The U.K. Competition and Markets Authority said it has provisionally found Adobe’s planned $20 billion acquisition of collaboration-software company Figma would likely harm innovation for software used by the vast majority of U.K. digital designers.

The regulator said Tuesday that, following a detailed Phase 2 investigation, it provisionally found that the deal would eliminate competition between two main companies in product-design software, reduce innovation and the development of new competitive products, and remove Figma as a threat to Adobe’s flagship Photoshop and Illustrator products.