I criticized Amazon’s policies in a blog – their lawyers have subpoenaed me
The general rules are here: https://www.law.cornell.edu/rules/frcp/rule_45Of note is rule 45(d), which states in part:A party or attorney responsible for issuing and serving a subpoena must take reasonable steps to avoid imposing undue burden or expense on a person subject to the subpoena. The court for the district where compliance is required must enforce this duty and impose an appropriate sanction—which may include lost earnings and reasonable attorney's fees—on a party or attorney who fails to comply.