I worked on the consulting project in 1990 that famously resulted in Continental Bank closing down its 70+ lawyer department and by outsourcing satisfying its legal needs with Mayer, Brown & Platt. That decision was the page-one headline on the inaugural issue of Corporate Legal Times, and it triggered much controversy.
Dramatic, but still old hat since it turns out that in 1920, Karl Llewellyn “joined the legal department of the National City Bank, which at the time was transferring its legal department to the Wall Street law firm of Shearman and Sterling [Cited in Ajay K. Mehrotra, “Law and the ‘Other’: Karl N. Llewellyn, Cultural Anthropology, and the Legacy of The Cheyenne Way (Law and Social Inquiry, Vol. 26, Summer, 2001 at 748)].
Probably the Greeks invented law department outsourcing.