The Hart-Scott-Rodino waiting period for Blackboard Inc.'s proposedacquisition of has expired,the company said July 25.

The end of the waiting period satisfies one of the conditionsrequired for the completion of the tenderoffer for Higher One's shares. Under the tender offer, which expiresat 9 a.m. ET on Aug. 4, Blackboard offered to purchase the shares for $5.15 pershare.