Ducky911 is pretty close and I'm assuming the S corp sale referenced was for no "gain". The question is do you have a gain or did you sell your percentage at no gain (other than previously taxed basis adjustments)? A sale of the whole amount is probably easier to calculate tax wise... so your basis on the day of the sale should include profits and losses up to that date. You may need or want more information from the accountant regarding that.
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