Gregory will lead the outdoor media company, which has businesses in Western Europe and China. In the UK, its main assets are the London Underground outdoor contract and an expansive network of buses.
He has been the managing director of Telefónica Digital’s global advertising business, responsible for the telecom giant’s media portfolio, since February 2009.
Gregory has also been the non-executive chairman of the mobile advertising joint venture Weve since September 2013, and the global board member and vice-chairman of the Mobile Marketing Association since June 2012.
Bastian Lueken, the head of Platinum Equity’s European investment team, said: "Shaun is the right leader at the right time for Exterion Media. He brings with him broad media experience from senior sales, strategic and management roles across most of the major media.
"He has in-depth knowledge of complementary and emerging technologies which will enhance Exterion Media’s ability to engage audiences. Exterion Media has many exciting opportunities ahead and Shaun will have our full support as he continues to drive and transform the business."