The A and Eagle trademark is the most widely recognized symbol
of Anheuser-Busch Companies, Inc. and Anheuser-Busch, Inc. First
used on the company's beer products in 1872, the symbol was not
registered with U.S. Patent Office until 1877. The trademark (No.
4623) soon became widely recognized as a symbol of quality
throughout the world.
http://www.anheuser-busch.com/historyAEagle.html
Thanks for an easy question
Thom