Newcastle United agreed to a future sell on clause on Bruno Guimarães in order to secure his services.
French side Lyon will also be entitled to a bonus package should Newcastle stay up and progress in the next few years.
After landing the Brazil international, Lyon stated: "Olympique Lyonnais announces the transfer of Brazilian international midfielder Bruno Guimarães to English club Newcastle for a total amount (including bonuses)* of €50.1 million, as well as a 20% sell-on fee.