Something’s afoot at 52 Clark Street, the 141-unit prewar apartment building in Brooklyn Heights. The building is currently a rental, with some of the apartments still covered by rent stabilization. All that may start to change very soon, if an email we received from a resident turns out to be on the money. According to the email, the tipster has received a couple of notices from the landlord (who’s owned the building since 1999) that her lease would not be renewed. Upon calling the management office, she was told that none of the leases in the building were being renewed. The only possible explanation we can think of? You guessed it, conversion. GMAP P*Shark