The controversy is not so much with these engines, but rather with the "free," "open source" engines that are cropping up. There are many of these as well, led by what's known as the IPPOLIT family, including RobboLito, Igorrit, IvanHoe, FireBird and Fire. Some have claimed that the IPPOLIT engines are nothing more than decompiled versions of Rybka that have been tweaked (for better or worse) and tossed onto the market. Last I checked the IPPOLIT authors were an anonymous group hailing themselves as the "Decembrists."
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