The lawyer you hired to help you with lawsuits over the rights to Superman runs off with documents that you say contain top-secret attorney work product and attorney-client communications.

Worse, the lawyer gives a copy of the to your opponent, D.C. Comics. You report the theft to the Federal Bureau of Investigation. A grand jury subpoenas the documents from you. You hand the docs over without making any objection. D.C. Comics sues you and demands a copy of the docs you provided to the grand jury. Have you waived privilege?

Yes. Pacific Pictures Corp. v. D.C. Comics, No. 11071844 (9th Cir. Apr. 18, 2012).