A subpoena is a request for documents to be provided at a date and time in the future. In other words, you do not have to immediately turn over the records requested in the subpoena. If you or your company receive a subpoena, you should immediately contact a lawyer. Your lawyer may be able to extend the time frame to respond, reduce the scope of the subpoena, or file a motion to quash the subpoena.
It is important to distinguish the difference between a warrant and a subpoena. A warrant is executed by law enforcement in the context of a criminal case and states the time, location, and items that can be collected pursuant to the warrant. Once a warrant is issued there is nothing that can be done to stop a search. If law enforcement indicates they have a warrant, you should comply immediately and ask to contact an attorney. Law enforcement is not required to immediately show you the warrant, however they are not allowed to lie about having one. Legal challenges to the warrant and/or its execution can be brought later.