The 16-times champion jockey was riding Sharadiyn in the Betfair Supports Spinal Research Handicap Hurdle when he and eight other riders ignored a member of the groundstaff waving a yellow flag, which denotes a race should be stopped.
Head groundsman Ian Ward attempted to void the race as the stricken Ashburton Lad was lying between the third-last and the penultimate hurdle.
Ward was working within his remit, but nine jockeys still finished the race, with Cunning Clarets, ridden by Brian Hughes, first past the post.
The offending riders — Hughes, McCoy, Graham Lee, Danny Cook, Denis O’Regan, Alex Voy, Jonathon Bewley, Paddy Brennan and Brian Toomey — will be sidelined between October 26 to November 4.
Dougie Costello’s mount, Favours Brave, pulled up, the Tom Messenger-ridden Glorybe refused to race, while Campbell Gillies was on Ashburton Lad.
Costello, Messenger and Gillies therefore escaped any punishment.
The suspended jockeys will miss the Charlie Hall meeting back at Wetherby on October 29.
A sign in the weighing room, explaining the yellow flag procedure, reads: “If at any stage during a race you see an official waving a yellow flag, this is the sign to immediately pull up.”
The stewards also held a further enquiry into why the stop-race flag had been deployed, but forwarded their evidence on to the British Horseracing Authority (BHA).
Wetherby racecourse chief executive Jonjo Sanderson said: “Fiona (Needham, clerk of the course) was trying to contact Ian Ward, our head groundsman, on the walkie-talkie.
“Unfortunately, for some reason Ian could not hear her. Ian was concerned that the runners would not be able to get past the stricken horse and he made a judgment call.
“In his roll as head groundsman he is well within his rights to make such a call. Ian has not made a mistake, it was a judgment call.”
Cook said: “I’m very annoyed and very frustrated. I only caught a glimpse of the yellow flag.’’
McCoy and the other guilty jockeys refused to comment.
Meanwhile Natalia Gemelova was handed a seven-day ban at Lingfield for falling foul of the BHA’s stricter whip rules as the debate rumbled on yesterday. A maximum of seven strikes are allowed during a Flat race, and no more than five during the final furlong, and the transgressors can be suspended as well as losing their riding fee and any prize-money percentage.
Although there appeared widespread acceptance of the changes from trainers and jockeys when they were announced, dissatisfaction is growing.
Richard Hughes and Kieren Fox were punished heavily at Windsor on Monday, while Gemelova was given a seven-day holiday from her ride on second-placed For Life in division two of the News International Classified Claiming Stakes.
Gemelova must sit out October 26-29 and October 31, as well as November 1-2. “I tried my best to stay within the rules, but it’s harder than you think,” said Gemelova.
“I waited as long as I could before picking up the whip and I’m just going to have to be more careful. I think there should have been a trial period, not just ban us straight away.
“We’re out there making a living, we love our jobs and don’t want to hurt the horses, but they should have given us a warning.”
Pat Cosgrave was later given a five-day ban when finishing a short-head second on Marcus Antonius in the Smiths News Handicap.
Cosgrave was found to have used the whip eight times.
William Buick was also handed a five-day ban at Kempton.
Buick finished fourth on Ghostwriting for his boss, John Gosden, in the Betdaq Mobile Apps Conditions Stakes won by Kinglet.
The stewards found that Buick had used his whip with excessive frequency and banned him from October 26-29 inclusive and October 31.
Elsewhere Irish jockey Cathy Gannon has sustained a fractured femur after suffering a bad fall before the opening race at Nottingham yesterday.
Gannon was unshipped from Forever Janey on the way to the start for the Winning Forecast DG Taxis 0115 9500 500 Maiden Auction Stakes.
The jockey now faces a lengthy spell on the sidelines.