(c. 1060-c. 1135)
French Tosaphist, son-in-law of Rashi. He lived with Rashi in Troyes, but later moved to Remerupt where he founded a bet midrash. He wrote commentaries to the Talmud. Halakhic statements by him were quoted by his son Jacob Tam in his writings.
Dictionary of Jewish Biography. Dan Cohn-Sherbok.