This is a lot of legal knowledge. But not $50bn worth. I'm guessing the real story is DocuSign is trying to worm its way into being a de facto monopoly, maybe by paying enough lobbyists, and the $50bn is the bet that they'll be successful. Multiplied up a bit by the fact that we've been living in a free-money world, where castles in the air get pick-a-number valuations.