Document inspection
From LegalLanding
As allowed by FRCP Rule 34, during discovery a party may demand an opportunity to inspect and copy documents and other tangible things possessed by other parties. The rule also authorizes entry onto property for the purposes of testing or measuring, although courts might be more restrictive with this. Electronically-store information is included, although documents need to be described with “reasonable particularity.” However attorneys often rely on a categorical description. Requests are inexpensive to prepare, and like interrogatories may only be sent to parties. The criticism is that it is too easy to put the recipient to a lot of work.
After a party requests the documents, the other serves a written response specifying what will be made available or objecting to some or all of the requests. The other party is only required to send those that are within its “possession, custody, or control.” Control, though, can mean that the party has influence over the possessor (Societe Internationale v. Rogers (1958)).
If the request is to a nonparty, then a subpoena is required, and the requesting party must take reasonable steps to avoid imposing undue burden or expense.