According to this report, incorrect information provided by dispatchers to the flight crew with caused this UAL 737-900 to take off at a weight about 20,000 pounds (9,071 kilograms) heavier than than pilots believed.
United sent pilots a weight estimate that assumed the coach section of the Boeing Co. (BA) 737-900 was empty when it was full. ... While the pilots, who didn’t catch the mistake, had difficulty getting the jetliner airborne, the plane wasn’t damaged and the flight was completed without incident. ... Boeing’s 737-900 models can take off weighing as much as 187,700 pounds (85,141 kilograms), according to Boeing’s website.
Given that the pilots obviously knew how much fuel they were carrying, and that they had a full load of passengers, it seems concerning that they didn't notice such an anomalous figure for total weight. Note that this instance seems different from the Emirates MEL flight where an incorrect weight was inadvertently keystroked into the FMS. Here the provided weight sheet was wrong.
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United Overweight Takeoff on Computer Mistake Prompts Changes - Bloomberg