UEFA say they will probe the sponsorship deals for clubs like PSG and Manchester City so they're in compliance with the new financial fair play laws.
UEFA published its annual benchmark report which warns two English clubs - understood to be Manchester City and Chelsea - are among 46 across 22 European countries who could fall foul of its financial rules based on 2009-2011 figures.
UEFA general secretary Gianni Infantino said: "Everyone, including PSG, know they have to demonstrate [the deals] are without cheating and that will be submitted to panels.
"We have a regulation which speaks about fair value of deals and the fact that a related party cannot just inject money into a club directly or indirectly."