It is not grounds for objection that the information sought will be inadmissible at the hearing if the information sought appears reasonably calculated to lead to the discovery of admissible evidence. All discovery is subject to the limitations of paragraph (d) of this section.
If a request, response, or objection is not signed, it shall be stricken unless it is signed promptly after the omission is called to the attention of the party making the request, response, or objection, and a party shall not be obligated to take any action with respect to it until it is signed.
19 C.F.R. §210.27