So when adjusting the cost basis, do I go with what's on the supplemental or what's in box 14 of W-2? Basically the question comes from having sold short term all the RSU's identified as ordinary income on the W-2 but somehow the brokerage generated supplemental form does not show that full amount on the adjusted cost basis. Not sure why. But of course, withholding was based on the full vested amount noted on the W-2. From what I've been seeing, it looks like I could adjust the cost basis to what's reported on the W-2 which generates a bigger capital loss than using the adjusted cost basis on the supplemental. Any thoughts?
