We provided a block in this section for the witness signature, address, and phone
                  number. We provided a second block, to the right of the first block, for the signature
                  of a second witness, if required.
               
               When we attest to the claimant’s signature on Form SSA-827, we document the attestation
                  in the witness box see DI 11005.056.
               
               If the claimant signs by mark, the witness signature is required and the witness block
                  must be completed.
               
               IMPORTANT: If the field office (FO) receives a non-attested Form SSA-827 without the signature
                  of a witness, we continue to process the claim. Do not delay the claim to seek the claimant's witnessed signature unless the claimant signed Form SSA-827 by mark or the FO knows from experience that certain
                  sources require a witnessed signature.