IGN spoke to Seagal who said that, "some unpleasant politics" with "certain folks, not the actors" got in the way of his participation with the EX franchise, which may be in reference to his reportedly less-than-solid relationship with Expendables producer Avi Lerner whom the actor had worked with on several direct-to-video projects previously. In any event, there's still a chance that we may see the '90s icon in an Expendables film after all.
Seagal elaborated on his potential involvement, saying, "Hopefully we've gone beyond that [the previous roadblocks]. Sly just called me the other day and said that they were still [interested]. And I said, 'Hey buddy, you're my friend, let me know.' He said he was going to send me a script."
The actor hasn't seen a script just yet, and it's not entirely clear if the conversation was a very preliminary check-in for a possible fourth film, which seems logical as they wrapped production on the third in October. However, there’s a chance that Seagal could appear in a small cameo role in The Expendables 3 if they add him in during standard pick-ups/reshoots.
The actor did turn down a cameo in the first film, though, so another possibility is that he'd show up an after-credits sequence in The Expendables 3, leading into a more central/villainous role in the next installment. Either way, he's always seemed like a no-brainer for the guns and brawn world of The Expendables.