Christophe Soumillon has been sacked by the Aga Khan after the jockey pushed a rival out of the saddle.
The top owner made the announcement in a statement on Tuesday morning, four days after the incident at Saint-Cloud.
Soumillon caused widespread discontent in the industry when he elbowed Rossa Ryan in a race and he fell. The rider was fortunate not to be seriously injured – and Soumillon was handed a 60-day ban.
But as it only starts from October 14, the 41-year-old was free to ride at the prestigious Prix de l’Arc de Triomphe over the weekend.
During the meeting in his native France, Soumillon rode one of the Aga Khan's horses to win the Group 2 Qatar Prix Daniel Wildenstein. Erevann's success on Saturday was followed by Vadeni's second for the owner in the big race, the Arc, on the following day.
The statement released by the Aga Khan Studs said: "Following last Friday's incident at Saint-Cloud, which resulted in the fall of Rossa Ryan, the Aga Khan Studs have taken the decision to cease their retainer with jockey Christophe Soumillon with immediate effect.
"From this week onwards, Soumillon may still ride in the Aga Khan silks on occasion at the discretion of the French trainers and the Aga Khan Studs team.
"At this stage, there is no intention to retain a jockey in France for the foreseeable future."
Soumillon had apologised for the incident and said he had not intended to make Ryan fall.
The Frenchman was appointed the Aga Khan's retained rider in 2014, following a previous run in the well-known green silks from 2002 to 2009.
The Aga Khan's daughter Princess Zahra Aga Khan had previously called the incident "an unconscionable, unthinkable thing to happen."
She said the team had planned to hold talks with the jockey on Monday,
"It was a very difficult thing to watch and it's very lucky that nobody got hurt," she added.
France Galop, the sport's governing body, pledged to revisit the rules to allow future bans to kick in immediately.
Chief executive Olivier Delloye said: "We cannot be happy about what happened and we are not happy about the bad publicity it has brought to racing but we can only work with the existing rules.
"We cannot invent new rules overnight, even following a bad situation as the one we saw on Friday."
As a result of the ban, Soumillon will miss major fixtures including British Champions Day at Ascot, the Breeders' Cup in America and the Japan Cup.
