Naman Ramachandran The merger of social media giant Facebook and Giphy, the largest provider of GIFs, has run into a roadblock from the U.K.’s Competition and Markets Authority (CMA).Following an investigation, the CMA has provisionally found that Facebook’s takeover of Giphy will negatively impact competition between social media platforms.The deal is valued at $400 million, Variety understands.If the CMA competition concerns are ultimately confirmed, it could require Facebook to unwind the