The Stockfish project reported about achieving Agreements in the trial with the CHESSBASE company, which was accused of violating the GPLV3 license due to the inclusion of Fat Fritz 2 and Houdini 6 codes from the free chess engine stockfish without opening the initial texts of the derivative work and without informing customers about the use of the GPL code. The agreement provides for the cancellation of the CHESSBASE CHISSBASE GPL license to Stockfish code and providing this company with the opportunity to distribute its according to.
, within the framework of the reached agreement, Cheessbase will stop selling chess programs that use the StockFish engine and notify customers about this through the publication of information on its website.
Existing customers will be able to continue the use of already purchased programs, and will also be able to download already purchased copies if the Chessbase brings the loading process in line with the requirements of the GPL.
A year after the conclusion of the agreement, the developers of StockFish will cancel the review of the GPL license and provide the opportunity to use their code with the company Chessbase, which recognized the significance and potential of free software and has given the obligation to observe its principles.
GPL provides for the possibility of recalling the license from the offender and terminating all the rights of the licensee provided to him by this license. In accordance with the rules of termination of the license adopted in the GPLV3, if the violations were identified for the first time and eliminated in 30 days from the date of notification, the license rights are restored, and the license is not fully responded (the contract remains not violated). Rights are immediately returned in the case of elimination of violations if the copyright holder has not notified violation within 60 days. If the deadlines have expired, then a license violation can be interpreted as a violation of the contract for which the court can be obtained.
To prevent possible violations in the future, a separate employee will be appointed in Chessbase, who will monitor compliance with the requirements of the GPL. The company will also create a site Foss.chessbase.com, which will publish information about products using open code. In addition, Chessbase will open under the GPL or compatible license for the implementation of neural networks, supplied for use with Stockfish. The agreement does not provide for financial compensation and compensation for damage, since the Stockfish project team presents a non -profit community that has achieved the observance of the GPL and its rights.