American AAdvantage has two banks issuing credit cards to members in the U.S.: Citibank and Barclays. Citibank advertises online, through direct mail, and in American’s club lounges. Barclays advertises in the airport (but not within 100 feet of a club) and on flights.
The Barclays small business card is still new and hasn’t ever offered 50,000 miles before though I imagine after this offer ends we’ll eventually see it back.