The Kenyan runner exceeded Ethiopian record holder's women's marathon global best by about 120 seconds at the Chicago Marathon in the year 2024.
Female long-distance global champion the athlete has been suspended for three years after the Kenyan admitted to doping rule violations.
Chepngetich was provisionally suspended in the seventh month following a failed test for a banned substance - a banned diuretic often utilized as a masking agent - on March 14.
The athlete's accomplishments which pre-date that test - including her global best performance of 2:09:56 in Chicago in October 2024 - will still stand.
The Athletics Integrity Unit (AIU) had requested a four-year ban but the 31-year-old penalty was lowered to 36 months because she admitted to the infractions.
Nonetheless, the AIU will keep examining evidence from Chepngetich's mobile device which it found indicate "a reasonable suspicion that her positive test may have been deliberate" - including messages from as early as 2022.
"The case concerning the positive test for the substance has been resolved, but the AIU will continue to investigate the suspicious material found on the runner's device to determine if any other violations have occurred."
When questioned in April by the integrity body, the marathoner, the first woman to run a marathon in less than 2 hours 10 minutes, was unable to give an reason for the failed test.
While the substance has a lowest detectable limit of 20 ng/mL in samples, Chepngetich's test showed an estimated concentration of 3,800 ng/mL.
Small amounts of the diuretic under the detection threshold were also identified in a test collected from the runner 14 days prior, on February 28.
At a later interview on July 11, the record holder was shown the aforementioned questionable proof obtained from her mobile. In the meantime, accidental exposure had also been disproven by the AIU.
Chepngetich altered her story on July 31, claiming that she had taken her domestic worker's medication - labeled as being HCTZ - after becoming ill two days before the positive test.
The AIU had "serious reservations about the credibility of the new version of events" and, in the framework of the sport's doping regulations, such "carelessness" is deemed "indirect intent, for which an increased four-year penalty is applicable".
An standard 12-month decrease was applied after Chepngetich confessed to the doping rule violations inside the specified 20-day period.
The 36-month suspension started on 19 April - when the athlete accepted a voluntary provisional suspension - with the runner's performances, awards, titles, appearance and prize money since 14 March forfeited.
"Nobody is above the rules."
"While unfortunate for those who had faith in this runner, this is how the process is designed to operate."
"The road-running industry should be commended for jointly supporting doping prevention able to revealing substance abuses committed by top competitors in their events."
Elara Vance is a tech journalist with over a decade of experience covering AI, cybersecurity, and emerging technologies across Europe.