I would post this in DE as well. Even though Comcast is a Denver company, this obviously appears to be an out-of-state subpoena from DE out of either a criminal investigation or a civil case. Technically, Comcast can file a Motion to Quash the Subpoena. However, if you file a Motion to Quash the subpoena, what are the privacy interest grounds that you are going to seek protection for other than possible illegal conduct. You need to state why you have an expectation of privacy in cable service and internet service communications. Otherwise, the Court will error on the ground of at least inspecting the documents in chambers by the judge and the judge will determine if they are relevant to the investigation and can be disclosed.
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You must file a Rule 45 (below) motion to quash and state your grounds for the motion such as ambiguous, untimely, etc. The fact that you live far away does not factor in here since this is a national company with computer records easily attained. Please consult with any attorney right now as these types of lawsuits about downloading content can get real mean real fast.