The FBI has destroyed the files it kept on former New York Times publisher Arthur Ochs Sulzberger because they didn't pass historical muster. The New and Improved Veg-O-Matic II, however, remains safely in the Smithsonian's permanent collection.
The files in the dossier on Sulzberger (hot damn we finally got our chance to type "dossier") were created when President Nixon ordered J. Edgar Hoover to dig up dirt on Sulzberger during the fight over the Pentagon Papers (“do everything we can to destroy the Times"), and were sought by a Capital New York reporter in a FOIA request.
The reporter was then referred to the National Archives, which answered the reporter's additional FOIA request with the statement, “The FBI has informed us that the file was destroyed on December 1, 2011, according to an authorized agency records disposition schedule.”
The agency often destroys records, and notes that because their archives are so vast, the determination on whether to keep some and toss others is a balance of “historic preservation with the explosion of modern records and limited resources to preserve these records.” Files the FBI kept on Rosa Parks were also destroyed.
There's still a chance that some records on Sulzberger exist in the Bureau's "special file room," as files on Walter Cronkite later turned up even after the FBI claimed they were destroyed. Sulzberger, who died last fall, famously made the call to publish the Pentagon Papers, later saying of the decision that would earn the paper a Pulitzer,