Stockfish: Our lawsuit against ChessBase

[DrCliche]

A pleasant and welcome surprise, to be sure.

[supersharp77]

In case you didn’t notice: https://stockfishchess.org/blog/2021/ou ... chessbase/

https://stockfishchess.org/blog/2021/ou ... chessbase/

"2021-07-20
Our lawsuit against ChessBase
The Stockfish project strongly believes in free and open-source software and data. Collaboration is what made this engine the strongest chess engine in the world. We license our software using the GNU General Public License, Version 3 (GPL) with the intent to guarantee all chess enthusiasts the freedom to use, share and change all versions of the program.

Unfortunately, not everybody shares this vision of openness. We have come to realize that ChessBase concealed from their customers Stockfish as the true origin of key parts of their products (see also earlier blog posts by us https://stockfishchess.org/blog/2021/st ... t-fritz-2/ and the joint Lichess, Leela Chess Zero, and Stockfish teams) https://lichess.org/blog/YCvy7xMAACIA80 ... -a-rip-off. Indeed, few customers know they obtained a modified version of Stockfish when they paid for Fat Fritz 2 or Houdini 6 - both Stockfish derivatives - and they thus have good reason to be upset. ChessBase repeatedly violated central obligations of the GPL, which ensures that the user of the software is informed of their rights. These rights are explicit in the license and include access to the corresponding sources, and the right to reproduce, modify and distribute GPLed programs royalty-free.

In the past four months, we, supported by a certified copyright and media law attorney in Germany, went through a long process to enforce our license. Even though we had our first successes, leading to a recall of the Fat Fritz 2 DVD and the termination of the sales of Houdini 6, we were unable to finalize our dispute out of court. Due to Chessbase’s repeated license violations, leading developers of Stockfish have terminated their GPL license with ChessBase permanently. However, ChessBase is ignoring the fact that they no longer have the right to distribute Stockfish, modified or unmodified, as part of their products.

Thus, to enforce the consequences of the license termination, we have filed a lawsuit. This lawsuit is broadly supported by the team of maintainers and developers of Stockfish. We believe we have the evidence, the financial means and the determination to bring this lawsuit to a successful end. We will provide an update to this statement once significant progress has been made.

We would like to thank our fans for their support, and encourage them to download and use the official version of Stockfish that we enjoy developing and sharing freely.

The Stockfish team"

Well Fellow Citizens An Earthquake of A Development.....Didn't See This One Coming...War Declared!! I will tell you this I am sure the The Stockfish Team is quite Annoyed with All The Fat 2 Compiles (And Believe Me There are quite a few Knockoffs of Fat F2 with "updates" coming every few days!) I think the 46mb Larger F2.bin I've been seeing around is from Chessbase? Quiet Debates are raging over This one or that one.. Plus Cfish..Raubfisch..Bluefish...Honey and Corchess are still out there also...It's Interesting and Confusing at the same time...We do need Chessbase and Also Stockfish for Obvious reasons... Hopefully some sort of Amicable Resolution Can come from this unfortunate situation..

[Alexander Schmidt]

Is this the 1st time a chess-software-licence lawsuit is filled? If not, what are some previous instances?

This is the first copyright infringement: http://chesscomputeruk.com/html/scisys_ ... years.html

Finally someone takes action against Chessbase. I really can't understand why someone here support Chessbase by buying their products since Chessbase sold Rybka and Houdini. In fact they interfere open source development and betray honest programmers.

[jorose]

In case you didn’t notice: https://stockfishchess.org/blog/2021/ou ... chessbase/

https://stockfishchess.org/blog/2021/ou ... chessbase/

[...]

Well Fellow Citizens An Earthquake of A Development.....Didn't See This One Coming...War Declared!! I will tell you this I am sure the The Stockfish Team is quite Annoyed with All The Fat 2 Compiles (And Believe Me There are quite a few Knockoffs of Fat F2 with "updates" coming every few days!) I think the 46mb Larger F2.bin I've been seeing around is from Chessbase? Quiet Debates are raging over This one or that one.. Plus Cfish..Raubfisch..Bluefish...Honey and Corchess are still out there also...It's Interesting and Confusing at the same time...We do need Chessbase and Also Stockfish for Obvious reasons... Hopefully some sort of Amicable Resolution Can come from this unfortunate situation..

I don't know much about Raubfish, Bluefish or Corchess, they may or may not be problems, I simply don't know enough to comment.

With regards to Cfish and Honey, not only are they legit with regards to GPL, that form of derivative is actively encouraged! They do not hide their origins or attempt to mislead their users. They actively and freely distribute the source code together with any binaries.

Whether or not they should be allowed on any rating lists is a separate issue and up to the decision of whomever runs each respective rating list. People will have their own opinions and the communities opinions may make certain lists more or less popular as a result, but there is no strict right or wrong.

I am pleasantly surprised about this lawsuit. The situation has been bothering me enough that I have described the situation to a couple people who have sometimes asked me why they haven't sued and whether GPL is even enforceable. Hopefully we will get a positive answer now.

[Rebel]

1. I am skeptical about a positive court outcome for SF-team. CB wasn't in compliance with the GPL the first release, hence they were forced to remove the FF2 DVD from the shop but as long as the download version contains the source code they are in compliance and they don't have broken the GPL. What they did broke is trust.

2. Lawyers are always positive, too often against better knowing.

3. I am curious about the juridical claims of SF-team, are they satisfied with the removal of FF from the shop or do they want a part of the turnover as well.

[jdart]

leading developers of Stockfish have terminated their GPL license with ChessBase permanently

Is this possible? You can sue someone to comply with the terms of the license. But since a FOSS license offers the software to anyone who complies, curing any violations should enable continued distribution, if I'm not mistaken. GPL v. 3 says "All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met."

[Harvey Williamson]

are irrevocable provided the stated conditions are met."

Perhaps this is the key phrase. It can be revoked if conditions are not met.

[Frank Quisinsky]

Hi there,

what's with all the dealers selling this product?

I think that dealers should observe the situation sensitive and should go the way customers await.
A chance for dealers to give a strong signal for the own customers.

Best
Frank

[Graham Banks]

are irrevocable provided the stated conditions are met."

Perhaps this is the key phrase. It can be revoked if conditions are not met.

There is a 30 day clause to rectify any issues if I recall reading correctly.
If they're talking FF2, there was an issue with the net being embedded with the engine when originally released, but that was fixed very quickly, well within the 30 days.

Jon may well be right, but I'm no expert.

[purechess]

I've contended that Stockfish on iOS violates GPL

Appstore adds their TOS to any app.
This isn't compatible with GPL.

But in practice many apps using SF are on the Appstore.
At least attribute and link to your source code of the app.