If your stock option plan allows you to "early exercise" (exercise before the options vest--this gives you restricted shares that vest on the same schedule as t

If your stock option plan allows you to "early exercise" (exercise before the options vest--this gives you restricted shares that vest on the same schedule as the options you exercised) then you can file an 83(b) for those restricted shares. Edit: I should add that this only matters for AMT purposes. If you early-exercise ISOs then the 83(b) election doesn't change anything for regular income tax, but does effectively accelerate your AMT income.