When a form or signature is missing from a return the IRS sends Letter 12C to ask you to sign the declaration or send the missing form so they can process your return. This is very similar to Letter 4612C but it should not be confused with Notice CP12. For old returns which have recently been filed (late) and missing a signature the IRS sends Letter 2416C.
This is not really a Return Error. You simply omitted a form. You did not make a miscalculation. It is also not an Audit. The IRS could audit the return later.
Respond to Letter 12C
If the IRS is asking for a signature, just sign the attestation clause attached to the Letter 12C. Keep a copy for yourself & send the original to the IRS by certified mail at the address on the Letter 12C.
If the IRS is asking for a missing form or schedule, you simply need to copy & send it to them at the address on the Letter 12C. The letter invites you to fax it to the IRS, with instructions if you are inclined to do so. You probably don't need a lawyer & could use the services of TaxHelpReturns instead to prepare the form(s) necessary & respond to the IRS.
If you have lost the form or schedule the IRS is requesting, you may request another one from the provider or your tax return preparer.
If you disagree with the IRS or are confused by letter please follow the Prep Steps. Contact Mr. Hopkins so we can work on a solution & Action Plan!
IRS requesting signature: