There is a three-story brick International-style addition from the 1930s with steel industrial sash on the front facade, adjacent to the tower, but the rest of the exterior appears to be original.

Knickerbocker is a term often used to describe a native or inhabitant of New York, after the original Dutch settlers of the area.

According to city assessor's records, the building was owned by the Knickerbocker Press until 1934, four years after George Haven Putnam's death.

[3] After 30 years as a publishing house, American White Cross Laboratories, moved in and manufactured bandages, gauze pads, cotton balls, and related products there until 1995.

[4][5] The building was added to the Westchester County, New York State and National Registers of Historic Places in 2000.