How must objections to a subpoena for attendance be made?

Objections to a subpoena for attendance must be made by timely motion under Rule 45(e)(2) primarily because this rule outlines the formal process for contesting a subpoena. The procedure ensures that any objections are documented and handled through the appropriate legal channels, which provides clarity and legal recourse for both the party issuing the subpoena and the one objecting to it.

Filing a motion allows the court to address the objection systematically, ensuring that due process is followed. This mechanism also creates a formal record of the objection and provides the court with the necessary context to make an informed decision based on the reasons presented in the motion.

The other choices do not align with proper protocol. For instance, making objections orally in court does not provide a formal record or the specificity required to address the subpoena's validity. Written notice to the other party, while it might inform them of the objection, lacks the weight and procedural follow-through afforded by a motion. Informal conversations are not recognized within the legal framework for objections and do not hold any legal authority or documentation. Thus, following the formal process outlined in Rule 45(e)(2) is essential for a valid objection.