This is a better analysis than most, but it is unlikely that a court analyzing this would stop there. The court would probably use the Abstraction/Filtration/Co

This is a better analysis than most, but it is unlikely that a court analyzing this would stop there. The court would probably use the Abstraction/Filtration/Comparison test. Take the code, filter out the abstract concepts, the purely functional expression, and finally the short words and phrases in what was left. Some other courts would impose a further filter based on fair use and interoperability. Take a look at the diff and apply some of those filters in your mind. After all those filters, I am unsure what, if anything, would be left. EDIT: I had thought that this might be a case of parallel development, but Rick Beckman (former dev for Thesis) just posted that there was copy-paste from WordPress core - he did it. (http://ma.tt/2010/07/syn-thesis-1/#comments http://ma.tt/2010/07/syn-thesis-1/#comments, Rick Beckman @8:41) Although that doesn't make it completely open-and-shut, it makes it significantly more likely that Matt/WP would prevail.