Ah, so The Martin Agency was not the entity he called "an outside agency" which "pitched us a bunch of standard super bowl ad ideas" in the second tweet of the thread?
https://twitter.com/brian_armstrong/status/14956361148243804...
My guess, which may be a tad speculative, is that there is an ongoing, but previously-confidential, dispute between Coinbase and the agency over whether and how much the former owes the latter for the work they did.