Nike’s 2017 Breaking2 marathon attempt had an official finishing time of 2:00:25.
Eliud Kipchoge ran the distance at the Autodromo Nazionale Monza in Italy on May 6, 2017. He missed the project’s two-hour target by 25 seconds, but his performance was far faster than the official marathon world record at that time.
The attempt was designed as a controlled experiment rather than a standard championship race. Pacemakers rotated in a formation, a support vehicle helped maintain pace, and the course was selected for favorable conditions. Those features meant the result was not eligible for official world-record recognition.
Kipchoge later broke the two-hour barrier in Vienna in 2019, recording 1:59:40.2 in the Ineos 1:59 Challenge. That later result also was not ratified as an official record.