The course for the Boston Marathon does not meet two of the criteria necessary for ratification of world or American records:
- "The start and finish points of a course, measured along a theoretical straight line between them, shall not be further apart than 50% of the race distance." [i.e., 13.1 miles (21.1 km) for the ~26.2 mile (~42.2 km) marathon distance]
- "The decrease in elevation between the start and finish shall not exceed an average of one in a thousand, i.e. 1m per km." [i.e., 42.2 m for the ~42.2 km marathon distance]
The Boston course has an endpoint about 24.3 miles (39 km) from the start point, and the endpoint is also 459 feet (139 m) lower than the start point.
Due to the fact that the Boston course is a net downhill in excess of the limit allowed by the world record setting body.
His time is recognized as the fastest marathon ever...but not the world record.
Because Dennis Kimetto ran 2:02:57 in Berlin on September 28, 2014.