Earlier quoted context omitted.
I think that the proposal is, much as with taxes on realized gains and losses , unrealized losses would be allowed to offset unrealized gains and be carried forward if there was an excess of losses.
Ouch. If I understand you correctly, this is then a really awful scenario for founders. As a founder, my only assets were the stock of my company . I don't own any other stock, certainly none that would go thru the roof over a year or 2. If the company goes south after a hot streak, I end up with excess unrealized losses that I can't use, because I have no other assets with unrealized gains to book against my carryfo…
It makes having all your eggs in one basket (very slightly) worse than the generally bad idea it already is (if its a billion dollar basket so that you qualify for this treatment in the first place.)
But if all your eggs are in that basket, either the company bounces back later or you are wiped out anyway, so its not that much of a change from the status quo in that respect.
Not that I like the proposal, mind you