Limit is now posted on the AA OW award page:


Valid: All eight oneworld carriers may be used on one award as long as the mileage and segment maximum is not exceeded (see distance range). Travel must include at least two one world partners other than American Airlines, American Eagle or AmericanConnection, and effective January 1, 2005 may not exceed 16 segments.

Routing: Members may fly unlimited segments and may stop in each city once, but may not connect in the same city more than twice. Passengers may not stopover or connect in the city where travel originated.

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