Virtual Tape Storage (deep & legally immune)
Given the retrieval time for anything in ACME's deep storage can take a full day, I'm guessing that involves a guy driving a golf cart deep into the Blue Ridge Mountains to fetch a tape of encrypted data to which a known key may no longer exist. And the idea that such data can & should be deleted for "legal reasons" is absurd. A reasonable NDA (and any related retention clauses) will explicitly speak to the aforementioned archival factors.