@CertifiedPublicAssistant
IRS requires details of your SELL transactions to be supplied on some Form 8949,
or on your other forms (e.g. consolidated 1099-B) which have the same information and in the same manner as Form 8949.
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If your Form 8949 is 20 pages, that tells me you supplied the transaction details on your tax return already.
There is no reason to mail the details in again a second time.
