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], March 13, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=38440 Longer Article] by [[Anthony Cozzie]], [[CCC]], March 17, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1281 History of eval changes in Rybka versions] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 23, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39520 Rybka disqualified and banned from World Computer Chess Cham] by Tim Chan, [[CCC]], June 29, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22232 Rybka disqualified and banned from World Computer Chess Cham] by TheHug, [[Computer Chess Forums|Rybka Forum]], June 29, 2011
* [http://hiarcs.net/forums/viewtopic.php?t=4264&sid=ec7a3d377b4ca501b364599914913668 Rybka disqualified and banned from WCCC] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], June 29, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1463 Rybka disqualified and banned from WCCC] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], June 29, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39531 Rybka ban thoughts] by [[Dann Corbit]], [[CCC]], June 29, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39544 My two cents on Rybka's disqualification] by [[Joona Kiiski]], [[CCC]], June 30, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39546 Dismissed with prejudice] by [[Dann Corbit]], [[CCC]], July 01, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39545 Voir Dire] by [[Dann Corbit]], [[CCC]], July 01, 2011 <ref>[https://en.wikipedia.org/wiki/Voir_dire Voir dire from Wikipedia]</ref>
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22265 Vas say something] by siam, [[Computer Chess Forums|Rybka Forum]], July 01, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1471 Progess (often) is ugly, a summary try] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|OpenChess Forum]], July 03, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39593 Is Rybka that needs ICGA or the opposite ?] by [[Marco Costalba]], [[CCC]], July 03, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1475 The Evidence against Rybka] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], July 04, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22337 Why did the ICGA ignore this advice?] by [[John Sidles]], [[Computer Chess Forums|Rybka Forum]], July 06, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22370 Minority Report Plagiarism - Quantifying Evaluation Features] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 09, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22402 Vasik Rajlich responds to his accusers] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], July 12, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1552 Fruit 1.0 PST] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 13, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1570 PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40854 Interesting reflection on a past statement] by [[Graham Banks]], [[CCC]], October 22, 2011
==2012==
* [http://www.open-chess.org/viewtopic.php?f=3&t=1771 ChessBase: A Gross Miscarriage of Justice in Computer Chess] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], January 02, 2012
* [http://www.open-chess.org/viewtopic.php?f=3&t=1771#p15455 Re: ChessBase: A Gross Miscarriage of Justice in Computer Chess] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 02, 2012
* [http://www.open-chess.org/viewtopic.php?f=3&t=1763&p=15497#p15459 Re: Hyatt Is Gone!] by [[Mark Watkins|BB+]] [[Computer Chess Forums|OpenChess Forum]], Jan 03, 2012
* [http://www.open-chess.org/viewtopic.php?f=5&t=1772 Rybka evidence recapitulation] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 03, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=41866 ICGA response to ChessBase 4-part article] by [[Robert Hyatt]], [[CCC]], January 08, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=23957 A Big Thanks and a Small Update] by [[Vasik Rajlich]], [[Computer Chess Forums|Rybka Forum]], January 08, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=23966 Re: Another question for Vas] by [[Vasik Rajlich]], [[Computer Chess Forums|Rybka Forum]], January 09, 2012
* [http://www.open-chess.org/viewtopic.php?f=5&t=1795 Fruit/Rybka timeline] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 09, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=41913 Rybka Investigation : Survey Of Evidence] by [[Adam Hair]], [[CCC]], January 10, 2012 <ref>[http://www.top-5000.nl/adamhair.htm The Rybka Investigation: A Survey Of Evidence From Both Perspectives] by [[Adam Hair]], January 2012, hosted by [[Ed Schroder|Ed Schröder]]</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=41968 CB: Feedback on the ICGA/Rybka disqualification scandal] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 Ted Summers], [[CCC]], January 13, 2012 <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7836 Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012</ref>
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=24065 Wiki-leaks] by [[Ed Schroder|Ed Schröder]], [[Computer Chess Forums|Rybka Forum]], January, 18, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=42078 "Fissure opens in chess AI scene" (Rob Beschizza/B] by [[Julien Marcel]], [[CCC]], January 20, 2012 <ref>[http://boingboing.net/2012/01/19/fissure-opens-in-chess-ai-scen.html Fissure opens in chess AI scene - Boing Boing] by [http://beschizza.com/ Rob Beschizza], January 19, 2012</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=42248 Rybka 1.0 source code] by [[Ed Schroder|Ed Schröder]], [[CCC]], January 31, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=24200 Andrew Dalke - copyright specialist] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], February 02, 2012 <ref>[http://www.dalkescientific.com/writings/diary/archive/ Andrew Dalke's Dairy archive]</ref>
* [http://www.open-chess.org/viewtopic.php?f=5&t=1869 On Dalke] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 19, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=25525 Rybka & ICGA at the FIDE Ethics Commission] by vesuvio, [[Computer Chess Forums|Rybka Forum]], August 17, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=25573 In Retrospect: What have we learned from ICCA vs Rybka?] by Bob Durrett, [[Computer Chess Forums|Rybka Forum]], August 25, 2012
==2013==
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27334 Copying vs. stealing, ideas vs. source code etc.] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], July 07, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27345 Bob: Harvey did most of the writing] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 22, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27356 Vas: could we have the final hearings in October or November], [[Computer Chess Forums|Rybka Forum]], July 26, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27350 Bob used as a tool to do the dirty job] by [[Jeroen Noomen|Jeroen]], [[Computer Chess Forums|Rybka Forum]], July 24, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27363 Open thread: a collection of Hyatt lies in the Rybka case] by [[Jeroen Noomen|Jeroen]], [[Computer Chess Forums|Rybka Forum]], July 27, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27389 Was pre-beta Rybka ever "released"?], [[Computer Chess Forums|Rybka Forum]], July 29, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27386 The jury, the judge and the prosecutor], [[Computer Chess Forums|Rybka Forum]], August 01, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27421 Engine crash / incorrect mate score ], [[Computer Chess Forums|Rybka Forum]], August 08, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27412 adult discussions ;-) ], [[Computer Chess Forums|Rybka Forum]], August 09, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27380 More Bob lies] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 31, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27416 R.V. about Rybka 1.0 beta vs Fruit 2.1] by [[Richard Vida]], [[Computer Chess Forums|Rybka Forum]], August 11, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27472 Asides and commentary on RV's decompilation and reports] by turbojuice1122, [[Computer Chess Forums|Rybka Forum]], August 20, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27490 Bob's suggested punishment] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 21, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27491 Complaining about formulas or ideas] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 21, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27489 The originality claim...] by [[Dann Corbit|user923005]], [[Computer Chess Forums|Rybka Forum]], August 23, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27509 Vas quotes and misquotes discussions] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 26, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27518 The ICGA tribunal, what went wrong] by [[Dann Corbit|user923005]], [[Computer Chess Forums|Rybka Forum]], August 28, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27539 Rule 2 interpretation] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 28, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27520 What does "copy" mean?] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 29, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27523 The obfuscation story] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 29, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27537 Crafty/Fruit projection] by Nick, [[Computer Chess Forums|Rybka Forum]], August 30, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27550 Occam's razor vs Hyatt's razor] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 01, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27637 Rook eval Rybka vs Fruit] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 16, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27725 ChessVibes article] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], October 01, 2013
==2015==
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30056 Initiative in Stockfish vs. Crafty] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], April 07, 2015
: [[Robert Hyatt|Bob]], 2015-04-20: [[FIDE]] has said this ...
: [[Chris Whittington|Trotsky]], 2015-04-20: Strange. Do we have the same copy of the FIDE EC decision?
* [http://www.open-chess.org/viewtopic.php?f=3&t=2808 FIDE Rules on ICGA - Rybka controversy] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], April 14, 2015
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30118 Complaint to FIFE Ethics Commission] by [[Lukas Cimiotti]], [[Computer Chess Forums|Rybka Forum]], April 24, 2015
* [http://www.talkchess.com/forum/viewtopic.php?t=56112 FIDE Ethics Commission ruling on ICGA/Rybka complaint] by [[Graham Banks]], [[CCC]], April 24, 2015
* [http://www.open-chess.org/viewtopic.php?f=3&t=2810 FIDE Ethics Commission dealings (Case 2/12)] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 24, 2015
=External Links=
* [http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011
* [http://www.spiegel.de/netzwelt/gadgets/schach-software-rybka-programmierer-vermuten-intelligenzklau-a-748616.html Schach-Software Rybka - Programmierer vermuten Intelligenzklau] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], March 03, 2011 (German)
* [https://www.heise.de/newsticker/meldung/Plagiatsvorwurf-gegen-Computerschach-Weltmeister-1200222.html Plagiatsvorwurf gegen Computerschach-Weltmeister], [http://de.wikipedia.org/wiki/Heise_online Heise online], March 01, 2011 (German)
* [http://www.chessvibes.com/?q=reports/rybka-disqualified-and-banned-from-world-computer-chess-championships Rybka disqualified and banned from World Computer Chess Championships | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], June 29, 2011
* [http://chess.business-news-blog.eu/2011/rybka-banned-by-international-games-federation-rybka-ruling/ Rybka banned by International Games Federation – Rybka Ruling]
* [http://www.extremetech.com/extreme/88610-rybka-the-worlds-best-chess-engine-outlawed-and-disqualified Rybka, the world’s best chess engine, outlawed and disqualified | ExtremeTech] by [http://www.mrseb.co.uk/ Sebastian Anthony] on June 29, 2011
* [https://m.washingtontimes.com/news/2011/jun/30/computer-chess-champ-stripped-of-its-four-titles/ Computer chess champ stripped of its four titles] by [http://www.linkedin.com/pub/claire-courchane/2a/857/3b Claire Courchane], [https://en.wikipedia.org/wiki/The_Washington_Times Washington Times], June 30, 2011
* [https://www.itproportal.com/2011/06/30/rybka-disqualified-banned-on-plagiarism-charges/ Rybka Disqualified, Banned On Plagiarism Charges | ITProPortal.com] by [http://www.itproportal.com/staff/ravimandalia/ Ravi Mandalia], June 30, 2011
* [http://boylston-chess-club.blogspot.com/2011/06/rybka-banned-from-computer-champs.html Boylston Chess Club Weblog: Rybka banned from computer champs; stripped of all its titles], June 30, 2011
* [https://metro.co.uk/2011/06/30/computer-chess-reels-from-biggest-sporting-scandal-since-ben-johnson-62543/ Computer chess reels from 'biggest sporting scandal since Ben Johnson' | Metro.co.uk] by [http://tariqtahir.com/ Tariq Tahir], June 30th, 2011
* [https://www.heise.de/newsticker/meldung/Schachcomputer-Weltmeister-nachtraeglich-disqualifiziert-1271033.html Schachcomputer-Weltmeister nachträglich disqualifiziert], [http://de.wikipedia.org/wiki/Heise_online Heise online], June 30, 2011 (German)
* [http://www.spiegel.de/netzwelt/games/plagiats-skandal-weltmeisterprogramm-rybka-verliert-alle-titel-a-771620.html Weltmeisterprogramm Rybka verliert alle Titel] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], July 01, 2011 (German)
* [https://www.nytimes.com/2011/07/03/crosswords/chess/developer-of-computer-chess-champ-accused-of-stealing-code.html?_r=1 Developer of Computer Chess Champ Accused of Stealing Code] by [https://topics.nytimes.com/top/reference/timestopics/people/m/dylan_loeb_mcclain/index.html?inline=nyt-per Dylan Loeb McClain], [https://en.wikipedia.org/wiki/The_New_York_Times NYTimes.com], July 02, 2011
* "Another Conversation with Vasik Rajlich" By [[Nelson Hernandez]] (on Rybka chess), July 04, 2011, [https://en.wikipedia.org/wiki/YouTube YouTube] Video <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22402 Vasik Rajlich responds to his accusers] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], July 12, 2011</ref>
: {{#evu:https://www.youtube.com/watch?v=cQshTNJ4pSM|alignment=left|valignment=top}}
* [https://diepresse.com/home/spectrum/spielundmehr/676421/Geklontes-Fischchen Geklontes Fischchen] by [[Stefan Löffler]], July 08, 2011, [http://diepresse.com/home/index.do DiePresse.com] (German)
* [http://www.top-5000.nl/Rybka.htm Rybka vs ICGA a different view] by [[Ed Schroder|Ed Schröder]], November 09, 2011
* [http://www.top-5000.nl/evidence.htm Rybka evidence] by [[Ed Schroder|Ed Schröder]], November 09, 2011
* [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-one A Gross Miscarriage of Justice in Computer Chess (part one)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 02, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-two A Gross Miscarriage of Justice in Computer Chess (part two)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 03, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-three A Gross Miscarriage of Justice in Computer Chess (part three)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 04, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-four A Gross Miscarriage of Justice in Computer Chess (part four)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 05, 2012 <ref>[[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]</ref>
* [http://www.chessvibes.com/?q=reports/controversy-over-rybkas-disqualification-and-ban-update Controversy over Rybka's disqualification and ban (UPDATE) | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], January 08, 2012
* [http://www.top-5000.nl/adamhair.htm The Rybka Investigation: A Survey Of Evidence From Both Perspectives] by [[Adam Hair]], January 2012, hosted by [[Ed Schroder|Ed Schröder]]
* [https://en.chessbase.com/post/feedback-on-the-icga-rybka-disqualification-scandal Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=41968 CB: Feedback on the ICGA/Rybka disqualification scandal] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 Ted Summers], [[CCC]], January 13, 2012</ref>
* [https://boingboing.net/2012/01/19/fissure-opens-in-chess-ai-scen.html Fissure opens in chess AI scene - Boing Boing] by [http://beschizza.com/ Rob Beschizza], January 19, 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=42078 "Fissure opens in chess AI scene" (Rob Beschizza/B] by [[Julien Marcel]], [[CCC]], January 20, 2012</ref>
* [https://en.chessbase.com/post/icga-rybka-controversy-an-interview-with-david-levy-1 ICGA/Rybka controversy: An interview with David Levy (1)], [[ChessBase|ChessBase News]], February 06, 2012
: [https://en.chessbase.com/post/icga-rybka-controversy-an-interview-with-david-levy-2 ICGA/Rybka controversy: An interview with David Levy (2)], [[ChessBase|ChessBase News]], February 10, 2012
* [https://en.chessbase.com/post/icga-rybka-controversy-feedback ICGA/Rybka controversy: Feedback], [[ChessBase|ChessBase News]], February 17, 2012
* [http://www.chessvibes.com/?q=rybka-case-greatest-injustice-perpetrated-in-computer-chess-history-part-1 Rybka case "greatest injustice perpetrated in computer chess history" (Part 1) | ChessVibes] by [[Ed Schroder|Ed Schröder]], October 01, 2013
: [http://www.chessvibes.com/?q=rybka-case-greatest-injustice-perpetrated-in-computer-chess-history-part-2 Rybka case "greatest injustice perpetrated in computer chess history" (Part 2) | ChessVibes] by [[Ed Schroder|Ed Schröder]], October 05, 2013
=References=
<references />
'''[[ICGA Investigations|Up one level]]'''
Allegations have surfaced that [[Rybka|Rybka 1.0 beta]] <ref>[http://www.chess.com/download/view/rybka-beta-10 Rybka 1.0 beta]</ref> and other versions of Rybka are derivatives of [[Fruit|Fruit 2.1]] and [[Crafty]]. If versions of Rybka are derived from Fruit and participated in ICGA tournaments, then Rybka has violated [[ICGA Tournament Rules]]. Fruit 2.1 <ref>[http://arctrix.com/nas/chess/fruit/ Fruit 2.1]</ref> source code was distributed with a [https://icga.wikispaces.com/fruit+copying.txt specific license]. Part of this license reads "For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights." Allegations state that by distributing Rybka which is based on Fruit, this GNU license was violated. The ICGA rules state "Programming teams whose code is derived from or including game-playing code written by others must name all other authors, or the source of such code, in the details of their submission form.". No such notification was included in the Rybka entry forms.
=Timeline=
==Wegner==
[[Zach Wegner]] analyzed the Rybka 1.0 beta exe file and noted many similarities in the two program's evaluation functions:
* [[File:ZW_Rybka_Fruit.pdf]]
==Letouzey==
On Jan 23, 2011, [[Fabien Letouzey]], author of Fruit, sent a letter to [[Tord Romstad]] about [[Strelka]] and Rybka <ref>[http://www.talkchess.com/forum/viewtopic.php?t=37762 Fabien's open letter to the community] by [[Tord Romstad]], [[CCC]], January 23, 2011</ref>
* [[Fabien Rybka Letter|Copy of the letter]]
==Watkins==
[[Mark Watkins]] also analysed Rybka 1.0 beta and details even more similarities:
* [[File:RYBKA_FRUIT_Mar11.pdf]]
* Annotated version of 64-bit evaluation function:
: [[File:R1x64eval.txt]]
==Levy==
On February 19, 2011 [[ICGA]] president [[David Levy]] broached on [[Clones|cloning]] issues in a ''ChessVibes'' column <ref>[http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011</ref>.
==Programmers==
In March 2011, following computer chess programmers signed an [[Open letter to the ICGA about the Rybka-Fruit issue|open letter]] to [[David Levy]], [[Jaap van den Herik]] and the [[Who's Who#ICGABoard|Board of the ICGA]], to support the claim [[Rybka|Rybka 1.0 beta]] and subsequent versions were allegedly derivatives from [[Fabien Letouzey|Fabien Letouzey’s]] program [[Fruit|Fruit 2.1]]:
* [[Fabien Letouzey]]
* [[Zach Wegner]]
* [[Mark Uniacke]]
* [[Stefan Meyer-Kahlen]]
* [[Ed Schroder|Ed Schröder]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref>
* [[Don Dailey]]
* [[Christophe Théron]]
* [[Richard Pijl]]
* [[Amir Ban]]
* [[Anthony Cozzie]]
* [[Tord Romstad]]
* [[Ralf Schäfer]]
* [[Gerd Isenberg]]
* [[Johannes Zwanzger]]
* [[Shay Bushinsky]]
* [[Volker Böhm]]
The letter was published in the private [[ICGA Investigations|ICGA Investigations Wiki]] <ref>[http://icga.wikispaces.com/ ICGA Investigations Wiki]</ref> and elsewhere <ref>[http://www.chessvibes.com/?q=reports/programmers-write-open-letter-about-rybka-fruit-issue Programmers write open letter about Rybka-Fruit issue : ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], March 01, 2011</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1175 Programmers Open Letter to ICGA on Rybka/Fruit] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 01, 2011</ref>. The German sites [http://de.wikipedia.org/wiki/Heise_online Heise online] <ref>[http://www.heise.de/newsticker/meldung/Plagiatsvorwurf-gegen-Computerschach-Weltmeister-1200222.html Plagiatsvorwurf gegen Computerschach-Weltmeister], [http://de.wikipedia.org/wiki/Heise_online Heise online], March 01, 2011 (German)</ref> and [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online] broached the issue <ref>[http://www.spiegel.de/netzwelt/gadgets/0,1518,748616,00.html Schach-Software Rybka - Programmierer vermuten Intelligenzklau] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], March 03, 2011 (German)</ref>.
=Pre-History of Rybka=
==2003==
About March or April 2003, Rajlich starts work on Rybka (see [[Vasik Rajlich#Conversation|interview]] by [[Nelson Hernandez]]).
==2004==
In January, Rybka competed in [[CCT6]], the largest online author-based tournament (a posting of Rajlich's from time gives a "Rybka 1.3" as a version number). In April, Rybka 1.5 enters the privately-run author-based tournaments Chess War V and Le Systeme du Saison. In October(?), Rybka 1.6 enters Chess War VI and AEGT 3. Rybka 1.6 also competed in Chess War VII.
There is ample [[pre-fruit Rybka and Crafty|evidence]] that the latter two versions contained large amounts of Crafty code, in direct contravention of both the relevant Crafty license and the rules of these tournaments. Based on the last tournament pre-Rybka played in, its rating was about 2064 ELO <ref>[http://www.open-aurec.com/chesswar/Chesswar007/Chesswar007CSt.htm ChessWar VII C 40m/20' - Final standings after round 11]</ref>.
==Fruit 2.1==
Fruit 2.1 was released in June 2005. For the purposes of ''prima facie'' evidence, it is necessary to establish that Rajlich obtained a copy. This can be inferred from his own words: ''I went through the Fruit 2.1 source code forwards and backwards and took many things.''
=History of Rybka 1.0 and beyond=
==2005==
* Rybka 1.0 Beta is released Dec 5 as a free download, and after a week the "Rybka 1" series becomes available on a subscription basis. About 13 "beta" versions of Rybka 1.0.1 were released over the next few months. Rybka 1.0.1-Beta-(x)? competed (as Rybka beta) and won first place in [[IPCCC 2005 b|Paderborn]] (December 27 2005) <ref>[http://forums.ubi.com/eve/forums/a/tpc/f/760105752/m/2741073293 Rybka Wins Paderborn 2005 !!! - Topic Powered by Social Strata]</ref>.
* The first commercial version, ''Rybka 1'' end of 2005.
==2006==
* On June 10 (date from RybkaChess FAQ about Rybka 2.x), the MP-only Rybka 2.0 Beta is released. The date on various executables are Apr 23 (Beta 8) and May 17 (Beta 4).
* Rybka (under the name Rajlich) competed in the [[WCCC 2006|2006]] ICGA Chess Tournament <ref>[https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=16 14th World Computer Chess Championship - Turin 2006 (ICGA Tournaments)]</ref>
* Rybka 2.1 was released Jul 26, 2006.
* Rybka 2.2 was released Nov 10, 2006.
* Rybka 2.2n2 was released Dec 14, 2006. All these dates are from the RybkaChess FAQ about Rybka 2.x (though that page seems to disappear every now and then).
==2007==
* Rybka 2.3 was released in late Feb 2007 (?). There was an "LK" version that had minor differences.
* A few more "2.3.1 beta" versions also appeared around this time (again including [[Larry Kaufman|Kaufman's]] latest material imbalance numbers). The Rybka 2.3 evaluation function appears to retain the numerology from Rybka 1.0 Beta. Rybka 2.3.1 starts to make a few changes (due to Kaufman?) in the numbers, though keeping the structure largely intact.
* Rybka 2.3.2 was released Jun 13, 2007, and 2.3.2a about 5 days later.
==Won ICGA Tournaments==
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=173 15th World Computer Chess Championship - Amsterdam 2007 (ICGA Tournaments)] » [[WCCC 2007]]
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=178 16th World Computer Chess Championship - Beijing 2008 (ICGA Tournaments)] » [[WCCC 2008]]
* [https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=192 17th World Computer Chess Championship - Pamplona 2009 (ICGA Tournaments)] » [[WCCC 2009]]
* [[WCCC 2010]] <ref>[http://www.jaist.ac.jp/ICGA-events-2010/info/program.pdf WCCC 2010 program] (pdf)</ref>
==Later Rybkas==
There is still investigation to be done concerning what was in these later Rybkas.
The evaluation function in Rybka 2.3 (late Feb 2007, as above) looks to be that of Rybka 1.0 Beta (the executable contains many variants of the eval function, which seem to be either obfuscation or optimisation -- for instance, rook eval is dropped in one, so maybe if there are no rooks on the root position, this path would be taken).
Here is a raw dump of the eval, with annotations to be added <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1281 History of eval changes in Rybka versions] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 23, 2011</ref>:
: [[file:R230eval.txt]]
===Evaluation===
Here is my list of differences in eval between Rybka 2.3 (mid Feb 2007) and Rybka 1.0 Beta. As with some other Rybka versions, there are multiple "versions" of the eval function (e.g., some might ignore rooks) which might be due to some sort of optimisations (e.g. no rooks in root position).
* The 1-3-5-10 material weighting is multiplied by 3717 rather than 3399.
* The material imbalance adjustments are slightly perturbed. It seems that Rybka 2.2mp (Oct 31 2006) still had the same material imbalances as Rybka 1.0 Beta, but 2.2n2 (Dec 2 2006) differed (this version also is the first I can find to have 3717 rather than 3399).
* lazy eval has some sort of "positional evaluation" incrementation (likely changed fairly early in the Rybka series).
* The 3-centipawn tempo bonus was removed (not sure when - Rybka 2.1o had a 10-centipawn bonus, in some eval funcs).
* PawnFile PST is now [-4,-1,0,+1,+1,0,-1,-4] rather than -3 on a/h files.
* Drawishness from pawn files was added (already in Rybka 1.2, maybe earlier).
* The opening/endgame interpolation is now linear.
Everything else (including numerology and computation methods) seems the same in Rybka 2.3 and Rybka 1.0 Beta.
There are minor differences in the SWAR-based popcnt method, which could be just a different choice of compiler. Similarly, part of the mobility computations with lazy-eval seems to be inlined.
I think it is safe to say that very little work was done on the Rybka eval from Dec 2005 to somewhere around late 2006 or early 2007 (when Kaufman was hired).
* The evaluation function of Rybka 2.3.2a contains a few modifications, presumably due to Kaufman. Partially annotated version of Rybka 2.3.2a 64-bit evaluation function
: [[file:Ryb232eval.txt]]
* This document aligns the evaluations of Rybka 1.0 beta and Rybka 2.3.2a, showing nearly identical evaluation features (with some minor additions and tunings to 2.3.2a):
: [[file:RybkaEvalCompare.pdf]]
* Here is the "iterative deepening" part of the root search in Rybka 2.3.2a, to be compared to latter half of the function (starting with the easy move check) in Appendix A of the PDF:
: [[file:Ryb232a.iter.txt]]
===Comparisons with other Engines===
A detailed comparison of Rybka 1.0 and 2.3.2a versus other chess engines shows about a 1 in 10^12 or more chance of [[Quantifying Evaluation Features|evaluation overlap]] occurring "randomly"
[[file:EVAL_COMP.pdf]]
=Claims and Evidence=
* [[Claims of Rybka Originality]]
* [[Claims that Strelka is Rybka]]
* [[Pre-Fruit Rybka and Crafty]]
** [[Rybka-Crafty Evidence]] - re-use of code to tablebase use in KP vs KP when ''en passant'' was possible
** [[Rybka-Crafty Evidence II]] - checking whether the return value of EvaluateMate() was 99999
** [[Rybka-Crafty Evidence III]] - repeated zeroing of an element in a pawn hash structure
** [[Rybka-Crafty Evidence IV]] - the first part of the Evaluation functions
** [[Rybka-Crafty Evidence V]] - the EvaluateWinner() function
** [[Rybka-Crafty Evidence VI]] - NextMove() and NextEvasions() functions
<span id="Report"></span>
=Summary Report=
The Summary Report on the Rybka Controversy prepared by the secretariat, can be found here:
[[file:RybkaInvestigation.pdf]]
This report has been sent by [[David Levy]] to [[Vasik Rajlich]], asking him to provide comments. [[Who's Who|Panel members]] are reminded to keep this report private to allow Vasik Rajlich a chance to respond. It is expected sometime in the future this summary will be made public <ref>Statement from May 12, 2011, public since June 28, 2011</ref>.
Note from the Summary Report concerning ''Rybka 3'' [[Evaluation]] co-developer [[Larry Kaufman]]:
{| class="wikitable"
|-
| Note: Larry Kaufman is a Grandmaster long associated with helping programmers improve chess engines. There is absolutely no suspicion or belief on the part of the investigation panel or the ICGA that Kaufman has been in any way involved in any aspect of the copying behavior alleged of Vasik Rajlich. So far as the panel secretariat and the ICGA are concerned Kaufman’s reputation in this respect is squeaky clean
|}
<span id="RybkaDecision"></span>
=Decision concerning Rybka=
The final decision on the [[Rybka]] case by the [[Who's Who#ICGABoard|ICGA Board]], June 28, 2011: ''Rybka [[World Computer Chess Championship#RybkaDisqualification|disqualified]] and banned from [[World Computer Chess Championship|World Computer Chess Championships]]'' <ref>[http://www.chessvibes.com/?q=reports/rybka-disqualified-and-banned-from-world-computer-chess-championships Rybka disqualified and banned from World Computer Chess Championships | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], June 29, 2011</ref> <ref>[http://open-chess.org/viewtopic.php?f=3&t=1466 The ICGA Process] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], July 01, 2011</ref> <ref>[http://ilk.uvt.nl/icga/ ICGA Home Page]</ref>.
'''Rybka Disqualified and Banned from World Computer Chess Championships'''
The International Computer Games Association (ICGA) has been conducting an investigation into allegations that, in the chess program [[Rybka]], the programmer [[Vasik Rajlich]] plagiarized two other programs: [[Crafty]] and [[Fruit]]. The ICGA has considered and evaluated the evidence presented to the investigation panel and the report prepared by the panel’s Secretariat. (The report and evidence files are attached.) We would like to thank those members of the panel who contributed to this investigation and the Secretariat for the enormous amount of conscientious work they have put in to this matter.
By a unanimous 5-0 decision of executive members of the ICGA we find ourselves in agreement with the verdict of the Secretariat’s report. We are convinced that the evidence against Vasik Rajlich is both overwhelming in its volume and beyond reasonable question in its nature. Vasik Rajlich is guilty of plagiarizing the programs Crafty and Fruit, and has violated the [[ICGA Tournament Rules|ICGA’s tournament rules]] with respect to the [[World Computer Chess Championship|World Computer Chess Championships]] in the years [[WCCC 2006|2006]], [[WCCC 2007|2007]], [[WCCC 2008|2008]], [[WCCC 2009|2009]] and [[WCCC 2010|2010]]. Specifically, Vasik Rajlich, on all five occasions, violated Tournament Rule 2 which requires that:
{| class="wikitable"
|-
| Each program must be the original work of the entering developers. Programming teams whose code is derived from or including game-playing code written by others must name all other authors, or the source of such code, in their submission details. Programs which are discovered to be close derivatives of others (e.g., by playing nearly all moves the same), may be declared invalid by the Tournament Director after seeking expert advice. For this purpose a listing of all game-related code running on the system must be available on demand to the Tournament Director.
|}
By claiming other programmers’ work as his own, and failing to comply with the above mentioned rule, Vasik Rajlich has unfairly been awarded one shared 2nd-3rd place (in 2006) and four World Computer Chess Championship titles (in 2007, 2008, 2009 and 2010). Furthermore, it seems to the ICGA that Vasik Rajlich clearly knew that he was in the wrong in doing so, since he has repeatedly denied plagiarizing the work of other programmers.
The ICGA regards Vasik Rajlich’s violation of the above mentioned rule as the most serious offence that a chess programmer and ICGA member can commit with respect to his peers and to the ICGA. During the course of the investigation and upon presentation of the Secretariat’s report Vasik Rajlich did not offer, despite repeated invitations from the ICGA to do so, any kind of defence to the allegations, or to the evidence, or to the Secretariat’s report, other than to claim in an e-mail to myself on May 13th 2011 that:
* Rybka has does not “include game-playing code written by others”, aside from standard exceptions which wouldn’t count as ‘game-playing’.
* The vague phrase “derived from game-playing code written by others” also does not in my view apply to Rybka.
The ICGA is of the view that such a serious offence deserves to be met with correspondingly serious sanctions against the perpetrator. In deciding on appropriate sanctions the ICGA has borne in mind the approach of the International Olympic Committee for dealing with the most serious cases of the violations of its rules.
'''The ICGA has therefore decided as follows''':
* Vasik Rajlich is hereby disqualified from the [[World Computer Chess Championship|World Computer Chess Championships]] (WCCC) of [[WCCC 2006|2006]], [[WCCC 2007|2007]], [[WCCC 2008|2008]], [[WCCC 2009|2009]] and [[WCCC 2010|2010]].
* The 2nd-3rd place awarded to the program called “Rajlich” in the 2006 WCCC is hereby annulled, sole 2nd place is awarded to the program [[Shredder]], and 3rd place in that event is awarded to the program [[Zappa]].
* The 1st places and World Computer Chess Champion titles awarded to the program Rybka in the 2007, 2008, 2009 and 2010 WCCCs are hereby annulled, and all the other programs that competed in those events are moved up in the final tournament standings by one place. Thus the revised tournament standings and titles for those events will now be as follows.
<span id="2007"></span>
==2007==
* 1st [[Zappa]] (World Champion)
* 2nd [[Loop (Program)|Loop]]
* =3rd [[GridChess]]
* =3rd [[Shredder]]
<span id="2008"></span>
==2008==
* 1st [[Hiarcs]] (World Champion)
* 2nd [[Junior]]
* 3rd [[Cluster Toga]]
<span id="2009"></span>
==2009==
* =1st [[Junior]] (Joint World Champion)
* =1st [[Shredder]] (Joint World Champion)
* =1st [[Deep Sjeng]] (Joint World Champion)
<span id="2010"></span>
==2010==
* =1st [[Rondo]] (Joint World Champion)
* =1st [[Thinker]] (Joint World Champion)
* 3rd [[Shredder]]
In due course those programmers whose programs have been elevated to World Champion (or joint World Champion) status will receive from the ICGA replicas of the [[Shannon Trophy|Shannon trophy]] for the appropriate years.
The plaques on the Shannon trophy that currently bear the name Rybka (for the years 2007-2010) will be removed from the trophy and new plaques will be engraved with the names of the revised winners of the title.
Similarly, the titles of World Computer Speed (Blitz) Chess Champion that were awarded to Rybka in 2009 and 2010 are hereby annulled. The revised winners of the speed chess title for those years are therefore:
* 2009 [[Shredder]]
* 2010 [[Jonny]] and [[Shredder]] (joint champions)
Vasik Rajlich is banned for life from competing in the World Computer Chess Championship or any other event organized by or sanctioned by the ICGA.
The ICGA demands that Vasik Rajlich return to the ICGA the four replicas of the Shannon Trophy presented at the World Computer Chess Championships in 2007, 2008, 2009 and 2010, and to return to the ICGA all prize money awarded for Rybka’s performances in those events.
David Levy [President - ICGA]
June 28th 2011
----
=Aftermath=
After the ICGA decision, heated [[Computer Chess Forums|forum]] discussions arose. [[Chris Whittington]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22370 Minority Report Plagiarism - Quantifying Evaluation Features] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 09, 2011</ref> and [[Ed Schroder|Ed Schröder]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref> et al. criticize the ICGA investigation process, the work of the panel, and the ICGA decision. [[Sven Schüle]] <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=419368 Re: Crafty accused of copying Fruit PST] by [[Sven Schüle]], [[CCC]], August 15, 2011</ref>, [[Miguel A. Ballicora]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22572 PST Calculation] by [[Miguel A. Ballicora|michiguel]], [[Computer Chess Forums|Rybka Forum]], August 5, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22669 Take the Fruit Bishop tables...] by [[Miguel A. Ballicora|michiguel]], [[Computer Chess Forums|Rybka Forum]], August 16, 2011</ref>, [[Chris Whittington]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22642 A small detail about additive constants to PSTs] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 13, 2011 </ref>, [[Richard Vida]] <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22662 About PSQ tables] by [[Richard Vida]], [[Computer Chess Forums|Rybka Forum]], August 15, 2011</ref>, [[Mark Watkins]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1552 Fruit 1.0 PST] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 13, 2011</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1570 PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011</ref> and others elaborate and discuss [[Piece-Square Tables|Piece-Square Table]] matters <ref>[http://www.top-5000.nl/pst.htm PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Ed Schroder|Ed Schröder]]</ref>.
<span id="CSVN"></span>
==CSVN Decision==
In August 2011, the board of the Dutch Computer Chess Federation ([[CSVN]]) declared the most serious doubts as to the rightfulness of ICGA's decision. Therefore, they have chosen not to abide by their sanctions against Rybka <ref>[http://www.computerschaak.nl/index.php?option=com_content&view=article&id=514%3Arybka-en-de-icga&catid=18%3Avereniging&Itemid=28&lang=en Rybka and the ICGA], [http://www.csvn.nl/ CSVN Computerschaak]</ref> <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40151 Rybka to play in Leiden?] by [[Graham Banks]], [[CCC]], August 23, 2011</ref>:
{| class="wikitable"
|-
| Those who were in favour of the sanctions were severely questioned by (e.g.) [[Miguel A. Ballicora]], [[George Speight]] and [[Søren Riis]]. Their opposition did make an impression on us, because these people can rely upon a vast expertise in the field of chess programming, law and mathematical logic. When finally dutchman [[Ed Schroder|Ed Schröder]], former world computer chess champion, joined the aforementioned critics of ICGA, we no longer seemed to have a choice. <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011</ref>
|}
==Open Letter==
At September 21, 2001, 15 former participants (14 program authors), [[Amir Ban]], [[Don Dailey]], [[Robert Hyatt]], [[Gerd Isenberg]], [[Marcel van Kervinck]], [[Stefan Meyer-Kahlen]], [[Fabien Letouzey]], [[Thomas Mayer]], [[Daniel Mehrmann]], [[Gian-Carlo Pascutto]], [[Richard Pijl]], [[Ralf Schäfer]], [[Mark Uniacke]], [[Ben-Hur Carlos Vieira Langoni Junior|Ben-Hur Carlos Vieira Langoni Júnior]], and [[Harvey Williamson]] signed an open letter to the [[CSVN]] and its board - to protest against their decision to ignore the [[ICGA]] suggestion and to allow Rybka playing their tournaments, the [[Dutch Open Computer Chess Championship]] and the [[International CSVN Tournament]], and declared they will no longer enter these tournaments under the current CSVN direction <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40489 Fwd: Open letter to the CSVN] by [[Marcel van Kervinck]], [[CCC]], September 21, 2011, on behalf of the signees</ref>.
==Different Views==
In November 2011, [[Ed Schroder|Ed Schröder]] announced his new web-sites <ref>[http://www.top-5000.nl/Rybka.htm Rybka vs ICGA a different view] by [[Ed Schroder|Ed Schröder]], November 09, 2011</ref> <ref>[http://www.top-5000.nl/evidence.htm Rybka evidence] by [[Ed Schroder|Ed Schröder]], November 09, 2011</ref> summarizing his alternative view of the historic ICGA - RYBKA event that led to the ban of [[Rybka]] and [[Vasik Rajlich]]. Short later, in January 2012, [[ChessBase]], a Rybka distributer, took a stand, publishing an article series in four parts by Danish mathematician and [[Computer Chess Forums|Rybka Forum]] moderator [[Søren Riis]] on their site - ''[[Søren Riis#Miscarriage|A Gross Miscarriage of Justice in Computer Chess]]'', also published as pdf <ref>[[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]</ref>.
<span id="Litmustest"></span>
==Litmus Test?==
Among other things matter of counter critic on Riis' article <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1763&p=15497#p15459 Re: Hyatt Is Gone!] by [[Mark Watkins|BB+]] [[Computer Chess Forums|OpenChess Forum]], Jan 03, 2012</ref>, the nasty <span style="background-color: #e5e5e5;">>= 0.0</span> match from Rybka's integer based - with Fruit's [[Float|float]] based time control code was declared a [https://en.wikipedia.org/wiki/Litmus litmus test] of the whole topic <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7811 A Gross Miscarriage of Justice in Computer Chess (part three)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 04, 2012 » Dots amazing: the case of the errant ‘0.0’</ref>. It was argued it could be a simple typo with only one additional trailing dot behind the zero. ‘0.’ already quantifies as float constant in [[C]] to force some compiler to emit the suspicious x87 instructions. Considering on how many places a chess program branches on the sign of an integer with <span style="background-color: #e5e5e5;">>= 0</span> or <span style="background-color: #e5e5e5;">< 0</span>, it is peculiar that the typo happened exactly there, in that time control code where Fruit has ‘0.0’. However, [[Miguel A. Ballicora]] found the initial float condition was different in Rybka, not <span style="background-color: #e5e5e5;">>= 0.0</span> but <span style="background-color: #e5e5e5;">> 0.0</span>, as published and mentioned by [[Ed Schroder|Ed Schröder]] in February 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=449909&t=42248 Re: Rybka 1.0 source code] by [[Ed Schroder|Ed Schröder]], [[CCC]], February 12, 2012</ref> <ref>[http://www.top-5000.nl/fadden.htm Did Vasik really copied Fruit's time control ?]</ref>. The different <span style="background-color: #e5e5e5;">> 0.0</span> condition was missed by the ICGA investigation panel, and implies the one and only possible literal copied line of Fruit code was at least modified.
<span id="Rebuttal"></span>
==Rebuttal==
At January 08, 2012 the [[ICGA]] responds with two rebuttal articles on [[Søren Riis|Riis']] ''[[Søren Riis#Miscarriage|A Gross Miscarriage of Justice in Computer Chess]]'', with an introduction letter from [[David Levy]], President of the ICGA <ref>[http://www.talkchess.com/forum/viewtopic.php?t=41866 ICGA response to ChessBase 4-part article] by [[Robert Hyatt]], [[CCC]], January 08, 2012</ref> <ref>[http://www.chessvibes.com/?q=reports/controversy-over-rybkas-disqualification-and-ban-update Controversy over Rybka's disqualification and ban (UPDATE) | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], January 08, 2012</ref> <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7836 Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012</ref>:
{| class="wikitable"
|-
| This week Dr Soren Riis posted a four part article on Chessbase.com in a somewhat belated attempt to defend [[Vasik Rajlich]]. Regular readers will recall that Rajlich's actions led the International Computer Games Association (ICGA) to find him guilty of breaking a crucial tournament rule, as a result of which the chess program Rybka was stripped of its World
Computer Chess Champion titles and Rajlich was banned for life from ICGA events.
Dr Riis gave his article a title to suggest that a miscarriage of justice has taken place. The ICGA now responds with two rebuttal articles, one by myself <ref>[[David Levy]] ('''2012'''). ''No Miscarriage of Justice - Just Biased Reporting''. [http://www.harveywilliamson.com/ICGA/DL_Rebuttal_to_Riis_article.January7th2012.doc doc]</ref> (as President of the ICGA) concerning some of the legalistic points raised by Riis's article, and a robust detailed and thorough technical rebuttal by [[Mark Watkins]] <ref>[[Mark Watkins]] ('''2012'''). ''A Critical Aanalysis of the four parts of Riis''. [http://harveywilliamson.com/ICGA/Riis3.pdf pdf]</ref>.
Everyone interested in the Rybka scandal should read both of these rebuttals and then decide for themselves who and what they believe - Dr Riis or the ICGA's investigation report.
Dr David Levy
President - ICGA
|}
<span id="FIDE"></span>
==FIDE==
In early 2012, the [[FIDE]] Ethics Commission <ref>[http://www.chessbase.com/newsdetail.asp?newsid=3844 Roberto Rivello: How the FIDE Ethics Commission works], [[ChessBase|ChessBase News]], May 11, 2007</ref> received a complaint signed by [[Vasik Rajlich]], co-signed by [[Søren Riis]], [[Chris Whittington]] and [[Ed Schroder|Ed Schröder]], against the [[ICGA]]. As announced at July 01, 2012, additional information is requested and the FIDE <ref>[http://www.fide.com/images/stories/NEWS_2012/FIDE/FIDE_Ethics_Commission_Decisions.pdf FIDE Ethics Commission ... during the meeting held in Lausanne on 30th June – 1st July 2012, assumed the following ... case 2/2012] (pdf)</ref>. Secretariat will communicate the decision to the complainants. The decision was made in April 2014. Parties are not allowed to publish the judgement as a whole, but may quote from it <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30056 Initiative in Stockfish vs. Crafty] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], April 07, 2015
[[Robert Hyatt|Bob]], 2015-04-20: [[FIDE]] has said this ...
[[Chris Whittington|Trotsky]], 2015-04-20: Strange. Do we have the same copy of the FIDE EC decision?</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30118 Complaint to FIFE Ethics Commission] by [[Lukas Cimiotti]], [[Computer Chess Forums|Rybka Forum]], April 24, 2015</ref>.
=See also=
* [[Open letter to the ICGA about the Rybka-Fruit issue]]
* [[Pre-Fruit Rybka and Crafty]]
* [[Quantifying Evaluation Features]]
=Publications=
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=272 pdf, February 12, 2011 Version] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1104 Feb 12 version: Rybka 1.0 Beta / Fruit 2.1 document] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 12, 2011</ref>
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=304 pdf, February 24, 2011 Version]
* [[Mark Watkins]] ('''2011'''). ''A comparison of Rybka 1.0 Beta and Fruit 2.1'', [http://www.open-chess.org/download/file.php?id=332 pdf, March 11, 2011 Version]
* [[Anthony Cozzie]] ('''2011'''). ''The Future of Computer Chess''. [[Selective Search]] 154, pp. 11, [http://www.chesscomputeruk.com/SS_154.pdf pdf] hosted by [[Mike Watters]]
* [[Jaap van den Herik]], [[Krzysztof Siewicz]] ('''2011'''). ''Open Source has a Price''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[David Levy]] ('''2011'''). ''Rybka Disqualified and Banned from World Computer Chess Championships''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[David Levy]] ('''2011'''). ''A Very Sad Case''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
* [[Mark Lefler]], [[Robert Hyatt]], [[Harvey Williamson]], [[Who's Who|ICGA panel]] ('''2011'''). ''Rybka Investigations and Survey of Findings for the ICGA''. [[ICGA Journal#34_2|ICGA Journal, Vol. 34, No. 2]]
: [[file:RybkaInvestigation.pdf]]
* [[Eric Hallsworth]] ('''2011'''). ''Rybka disqualified and banned by ICGA from World Computer Chess Championships, Lifetime Ban for Vasik Rajlich''. [[Selective Search]] 155, pp. 8, [http://www.chesscomputeruk.com/SS_155.pdf pdf] hosted by [[Mike Watters]]
* [[Mark Watkins]] ('''2011'''). ''Review of the Rybka case''. [http://www.open-chess.org/download/file.php?id=489 pdf] from [[Computer Chess Forums|OpenChess Forum]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1772 Rybka evidence recapitulation] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 03, 2012</ref>
* [[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]
* [[David Levy]] ('''2012'''). ''No Miscarriage of Justice - Just Biased Reporting''. [http://www.harveywilliamson.com/ICGA/DL_Rebuttal_to_Riis_article.January7th2012.doc doc]
* [[Mark Watkins]] ('''2012'''). ''A Critical Aanalysis of the four parts of Riis''. [http://harveywilliamson.com/ICGA/Riis3.pdf pdf]
* [[Ed Schroder|Ed Schröder]] ('''2012'''). ''Rybka reloaded''. [http://www.top-5000.nl/Rybka%20Reloaded.pdf pdf]
* [[Mark Watkins]] ('''2013'''). ''Review of the Rybka case''. [http://magma.maths.usyd.edu.au/~watkins/papers/RybkaRecap.pdf pdf]
* [[Jaap van den Herik]], [[Aske Plaat]], [[David Levy]], [[Daniel Dimov]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952114000093 Plagiarism in Game Programming Competitions]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3, [http://askeplaat.files.wordpress.com/2013/01/the-application-of-the-icga-rules-v15.pdf pdf preprint]
* [[Søren Riis]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952114000159 What makes a chess program original? Revisiting the Rybka case]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3
* [[Don Dailey]], [[Adam Hair]], [[Mark Watkins]] ('''2014'''). ''[http://www.sciencedirect.com/science/article/pii/S1875952113000177 Move Similarity Analysis in Chess Programs]''. [http://www.journals.elsevier.com/entertainment-computing/ Entertainment Computing], Vol. 5, No. 3, [http://magma.maths.usyd.edu.au/~watkins/papers/DHW.pdf preprint as pdf] <ref>[http://www.top-5000.nl/clone.htm A Pairwise Comparison of Chess Engine Move Selections] by [[Adam Hair]], hosted by [[Ed Schroder|Ed Schröder]]</ref>
* [[David Levy]] ('''2014'''). ''The RYBKA Case – Progress and Verdict''. [[ICGA Journal#37_4|ICGA Journal, Vol. 37, No. 4]]
* [[Ed Schroder|Ed Schröder]] ('''2015'''). ''The myth Rajlich copied Fruit''. [http://www.top-5000.nl/The-myth-Rajlich-copied-Fruit.pdf pdf]
=Forum Posts=
<ref>some [[Computer Chess Forums|Rybka Forum]] posts seem to require registration</ref>
==2011==
* [http://www.open-chess.org/viewtopic.php?f=5&t=1004 Node counting] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 20, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=37762 Fabien's open letter to the community] by [[Tord Romstad]], [[CCC]], January 23, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1014 Fabien's open letter to the community] by [[Tord Romstad]], [[Computer Chess Forums|OpenChess Forum]], January 23, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1023 Revisiting Strelka/Rybka] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 25, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1104 Feb 12 version: Rybka 1.0 Beta / Fruit 2.1 document] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 12, 2011
* [http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011
* [http://www.chessvibes.com/?q=reports/programmers-write-open-letter-about-rybka-fruit-issue Programmers write open letter about Rybka-Fruit issue : ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], March 01, 2011
* [http://www.hiarcs.net/forums/viewtopic.php?t=4038 Open letter to the ICGA about the Rybka-Fruit issue] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], March 01, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1175 Programmers Open Letter to ICGA on Rybka/Fruit] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 01, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=21216 Rybka 1.6.1] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], March 13, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=38440 Longer Article] by [[Anthony Cozzie]], [[CCC]], March 17, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1281 History of eval changes in Rybka versions] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], March 23, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39520 Rybka disqualified and banned from World Computer Chess Cham] by Tim Chan, [[CCC]], June 29, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22232 Rybka disqualified and banned from World Computer Chess Cham] by TheHug, [[Computer Chess Forums|Rybka Forum]], June 29, 2011
* [http://hiarcs.net/forums/viewtopic.php?t=4264&sid=ec7a3d377b4ca501b364599914913668 Rybka disqualified and banned from WCCC] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], June 29, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1463 Rybka disqualified and banned from WCCC] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], June 29, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39531 Rybka ban thoughts] by [[Dann Corbit]], [[CCC]], June 29, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39544 My two cents on Rybka's disqualification] by [[Joona Kiiski]], [[CCC]], June 30, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39546 Dismissed with prejudice] by [[Dann Corbit]], [[CCC]], July 01, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39545 Voir Dire] by [[Dann Corbit]], [[CCC]], July 01, 2011 <ref>[https://en.wikipedia.org/wiki/Voir_dire Voir dire from Wikipedia]</ref>
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22265 Vas say something] by siam, [[Computer Chess Forums|Rybka Forum]], July 01, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1471 Progess (often) is ugly, a summary try] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|OpenChess Forum]], July 03, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39593 Is Rybka that needs ICGA or the opposite ?] by [[Marco Costalba]], [[CCC]], July 03, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1475 The Evidence against Rybka] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], July 04, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22337 Why did the ICGA ignore this advice?] by [[John Sidles]], [[Computer Chess Forums|Rybka Forum]], July 06, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22370 Minority Report Plagiarism - Quantifying Evaluation Features] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 09, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22402 Vasik Rajlich responds to his accusers] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], July 12, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22421 In retrospect] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 14, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1552 Fruit 1.0 PST] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 13, 2011
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22679 Apology to Vas] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 17, 2011
* [http://www.open-chess.org/viewtopic.php?f=5&t=1570 PST of Fruit 2.1 and Rybka 1.0 Beta] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40854 Interesting reflection on a past statement] by [[Graham Banks]], [[CCC]], October 22, 2011
==2012==
* [http://www.open-chess.org/viewtopic.php?f=3&t=1771 ChessBase: A Gross Miscarriage of Justice in Computer Chess] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], January 02, 2012
* [http://www.open-chess.org/viewtopic.php?f=3&t=1771#p15455 Re: ChessBase: A Gross Miscarriage of Justice in Computer Chess] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 02, 2012
* [http://www.open-chess.org/viewtopic.php?f=3&t=1763&p=15497#p15459 Re: Hyatt Is Gone!] by [[Mark Watkins|BB+]] [[Computer Chess Forums|OpenChess Forum]], Jan 03, 2012
* [http://www.open-chess.org/viewtopic.php?f=5&t=1772 Rybka evidence recapitulation] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 03, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=41866 ICGA response to ChessBase 4-part article] by [[Robert Hyatt]], [[CCC]], January 08, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=23957 A Big Thanks and a Small Update] by [[Vasik Rajlich]], [[Computer Chess Forums|Rybka Forum]], January 08, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=23966 Re: Another question for Vas] by [[Vasik Rajlich]], [[Computer Chess Forums|Rybka Forum]], January 09, 2012
* [http://www.open-chess.org/viewtopic.php?f=5&t=1795 Fruit/Rybka timeline] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], January 09, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=41913 Rybka Investigation : Survey Of Evidence] by [[Adam Hair]], [[CCC]], January 10, 2012 <ref>[http://www.top-5000.nl/adamhair.htm The Rybka Investigation: A Survey Of Evidence From Both Perspectives] by [[Adam Hair]], January 2012, hosted by [[Ed Schroder|Ed Schröder]]</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=41968 CB: Feedback on the ICGA/Rybka disqualification scandal] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 Ted Summers], [[CCC]], January 13, 2012 <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7836 Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012</ref>
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=24065 Wiki-leaks] by [[Ed Schroder|Ed Schröder]], [[Computer Chess Forums|Rybka Forum]], January, 18, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=42078 "Fissure opens in chess AI scene" (Rob Beschizza/B] by [[Julien Marcel]], [[CCC]], January 20, 2012 <ref>[http://boingboing.net/2012/01/19/fissure-opens-in-chess-ai-scen.html Fissure opens in chess AI scene - Boing Boing] by [http://beschizza.com/ Rob Beschizza], January 19, 2012</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=42248 Rybka 1.0 source code] by [[Ed Schroder|Ed Schröder]], [[CCC]], January 31, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=24200 Andrew Dalke - copyright specialist] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], February 02, 2012 <ref>[http://www.dalkescientific.com/writings/diary/archive/ Andrew Dalke's Dairy archive]</ref>
* [http://www.open-chess.org/viewtopic.php?f=5&t=1869 On Dalke] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], February 19, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=25525 Rybka & ICGA at the FIDE Ethics Commission] by vesuvio, [[Computer Chess Forums|Rybka Forum]], August 17, 2012
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=25573 In Retrospect: What have we learned from ICCA vs Rybka?] by Bob Durrett, [[Computer Chess Forums|Rybka Forum]], August 25, 2012
==2013==
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27334 Copying vs. stealing, ideas vs. source code etc.] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], July 07, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27345 Bob: Harvey did most of the writing] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], July 22, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27356 Vas: could we have the final hearings in October or November], [[Computer Chess Forums|Rybka Forum]], July 26, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27350 Bob used as a tool to do the dirty job] by [[Jeroen Noomen|Jeroen]], [[Computer Chess Forums|Rybka Forum]], July 24, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27363 Open thread: a collection of Hyatt lies in the Rybka case] by [[Jeroen Noomen|Jeroen]], [[Computer Chess Forums|Rybka Forum]], July 27, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27389 Was pre-beta Rybka ever "released"?], [[Computer Chess Forums|Rybka Forum]], July 29, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27386 The jury, the judge and the prosecutor], [[Computer Chess Forums|Rybka Forum]], August 01, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27421 Engine crash / incorrect mate score ], [[Computer Chess Forums|Rybka Forum]], August 08, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27412 adult discussions ;-) ], [[Computer Chess Forums|Rybka Forum]], August 09, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27380 More Bob lies] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 31, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27416 R.V. about Rybka 1.0 beta vs Fruit 2.1] by [[Richard Vida]], [[Computer Chess Forums|Rybka Forum]], August 11, 2013
: [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27472 Asides and commentary on RV's decompilation and reports] by turbojuice1122, [[Computer Chess Forums|Rybka Forum]], August 20, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27490 Bob's suggested punishment] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 21, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27491 Complaining about formulas or ideas] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 21, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27489 The originality claim...] by [[Dann Corbit|user923005]], [[Computer Chess Forums|Rybka Forum]], August 23, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27509 Vas quotes and misquotes discussions] by [[Robert Hyatt]], [[Computer Chess Forums|Rybka Forum]], August 26, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27518 The ICGA tribunal, what went wrong] by [[Dann Corbit|user923005]], [[Computer Chess Forums|Rybka Forum]], August 28, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27539 Rule 2 interpretation] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 28, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27520 What does "copy" mean?] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], August 29, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27523 The obfuscation story] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], August 29, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27537 Crafty/Fruit projection] by Nick, [[Computer Chess Forums|Rybka Forum]], August 30, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27550 Occam's razor vs Hyatt's razor] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 01, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27637 Rook eval Rybka vs Fruit] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 16, 2013
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27725 ChessVibes article] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], October 01, 2013
==2015==
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30056 Initiative in Stockfish vs. Crafty] by [[Chris Whittington|Trotsky]], [[Computer Chess Forums|Rybka Forum]], April 07, 2015
: [[Robert Hyatt|Bob]], 2015-04-20: [[FIDE]] has said this ...
: [[Chris Whittington|Trotsky]], 2015-04-20: Strange. Do we have the same copy of the FIDE EC decision?
* [http://www.open-chess.org/viewtopic.php?f=3&t=2808 FIDE Rules on ICGA - Rybka controversy] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], April 14, 2015
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30118 Complaint to FIFE Ethics Commission] by [[Lukas Cimiotti]], [[Computer Chess Forums|Rybka Forum]], April 24, 2015
* [http://www.talkchess.com/forum/viewtopic.php?t=56112 FIDE Ethics Commission ruling on ICGA/Rybka complaint] by [[Graham Banks]], [[CCC]], April 24, 2015
* [http://www.open-chess.org/viewtopic.php?f=3&t=2810 FIDE Ethics Commission dealings (Case 2/12)] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 24, 2015
=External Links=
* [http://www.chessvibes.com/?q=reports/attack-of-the-clones Attack of the clones : ChessVibes] by [[David Levy]], 19 February, 2011
* [http://www.spiegel.de/netzwelt/gadgets/schach-software-rybka-programmierer-vermuten-intelligenzklau-a-748616.html Schach-Software Rybka - Programmierer vermuten Intelligenzklau] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], March 03, 2011 (German)
* [https://www.heise.de/newsticker/meldung/Plagiatsvorwurf-gegen-Computerschach-Weltmeister-1200222.html Plagiatsvorwurf gegen Computerschach-Weltmeister], [http://de.wikipedia.org/wiki/Heise_online Heise online], March 01, 2011 (German)
* [http://www.chessvibes.com/?q=reports/rybka-disqualified-and-banned-from-world-computer-chess-championships Rybka disqualified and banned from World Computer Chess Championships | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], June 29, 2011
* [http://chess.business-news-blog.eu/2011/rybka-banned-by-international-games-federation-rybka-ruling/ Rybka banned by International Games Federation – Rybka Ruling]
* [http://www.extremetech.com/extreme/88610-rybka-the-worlds-best-chess-engine-outlawed-and-disqualified Rybka, the world’s best chess engine, outlawed and disqualified | ExtremeTech] by [http://www.mrseb.co.uk/ Sebastian Anthony] on June 29, 2011
* [https://m.washingtontimes.com/news/2011/jun/30/computer-chess-champ-stripped-of-its-four-titles/ Computer chess champ stripped of its four titles] by [http://www.linkedin.com/pub/claire-courchane/2a/857/3b Claire Courchane], [https://en.wikipedia.org/wiki/The_Washington_Times Washington Times], June 30, 2011
* [https://www.itproportal.com/2011/06/30/rybka-disqualified-banned-on-plagiarism-charges/ Rybka Disqualified, Banned On Plagiarism Charges | ITProPortal.com] by [http://www.itproportal.com/staff/ravimandalia/ Ravi Mandalia], June 30, 2011
* [http://boylston-chess-club.blogspot.com/2011/06/rybka-banned-from-computer-champs.html Boylston Chess Club Weblog: Rybka banned from computer champs; stripped of all its titles], June 30, 2011
* [https://metro.co.uk/2011/06/30/computer-chess-reels-from-biggest-sporting-scandal-since-ben-johnson-62543/ Computer chess reels from 'biggest sporting scandal since Ben Johnson' | Metro.co.uk] by [http://tariqtahir.com/ Tariq Tahir], June 30th, 2011
* [https://www.heise.de/newsticker/meldung/Schachcomputer-Weltmeister-nachtraeglich-disqualifiziert-1271033.html Schachcomputer-Weltmeister nachträglich disqualifiziert], [http://de.wikipedia.org/wiki/Heise_online Heise online], June 30, 2011 (German)
* [http://www.spiegel.de/netzwelt/games/plagiats-skandal-weltmeisterprogramm-rybka-verliert-alle-titel-a-771620.html Weltmeisterprogramm Rybka verliert alle Titel] by [http://www.spiegel.de/extra/0,1518,632080,00.html Frank Patalong], [https://en.wikipedia.org/wiki/Der_Spiegel#Spiegel_Online Spiegel Online], July 01, 2011 (German)
* [https://www.nytimes.com/2011/07/03/crosswords/chess/developer-of-computer-chess-champ-accused-of-stealing-code.html?_r=1 Developer of Computer Chess Champ Accused of Stealing Code] by [https://topics.nytimes.com/top/reference/timestopics/people/m/dylan_loeb_mcclain/index.html?inline=nyt-per Dylan Loeb McClain], [https://en.wikipedia.org/wiki/The_New_York_Times NYTimes.com], July 02, 2011
* "Another Conversation with Vasik Rajlich" By [[Nelson Hernandez]] (on Rybka chess), July 04, 2011, [https://en.wikipedia.org/wiki/YouTube YouTube] Video <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=22402 Vasik Rajlich responds to his accusers] by [[Nelson Hernandez]], [[Computer Chess Forums|Rybka Forum]], July 12, 2011</ref>
: {{#evu:https://www.youtube.com/watch?v=cQshTNJ4pSM|alignment=left|valignment=top}}
* [https://diepresse.com/home/spectrum/spielundmehr/676421/Geklontes-Fischchen Geklontes Fischchen] by [[Stefan Löffler]], July 08, 2011, [http://diepresse.com/home/index.do DiePresse.com] (German)
* [http://www.top-5000.nl/Rybka.htm Rybka vs ICGA a different view] by [[Ed Schroder|Ed Schröder]], November 09, 2011
* [http://www.top-5000.nl/evidence.htm Rybka evidence] by [[Ed Schroder|Ed Schröder]], November 09, 2011
* [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-one A Gross Miscarriage of Justice in Computer Chess (part one)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 02, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-two A Gross Miscarriage of Justice in Computer Chess (part two)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 03, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-three A Gross Miscarriage of Justice in Computer Chess (part three)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 04, 2012
: [https://en.chessbase.com/post/a-gro-miscarriage-of-justice-in-computer-che-part-four A Gross Miscarriage of Justice in Computer Chess (part four)] by [[Søren Riis]], [[ChessBase|ChessBase News]], January 05, 2012 <ref>[[Søren Riis]] ('''2012'''). ''A Gross Miscarriage of Justice in Computer Chess''. [http://www.chessbase.com/news/2011/riis01.pdf pdf] hosted by [[ChessBase]]</ref>
* [http://www.chessvibes.com/?q=reports/controversy-over-rybkas-disqualification-and-ban-update Controversy over Rybka's disqualification and ban (UPDATE) | ChessVibes] by [http://www.chessvibes.com/?q=peterdoggers Peter Doggers], January 08, 2012
* [http://www.top-5000.nl/adamhair.htm The Rybka Investigation: A Survey Of Evidence From Both Perspectives] by [[Adam Hair]], January 2012, hosted by [[Ed Schroder|Ed Schröder]]
* [https://en.chessbase.com/post/feedback-on-the-icga-rybka-disqualification-scandal Feedback on the ICGA/Rybka disqualification scandal], [[ChessBase|ChessBase News]], January 13, 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=41968 CB: Feedback on the ICGA/Rybka disqualification scandal] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 Ted Summers], [[CCC]], January 13, 2012</ref>
* [https://boingboing.net/2012/01/19/fissure-opens-in-chess-ai-scen.html Fissure opens in chess AI scene - Boing Boing] by [http://beschizza.com/ Rob Beschizza], January 19, 2012 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=42078 "Fissure opens in chess AI scene" (Rob Beschizza/B] by [[Julien Marcel]], [[CCC]], January 20, 2012</ref>
* [https://en.chessbase.com/post/icga-rybka-controversy-an-interview-with-david-levy-1 ICGA/Rybka controversy: An interview with David Levy (1)], [[ChessBase|ChessBase News]], February 06, 2012
: [https://en.chessbase.com/post/icga-rybka-controversy-an-interview-with-david-levy-2 ICGA/Rybka controversy: An interview with David Levy (2)], [[ChessBase|ChessBase News]], February 10, 2012
* [https://en.chessbase.com/post/icga-rybka-controversy-feedback ICGA/Rybka controversy: Feedback], [[ChessBase|ChessBase News]], February 17, 2012
* [http://www.chessvibes.com/?q=rybka-case-greatest-injustice-perpetrated-in-computer-chess-history-part-1 Rybka case "greatest injustice perpetrated in computer chess history" (Part 1) | ChessVibes] by [[Ed Schroder|Ed Schröder]], October 01, 2013
: [http://www.chessvibes.com/?q=rybka-case-greatest-injustice-perpetrated-in-computer-chess-history-part-2 Rybka case "greatest injustice perpetrated in computer chess history" (Part 2) | ChessVibes] by [[Ed Schroder|Ed Schröder]], October 05, 2013
=References=
<references />
'''[[ICGA Investigations|Up one level]]'''
