Shielded by the Trust, Biograph had been slow to enter feature film production. It contracted with the theatrical firm of Klaw & Erlanger in 1913 to produce movie versions of the latter's plays. Its first released feature, "Classmates", came out in February 1914, after 69 other American features had been released in 1912–13. Distribution was hampered by Biograph using a special perforation pattern on the Klaw & Erlanger features that was incompatible with standard projectors, forcing exhibitors to lease specialized equipment from Biograph in order to show the films. With the exodus of the studio's best actors to Griffith, Biograph was unable to develop a marketable star system as the independent companies were doing, and after the Trust's fall, Biograph found itself behind the times. The Biograph Co. released its last new feature-length films in 1915 and its last new short films in 1916. Biograph spent the remainder of the silent era reissuing its old films, and leasing its Bronx studio to other producers.