The Brazil international, who was transferred to the Old Lady Stadium last summer, purchase clause of €40 million have been activated by the Bianconeri.
The 27-year-old Brazilian played a major role in the Massimiliano Allegri’s team that dominated Italy for their seventh Serie A title and fourth Italian Cup consecutively.
“Juventus have exercised the option for the definitive acquisition of the registration rights of Douglas Costa from Bayern Munich for EUR40 million to be paid in two financial years,” Juve said in a statement via Sky Sports.
“Juventus and the player signed a contract of employment until 30 June 2022.”
The Bianconeris also stated that the Bundesliga giants could receive an additional €1 million based on the Douglas Costa performances in the future in the team.
Costa arrived at Bayern from Ukaranian club Shaktar Donetsk for a fee reported to be €30 million in the summer of 2015, and struggled for form in first season with the German giants, which triggered his loan deal to the Serie A outfits.
While on loan from the Bavarians last season, Douglas Costa recorded the highest number of dribbles in the Italian Top Flight completing 106 dribbles, scoring six goals and provided further 14 assists in 47 appearances.