There is no patent clause now. Assuming some FB patent has crept its way in one of their open source, if a company sues FB for patent infringement, FB would be able to counter-sue for copyright infringement due to the suing company's use of FB's open source.
"As long as you don't sue us, we won't sue you" kind of a deal. If the above scenario is true, it seems there is no de facto change beyond the political one.
Anyone with more legal expertise able to disprove this scenario?