10b5 programs should have fixed action dates and/or stock prices. Too many of them include a holder's option. No idea why such things are to actionable, but I gave up a long time ago thinking the SEC actually does anything useful to control fraud.
it’s legal for insiders to exercise stock options for the explicit purpose of benefiting from an upcoming development
Unless the options are expiring I don't see that as a big deal. The only detriment to the company compared with a post-news exercise would be some reduction in tax benefit.
In your scenario, for the insider to benefit it would need to be an exercise and hold, which is a very rare transaction.