Unilever, O2 and Sky and several popular U.K. platforms have all signed on to a blockchain pilot aiming to improve digital ad transparency
Source: https://cointelegraph.com/news/unilever-o2-and-sky-join-blockchain-pilot-for-digital-ad-transparency
Unilever, O2 and Sky Join Blockchain Pilot for Digital Ad Transparency
November 12, 2019
CoinTelegraph