TP exercised and sold ISO shares on the same date. The total FMV of share on the date of the option was exercised (Box 4 of Form 3921) was $24,847 but the cost basis was $24,748 (Box 1e Form 1099-B).

The bargain element (FMV – Exercise price) already included in Box 1 Form W-2.

There was a difference of $99. In reporting into Form 8949 Part 1 Box A, which figure should be used: $24,847 Form 3921 or $24,748 Form 1099-B as both are reported to the IRS?

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