Fabien's open letter to the community

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diep
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Re: Fabien's open letter to the community

Post by diep » Sat Jan 29, 2011 3:40 pm

Tord Romstad wrote:My good friend Fabien Letouzey, author of Fruit, asked me to post the following message for him:
Hello,

Long time no see.

First, I am not back to computer chess, sorry about that. I just want to clarify a few things. Sorry if that's old but there is some misunderstanding I need to fix, and I found out only yesterday. Bear in mind that I am mostly unaware of what has happened for five years though.

First there was the Strelka case. Dann approached me with some "Strelka" source code for me to check. I had never heard of it. I assumed it was some closed-source free engine and that people wanted to know whether it was based on the Fruit source code.

The short answer was "no", it was not a verbatim copy of the source code. All the code had been typed (can't say "designed" though, see below) by an individual. So legally there was no issue that I knew of. It was however a whole re-write (copy with different words if you like, similar to a translation) of the algorithms. Not just an extraction of a couple of ideas as is common, and normal.

That being said, some original changes and ideas were also included in the program. So it was, as has since been stated many times in fora I suppose, a bitboard re-write of Fruit with some personal (or otherwise) ideas. Also note that the source code Dann sent me might not be the from the 2.0 version.

Edit: I've just had a look at the 2.0 sources. On top of what I said above, there are many constant and function names that are identical to Fruit's. I remember noticing it back then as well.

Hope it helps, because my email answer to Dann was unusually short and cryptic even by my standards. And Dann, please next time make it clear when you want a public statement instead of a private opinion, thanks.

I want to point out something immediately: there was no mention of Rybka whatsoever. Indeed I was unaware of any relation between Strelka and Rybka, this is precisely what I learned only yesterday. I insist because it seems I have often been quoted about "not caring" about the (possible) Fruit/Rybka relationship, but this is not so. Strelka did not look like a problem because I assumed it was free.

Next, I was approached by Ryan (I think) and Christophe Theron about whether I could help with some "possible Fruit code inside Rybka" issues. I answered "yes, but how?", but did not get a reply. This did not make me really aware of a clone possibility however because I thought they were talking about some insignificant UCI-handling code or whatnot. Also this was several years after the initial Rybka release, and I guess quite a few people had a close look at it. Apparently Chrilly did?

Now if someone could tell me a bit more about the major events last five years and the current state of affairs, I'd be much obliged.

A few things I noticed yesterday, can you confirm?
- Rybka search info was obfuscated in some way (like displaying depth-3 or something), any pointers on details please?
- Vasik claimed that Strelka 2.0 is a clone of Rybka 1.0 (and you know what that would imply!)
- Zach Wegner found many Fruit ideas (and nearly identical code) in Rybka 1.0; I think someone else did, too
- Some even stronger open-source program appeared as a decompilation of Rybka (with own ideas, sounds familiar), what came up of looking at those?

Any questions, now is the one time to ask.

Thanks for your attention,

Fabien Letouzey.
Let me handle your topics 1 by 1.

Seems Rybka took shape based upon some remarks i made.

My remarks on automatic tuning: "It would be possible to automatic tune the material evaluation" (statement done end 2004, januari 2005)

Remark 2: "So far no one managed to automatic tune chess engines very well that have more than a few parameters". (statement done end 2004)

At that time i was unaware of the army helping out the Brutus project, later on called Hydra project, with automatic tuning. Note knowing Chrilly just has a few parameters according to insiders.

Remark on material evaluation: "It is possible to quickly hash it"

Remark on commercially representing a program to the outsid world: "Titled chessplayers seem to sell chess software a lot better than non titled chessplayers". (Q1 2005)

Finding someone from who always says 'see ya' for selling rybka of course was a direct consequence of my above remark.

I did do more remarks:

Remark on obfuscation: "For many years the secret of Frans Morsch and Richard Lang was the amount of nps it got." (Q1 2005)

"In fact it seems even a good idea to hide the super selective search depth that's behind the mainsearch". (Q1 2005)

At an experimental Diep version where i forward pruned a lot last 3 plies, i reduced search depth with 3. (Q4 2004 / Q1 2005)

My explanation then was: "If you search that deep you don't want to give away that info of course". (end 2004/ start 2005)

Then came a kiler Fruitversion end Q1 2005.

The next remarks all are from around the world champs, during it or short after it:

The generic question i dropped was this: "How strong would Fruit be if you fix some obvious holes of it".

And i listed the next holes:

a) it is crappy programmed C++ code, quick & dirty, you can speedup this code quicktime getting more nps

b) it's not parallel

c) its search is very inefficient and history pruning prunes too little;
with such simplistic evaluation function that's so dependant upon static piece square tables you can prune way more, especially last few plies.

d) biggest gap, so i said, were 3 huge weaknesses in its evaluation function, all of which have been fixed in rybka 1.0 already:
a) Fruit knows too little about material evaluation; it takes too many times the wrong material
b) it doesn't know about stopped passed pawns a lot, it gives too big bonuses for stopped/blocked passed pawns at 6th and especially 7th row;
in many testgames here it lost because of taking a passer at 7th row + 2 other pawns, against a piece and lost then.
c) its kingsafety is too limited and vulnerable to surprise attacks

e) I noticed also that much of Fruit's succes, despite such tiny evaluation function being so passive tuned, was because it searched that 17 ply. Other beancounters from the past which were passive tuned usually got completely hammered at the kingsafety. With Fruit this occured a lot less, as it seems majority of kingside evaluation is short term knowledge; if you search your way out there, most of the bonuses/penalties there are just patzerknowledge that can distract your search a lot.

For example who doesn't remember how Fritz easily sacraficed 1 or 2 pawns just to get half open files against the opponent king, as it simply gave half open file against opponent king 0.5 pawn bonus. Fritz lost many games that manner against lesser gods at the time.

Even then of course, objectively seen Fruit lacks knowledge there.

I also made a huge mistake when observing next. First the correct observation:

f) Fruit seems to make a lot of points because it only has knowledge in its evaluation function that works, it has basically no bugs there.

This bugfreeness was however a result of huge automatic testing carried out by Fabien. A primitive form of automatic tuning i'd call it.

Q1 2005 several automatic tuning project got announced towards me.

Not knowing the huge obfuscation games that got played out there, end 2005 several persons again started lying to me, claiming those projects all failed, whereas Zappa had won the world title.

Silly me.

It took until 2007 the release of the strelka code, for me to realize, that the whole project was one giant NSA project about automatic tuning.

At least $100 milllion must have been put into it.

As for the software engineering, they just grabbed the above remarks i made. It's possibe just 1 programmer carried out the project and then they found someone from the see ya dudes with a chess title to walk around abroad.

Now the big question is of course, why use secret software to tune. In this nation all that is forbidden as far as i know. It is not legal here to use software from a classified project to tune and test a program that is out there available to freely copy or buy.

All this just to win from a few Einsteins, so just to avoid them looking brilliant?

It is obvious some Russians didn't miss this and threw the code of it, under the name strelka, on the internet. Then everyone could learn the truth.

So by 2007 when some programmers started studying that source code, i got from several chessprogrammers the same comment, GCP being the first "Would all those parameters in Rybka be tuned by hand, they look SO SO bizarre".

Rybka is a classical form of NSA software engineering: do the minimum to get strong, and a maximum of usage of hardware at an unknown NSA location somewhere in the USA.

At that time, we simply didn't have the hardware in Netherlands to do tuning just like that.

So my big mistake was to initially guess just 1 guy had done the programming of rybka; whereas the programmers of course knew better, as already commented here in CCC by several programmers over the past years; it is possible to prove how many people have been involved in the different projects as shown by several authors, which proves clearly that dozens of guys were involved somehow, and they all got paid for many years.

Total project costs must've been at least a 100 million dollar.

It is amazing why at such a late stage they involved chessprogrammers into the project. Maybe because majority comes from Europe.

My conclusion is they wasted a lot of government funding just for a few mediocre guys, whose intelligence can't really handle the information they have, to play at the level of the Einsteins. Just for wanting to feel better than they are using sneaky methods. Very disgusting.

If you throw 100 million at a project in a science where everything is about testing, of course you always win.

Vincent

p.s. If a lot of people start lying towards you, in order to cover up something, you know secret services are involved; therefore proving it is a military project. All the cables in wikileaks are a joke and most of it is desinformation, compared to what happened here.

Robert Flesher
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Re: Fabien's open letter to the community

Post by Robert Flesher » Sat Jan 29, 2011 4:33 pm

Ant_Gugdin wrote:
Robert Flesher wrote:
Watchman wrote:
Graham Banks wrote:
bob wrote:.....the verdict is always "not guilty" as opposed to "innocent"............
I always thought that a court either convicted someone or cleared them of guilt.
Not under U.S. Law. As Dr. Hyatt has said, beyond a reasonable doubt is the standard of proof required for a conviction in a criminal (as opposed to a civil) case. It does not establish innocence… just that the “facts” and evidence of the case, presented by the prosecution, were not enough to lead a “reasonable person” to believe beyond any reasonable doubt that the accused had met or committed certain acts or elements that led to the violation of a criminal statute (hence a crime being committed).

Example from an Indiana Statute:
IC 35-43-4-2
Theft; receiving stolen property
Sec. 2. (a) A person who knowingly or intentionally exerts unauthorized control over property of another person, with intent to deprive the other person of any part of its value or use, commits theft, a Class D felony.

So you must (all terms defined by statute):
(a) knowingly or intentionally
(b) exert unauthorized control over property of another person
(c) with intent to deprive the other person of any part of its value or use

If a prosecutor cannot convince a reasonable person (twelve in this case) that a person committed each of those elements (beyond a reasonable doubt, not 100% doubt, just what is reasonable)… there is no conviction or establishment of guilt. Innocence is an entirely another matter.

The type of case we are talking is a civil case… again Dr. Hyatt has said this, one that uses a much lower standard of proof, that of “preponderance of the evidence.” Preponderance of the evidence is nothing more than a fancy way of saying: “more likely than not” or a greater that 50% chance. Put everything in the scales… if it tips slightly in one direction… that is “preponderance of the evidence.” It is the burden of proof I have argued before that should be applied in instances such as this (though with some of our programming experts, I dare say, they sound convinced to a higher standard, one exceeding “beyond a reasonable doubt” yet that is still not enough for many).

What I cannot understand is… why this community does not select individuals with certain programming qualifications who have researched this matter thoroughly to the point of giving an educated opinion… and then abiding by that decision. Would not that be preferable? The community “policing” itself? If there were 9 chess engine authors and you get a majority vote (and a brief, layman’s explanation why their opinion).

Graham I know you to be a reasonable man... would something like that, a "review board"... be acceptable to you? It's basically a rhetorical question and I certainly do not expect an answer (I am not attempting to “put you on the spot”). Something like that would be wise to consider for a time… and in this case with Fruit/Rybka it is essentially a loaded question.

I think that any case involving the issues presented here will most certainly fall under the same verdict ruling that civil law follows, that being the " balance of probabilities". These situations are almost always solved under tort law rules from my experience. Whereas "beyond a reasonable doubt" is the standard for the more serious criminal acts such as, crimes against a person ( assualt, robbery, theft, murder, etc, etc), or crimes against property. I am not sure how this works in other countries, but this is a brief explantion of how it works here in Canada. With tort law it will not be easy for Vas ( trust me I have vast experience here), as the balance of probabilities weight heavily against him.
If Rybka 1 had been sold for profit then we could make an educated guess that there would be a bad outcome for Vas, although it's a question of either Russian or French law. There appears to be extensive proof that Rybka 1 is a Fruit derivative.

However, you would expect (again, on an educated guess) that if some of Vas' money is to be taken from him, people are going to need to prove that Rybka 3 is a Fruit derivative as well. That would mean all the work which Robert Hyatt, Zach Wegner etc did examining Rybka 1 has to be done again with Rybka 3. And it will be more difficult this time, as the similarities between Rybka 3 and Fruit will be much more nebulous.

Maybe someone should get in touch with the Ippolit authors, to ask for some help. :)

Really, this should have been sorted five years ago by the FSF forcing Vas to release the Rybka 1 source code.

I am pretty sure it was, if memory serves me. I could check my credit card records, but I am pretty sure I purchased Rybka 1.2.

bob
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Re: Fabien's open letter to the community

Post by bob » Sat Jan 29, 2011 4:55 pm

Graham Banks wrote:
bob wrote:.....the verdict is always "not guilty" as opposed to "innocent"............
I always thought that a court either convicted someone or cleared them of guilt.
You can not prove someone did not do something. You can sometimes prove they did. The "not guilty" takes care of the case where you can't prove, within a reasonable doubt, that they did it. It is a subjective call. Is that eye witness lying? Is that person providing an alibi lying?

That's why there is a jury... He is either proven guilty, or not proven guilty. "innocent" is a different animal entirely and does not factor in.

SzG
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Re: Fabien's open letter to the community

Post by SzG » Sat Jan 29, 2011 4:55 pm

Robert Flesher wrote:
Ant_Gugdin wrote: If Rybka 1 had been sold for profit

I am pretty sure it was, if memory serves me. I could check my credit card records, but I am pretty sure I purchased Rybka 1.2.
No need to check. I purchased Rybka 1.2f as well.
Gabor Szots

CCRL testing group

bob
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Re: Fabien's open letter to the community

Post by bob » Sat Jan 29, 2011 4:56 pm

Albert Silver wrote:
Graham Banks wrote:
bob wrote:.....the verdict is always "not guilty" as opposed to "innocent"............
I always thought that a court either convicted someone or cleared them of guilt.
No, you are confused. There are lots of criminals who are not guilty, just as there are lots of innocents who are guilty.
I think you meant "lots of people found guilty but were really innocent, and lots of people found not guilty but really were guilty." An "innocent" can't possibly be "guilty".

bob
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Re: Fabien's open letter to the community

Post by bob » Sat Jan 29, 2011 4:58 pm

Robert Flesher wrote:
Watchman wrote:
Graham Banks wrote:
bob wrote:.....the verdict is always "not guilty" as opposed to "innocent"............
I always thought that a court either convicted someone or cleared them of guilt.
Not under U.S. Law. As Dr. Hyatt has said, beyond a reasonable doubt is the standard of proof required for a conviction in a criminal (as opposed to a civil) case. It does not establish innocence… just that the “facts” and evidence of the case, presented by the prosecution, were not enough to lead a “reasonable person” to believe beyond any reasonable doubt that the accused had met or committed certain acts or elements that led to the violation of a criminal statute (hence a crime being committed).

Example from an Indiana Statute:
IC 35-43-4-2
Theft; receiving stolen property
Sec. 2. (a) A person who knowingly or intentionally exerts unauthorized control over property of another person, with intent to deprive the other person of any part of its value or use, commits theft, a Class D felony.

So you must (all terms defined by statute):
(a) knowingly or intentionally
(b) exert unauthorized control over property of another person
(c) with intent to deprive the other person of any part of its value or use

If a prosecutor cannot convince a reasonable person (twelve in this case) that a person committed each of those elements (beyond a reasonable doubt, not 100% doubt, just what is reasonable)… there is no conviction or establishment of guilt. Innocence is an entirely another matter.

The type of case we are talking is a civil case… again Dr. Hyatt has said this, one that uses a much lower standard of proof, that of “preponderance of the evidence.” Preponderance of the evidence is nothing more than a fancy way of saying: “more likely than not” or a greater that 50% chance. Put everything in the scales… if it tips slightly in one direction… that is “preponderance of the evidence.” It is the burden of proof I have argued before that should be applied in instances such as this (though with some of our programming experts, I dare say, they sound convinced to a higher standard, one exceeding “beyond a reasonable doubt” yet that is still not enough for many).

What I cannot understand is… why this community does not select individuals with certain programming qualifications who have researched this matter thoroughly to the point of giving an educated opinion… and then abiding by that decision. Would not that be preferable? The community “policing” itself? If there were 9 chess engine authors and you get a majority vote (and a brief, layman’s explanation why their opinion).

Graham I know you to be a reasonable man... would something like that, a "review board"... be acceptable to you? It's basically a rhetorical question and I certainly do not expect an answer (I am not attempting to “put you on the spot”). Something like that would be wise to consider for a time… and in this case with Fruit/Rybka it is essentially a loaded question.

I think that any case involving the issues presented here will most certainly fall under the same verdict ruling that civil law follows, that being the " balance of probabilities". These situations are almost always solved under tort law rules from my experience. Whereas "beyond a reasonable doubt" is the standard for the more serious criminal acts such as, crimes against a person ( assualt, robbery, theft, murder, etc, etc), or crimes against property. I am not sure how this works in other countries, but this is a brief explantion of how it works here in Canada. With tort law it will not be easy for Vas ( trust me I have vast experience here), as the balance of probabilities weight heavily against him.
I think you mean "preponderance of the evidence" which is, simply, that there is more evidence supporting one side than the other, but only a simple majority, not the "reasonable doubt" standard for criminal proceedings.

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mhull
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Re: Fabien's open letter to the community

Post by mhull » Sat Jan 29, 2011 5:05 pm

Graham Banks wrote:
bob wrote:.....the verdict is always "not guilty" as opposed to "innocent"............
I always thought that a court either convicted someone or cleared them of guilt.
What do you care? An accusation is good enough for you, unless the accusation is against Rybka. Can you explain this discrepancy?
Matthew Hull

K I Hyams
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Re: Fabien's open letter to the community

Post by K I Hyams » Sat Jan 29, 2011 5:25 pm

SzG wrote:
Robert Flesher wrote:
Ant_Gugdin wrote: If Rybka 1 had been sold for profit

I am pretty sure it was, if memory serves me. I could check my credit card records, but I am pretty sure I purchased Rybka 1.2.
No need to check. I purchased Rybka 1.2f as well.
Quote from the notice that Rybka 2 was available.
"If you were a Rybka 1 customer, you can send me an email with your intention to pay and I will send you the version. Non-Rybka 1 customers may need to be a........"

Ant_Gugdin
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Re: Fabien's open letter to the community

Post by Ant_Gugdin » Sat Jan 29, 2011 5:25 pm

I've just been doing some more digging on this.

Vas lives in Poland. Polish legislation relating to copyright is published online at http://en.wikisource.org/wiki/Polish_Co ... ruary_1994 (query whether this is up to date).

This Act contains specific territorial provisions which apply to Fruit on the basis that Fabien is an EU citizen. It raises a number of interesting issues and it would take a very long post to cover them all.

In particular, however, I had been assuming that the possible outcomes here were limited to Vas being sued for damages or possibly being compelled to withdraw Rybka 4 from circulation (I had also thought that Chessbase should take legal advice on where they stand). Being ignorant of copyright law, I did not think there was any real possibility of Vas having committed a criminal offence.

It looks like I was wrong. From the Act:
Chapter 14. Criminal Liability

Article 115.
1. Whoever claims the authorship or misleads others as to the authorship of a whole or part of another person's work or performance, shall be liable to a fine, restriction of liberty or imprisonment up to 3 years.
2. The same penalty shall be imposed on anyone who disseminates, without indicating the name or the pseudonym of the author, someone else's work in the original or derivative version, or performance, or publicly distorts such work, performance, phonogram, videogram or broadcast.
3. Whoever, in order to gain material benefits in a manner other than specified in paragraph 1 or 2, infringes upon another person's copyright or related rights specified in Articles 16, 17, 18, 19 paragraph 1 or 2 , Article 20 paragraphs 1-4, Article 40 paragraph 1 or 2, Article 86, Article 94, paragraph 4, and Article 97, shall be liable to a fine, restriction of liberty or imprisonment up to1 year.


Article 116.
1. Whoever, without authorization or against its terms and conditions, disseminates someone else's work, in the original or derivative version, performance, phonogram, videogram or broadcast shall be liable to a fine, restriction of liberty or imprisonment for the period of up to 2 years.
2. If the perpetrator commits the act specified in paragraph 1 above in order to gain material benefits, he shall be liable to imprisonment for the period of up to 3 years.
3. If the perpetrator makes the offence specified in paragraph 1 above a regular source of income or organizes or manages a criminal activity, as specified in paragraph 1, he shall be liable to imprisonment from 6 months up to 5 years.
4. If the perpetrator of the act specified in paragraph 1 above acts unintentionally, he shall be liable to a fine, restriction of liberty or imprisonment for the period of up to one year.


Article 117.
1. Whoever, without authorization or against its conditions, fixes or reproduces another person's work in the original or derivative version, performance, phonogram, videogram or broadcast, for the purpose of its dissemination, shall be liable to a fine, restriction of liberty or imprisonment for the period of up to 2 years.
2. If the perpetrator makes the offence specified in paragraph 1 a regular source of income or organizes or manages a criminal activity, as specified in paragraph 1 above, he shall be liable to imprisonment for the period of up to 3 years.


Article 118.
1. Whoever, in order to gain material benefits, purchases or assists in selling or accepts or assists in concealing objects, which are carriers of a work, performance, phonogram or videogram being disseminated or reproduced without authorization or against its conditions, shall be liable to imprisonment for the period from 3 months to 5 years.
2. If the perpetrator makes the offence specified in paragraph 1 a regular source of income or organizes or manages criminal activity, as specified in paragraph 1, shall be liable imprisonment from 1 to 5 years.
3. Where on the basis of circumstances the perpetrator of the act specified in paragraph 1 or 2 should and could presume that the object has been obtained through an illegal act, he shall be liable to a fine, restriction of liberty or imprisonment for the period of up to 2 years.
The definition of "derivative" is unclear:
Article 2.
1. The work derived from another author's work (derivative work), in particular its translation, alteration or adaptation, shall be copyrighted without detriment to the original work.
2. The disposal and use of the derivative work shall depend on the permission of the author of the original work (derivative copyright) unless the author's economic rights to the original work have expired. In the case of a database which has the properties of a work the author shall give his permission to the adaptation of such database.
3. The author of the original work may withdraw his permission if the derivative work has not been disseminated within five years from granting such permission. The remuneration paid to the author shall not be refundable.
4. The work which has been created under the inspiration of another author's work shall not be deemed the derivative work.
5. Copies of the derivative work shall indicate the author and the title of the original work.
Vas did not comply with the GPL, so he did not have any permission/ authorisation.

bhandelman
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Re: Fabien's open letter to the community

Post by bhandelman » Sat Jan 29, 2011 5:33 pm

Ant_Gugdin wrote: What does this bit from the GPL mean?
b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License.
This part means you have to let others use your source code in GPL projects for free since it was derived from another GPL project. So Vas could sell Rybka, make the source available for free, and he has to let someone download that source code, make their own chess engine from it, and choose to either sell it or give it away, which no expectation Vas will receive any compensation other than the new modifications to the code. That is what the license part is referring to. An example would be how ICC now includes Stockfish in its Blitzin client. One of the install options is to also install the source code for Stockfish, so they cover the distribution portion of the license, and they haven't made any modifications, so they don't have to include anything special, and they don't have to pay a dime to the Stockfish team because they are distributing on their own. The only requirement is they do not take credit for Stockfish, they still have to acknowledge the proper author/copyright holder for it. Chess companies have been using Crafty in this way for probably a decade; I know Fritz 12 still comes with a version of Crafty, and most of the FICS clients include Crafty as well.
Ant_Gugdin wrote: - Even though Rybka 1 was a rip-off, the first commercial version, Rybka 3 (I think) is sufficiently different from Fruit that he can't be sued. This is a pretty fundamental point. As I understand it, people have spent ages and ages proving that Rybka 1 is dodgy but nobody has even begun to try with Rybka 3. Proving that Rybka 3 is sufficiently close to Fruit would involve a lot of time and effort.

Moreover, even if he does escape on a technicality, there is a question for Chessbase about whether they want to continue carrying his products in their store.
All they have to do is prove Rybka 1 was derived from GPL based code. There is no way Rybka 3 contains no code from Rybka 1, so it would be considered derived even if it no longer contained any Fruit code. This is where FSF lawyers and experts would have to get involved, because Vas claims all the code prior to Rybja 4 is gone.
Benjamin Handelman
ICC/FICS/Playchess - bhandelman

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