I went through the K when he did it and didn't see others nearing the deadline, as information those were not "warrants" they were "Options" two different animals completely. Options are taxed as regular income so the ones he sold covered his nut on the taxes. Lightwave does not have a lot of executives with a lot of those options. Even if there are some, I don't see it as a worrisome issue. They have earned it.
I did a post on this if anyone cares to figure it out look through my posts.