The AC Company also known as the American Colortype Co. issued lithograph type stereoviews on very poor cardboard stock from roughly 1900 through the 1920’s. These lithographs are less abundant than most, but are still commonly seen. The company produced approximately 250 titles of decent photographic quality; only the card stock was poor. The coverage of their set was broad, including much of the U.S., Canada, and a noteworthy series of views of the Klondike in Alaska dated 1925. In addition the company produced coloring books, paper dolls and advertising items. They were one of the last producers of lithograph stereoviews. Views were issued to at least 1927.

Their only known Yellowstone view shows a herd of Buffalo in the Mammoth Hot Springs area. It is relatively common and does not hold much collector value today.