I am having to get ramped up on this right now as my company is filing. I'm not 100% positive, but, I believe if you exercise and sell in a single transaction, you're going to get hit with ~40% short term capital gains tax. Holding the exercised stock for a year will reduce the tax hit at sell time to ~22% long term gains.
Yeah. The right time to exercise when a company is filing is like...a few years before, when the shares were pretty much imaginary and you weren't standing to be taxed for imaginary wealth (why I once agonized over buying 25 cent shares for 700 bucks in a company 4 years away from an IPO, I have no idea--it's either lost money or free cash. Assume it's lost money and you're either right or happily surprised a few years down the road; both aren't such bad outcomes).
You've likely heard this, but one thing you might want to look at is a hybrid transaction (I think they call this a "cashless transaction"); exercise and sell enough to cover taxes and to purchase anything you've got available to exercise (to hold for another year).
You may net less (or much less) a year from now waiting for long term federal tax rates vs selling now - if the stock price falls rather than remaining flat/rising.
I've come to the realization that you're right, jen_h and mjs00. I'll likely be doing the cashless transaction (if offered). Basically, I didn't play this one as well as I could have and am trying to find a way to recoup now. I think it's a bit late and I should take whatever's on the table when the lockout ends (assuming there's something left)
A bit of advise, you need to compare between capital gains vs stock loss. Most problems come when the stock is losing 40% of its value, and still keep it in order to avoid capital gains, ended up losing even more.