LAST ASSIGNED ALTITUDE
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Last Assigned Altitude
The last altitude/flight level assigned by Air Traffic Control (ATC) and acknowledged by the pilot. (FAA4)
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LAST ASSIGNED ALTITUDE
The last altitude/flight level assigned by ATC and acknowledged by the pilot.
(See MAINTAIN.)
(Refer to 14 CFR Part 91.) 

Source: U.S. Department of Transportation, Federal Aviation Administration (FAA).