This information is located at http://www.oneworld.com
Click on American Airlines, then choose AAdvantage Platinum and click "show me."

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AAdvantage Platinum
Platinum is equivalent to oneworld Sapphire

AAdvantage Platinum members will be entitled to the following benefits across the oneworld network:

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Preferred boarding and entrance to all of the oneworld airlines' Business Class and airport lounges when traveling internationally*, regardless of the class of service flown on that day

* Lounge access is not available when traveling solely on North American itineraries. North American itineraries are defined as travel within or between the U.S., Canada, Mexico (with the exception of Mexico City), the Bahamas, Bermuda and the Caribbean.

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