If you've ever seen the documentary The King of Kong, you'll recognize the name Billy Mitchell. He is the focus of the film, as he theoretically goes for 2 separate 1 million + point scores on the game Donkey Kong. For over a decade, Mitchell has been recognized as the first player ever to achieve the 1 million point barrier on the game. His scores have been recognized by Donkey King Forum, Twin Galaxies and Guinness World Records.
In February, Donkey King Forum removed Mitchell's high scores following an analysis of the footage submitted to support the score. After watching the video frame-by-frame, it was discovered that there was artifacting during level transitions. This is a scenario that only exists on early versions of the Multiple Arcade Machine Emulator (MAME) system, and not on the original arcade hardware. High scores, however, can only be counted if achieved on arcade hardware.
Following this revelation, Twin Galaxies did their own investigation, and agreed with DKF's analysis. They also discovered what appears to be inconsistencies in the game itself, suggesting that the footage is actually cut together from more than a single run, meaning that the score was completely manipulated, and therefore invalid. Twin Galaxies then removed the high scores from their board and banned Mitchell from appearing in the future, due to a decade of lying about his scores.
This left him with a single forum that recognized his score: Guinness. Unfortunately, Guinness uses Twin Galaxies as part of its verification team for videogame scores. Shortly after Twin Galaxies dismissed the scores, Guinness did, as well, leaving Mitchell with nothing but a documentary about him not accomplishing anything.