...I would expect both sides to issue some sort of press release about such a stipulation, but maybe not.
Non-announcement could have been a condition of such a stipulation, although it’s not clear to me what benefit accrues to anyone from keeping it secret. The best answer I can come up with is not especially convincing: the parties may have thought going public with a no-launch stipulation would trigger the wrath of the FTC, a bureaucracy whose kneejerk reaction is to oppose any agreement it perceives as impeding the launch of a generic drug.
The speculation about a no-launch stipulation may seem far-fetched, but I think the sell-side analysts are being derelict in not at least contemplating such an outcome that would be highly bullish for MNTA.