There seems to be quite a lot of controversy over the lineage of quite a few of the top chess engines, from what I recall reading. I can't find the article I'm

There seems to be quite a lot of controversy over the lineage of quite a few of the top chess engines, from what I recall reading. I can't find the article I'm remembering this from right now, but I think it was focused on [a] decision to disqualify Rybka from some rankings. Ippolit stands accused of using decompiled parts of Rybka, Rybka itself may[2] be using bits of Fruit, and possibly others. I don't know enough to comment about the strength of the various allegations, but there are definitely conflicts over the exact authorship/heritage of a lot of the top performers. [2] https://en.wikipedia.org/wiki/Rybka#Controversy https://en.wikipedia.org/wiki/Rybka#Controversy