The 17-year-old has scored three goals in eight games for Werder's Under-19 side this season, having scored 17 goals in 26 matches for their Under-17s last term.
Although he is uncapped by Germany at Under-17 or Under-19 level, reports claim Philipp is regarded among the best young players in the country.
Sky Deutschland says Liverpool and Spurs have been in talks to sign Philipp - something Werder youth chief Bjorn Schierenbeck has acknowledged.
"I do not want to exclude it. However, I do not know how concrete the interest is," said Schierenbeck. "We've already showed him in his conversations about how his career could look at Werder."
Tottenham were linked to Werder's Denmark international midfielder Thomas Delaney as well last week.