The New York Attorney General’s office is investigating online ticket re-sell sites for selling tickets to Bruce Springsteen shows, even though the tickets have yet to go on sale for the public.

New York Attorney General Eric Schneiderman sent letters to StubHub, TicketNetwork and Vivid Seats on Monday, telling them that they have to pull “speculative” listings of tickets for The Boss’ 2016 tour.

According to Reuters, Schneiderman also asked their executives to meet with investigators to figure out how they can stop tickets being sold by users who don’t actually have the tickets in hand.

TicketNetwork told The Associated Press that it has already pulled speculative ticket listings. StubHub doesn’t think there are “speculative tickets” on its site, but will review the attorney general’s letter.

Last week, Springsteen announced his 2016 tour to support The Ties That Bind: The River Collection, a massive box set filled with previously unreleased recordings for 1980’s The River. The tour starts on Jan. 16 at the Consol Energy Center in Pittsburgh and tickets go on sale Friday.