Different contributor here. The original contributor has exited the conversation. Please permit me to assist.
1. There is no standardized legal procedure for the requesting party to cancel, amend, withdraw, retract, limit, etc., a subpoena. However, as any valid subpoena is always a burden on the subpoenaed party, an attorney, can simply call the party subject to the subpoena, and tell them to ignore the document, as it was sent out in error. A follow-up letter confirming this would be sufficient to permit the subpoenaed party to rely on the letter withdrawing the subpoena.
2. The letter could also state that the subpoenaed party may ignore various sections of the subpoena, as a means of limiting the required production.
3. Nothing need be filed with the court in order to remedy this matter. Undoubtedly, your attorney either wants the subpoenaed materials, even if you do not, or she believes that the cost of limiting the subpoena's requirements will be as much as the cost of dealing with the documents produced as a result.
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