The Philadelphia centres have signed with Eisbaren Berlin of Germany's top league for the duration of the NHL lockout, according to ESPN.com.
The website says veteran agent Pat Brisson, who represents both players, confirmed the signings.
Giroux was third in NHL scoring last season with 93 points (28 goals, 65 assists).
Briere had an off year by his standards, with 16 goals and 33 assists in 70 games.
With Giroux heading to Berlin, four of the five top scorers have headed overseas during the lockout. Evgeni Malkin and Ilya Kovalchuk have signed with teams in the Russian-based KHL while Jason Spezza is in Switzerland. Only Steven Stamkos has yet to make overseas arrangements.