The general counsel of the Association of National Advertisers says there have been settlements stemming from audits of media agency contracts. The CEO of the 4A’s, the leading U.S. agency organization, says nearly a hundred audits have taken place, but agencies have yet to give any money back.

The fact is, both of them are probably right, and that’s part of what’s wrong with U.S. media buying and client-agency relations today. Since the U.S. media rebate issue exploded in 2015, rumors of audits and legal settlements between media agencies and marketers have bubbled up consistently. An investigation into the issue by Ad Age conducted over several months, including interviews with dozens of industry players, indicates that those audits and settlements really are happening. But people familiar with the matter say but they may remain secret forever—because neither side has much interest in making them public.

Read the full Ad Age article here.