A former professional baseball player who was once the largest black McDonald's operator in the US has sued the company for racial discrimination.
Herb Washington said the firm had denied black owners the opportunities it gave to whites, including by steering them to stores to "distressed, predominantly black" areas.
He accused the company of retaliating against him after he raised concerns.
McDonald's blamed his troubles on "mismanagement".
In a statement, the firm said it was reviewing the complaint, adding that Mr Washington was facing "business challenges that we don't want for anyone in our system."
"This situation is the result of years of mismanagement by Mr Washington, whose organisation has failed to meet many of our standards on people, operations, guest satisfaction and reinvestment," the company said.
"His restaurants have a public record of these issues, including past health and sanitation concerns, and some of the highest volumes of customer complaints in the country."
McDonald's has faced similar claims from black franchise owners before. In a lawsuit last year, more than 50 former franchise owners accused the company of steering them to stores in less desirable neighbourhoods.
Mr Washington, who opened his first McDonald's franchise in 1980 at the age of 29 after a brief stint playing for the Oakland Athletics, said the firm had repeatedly hindered his business.
That included by blocking him from buying stores from a white franchise owner and denying him financial assistance comparable to that offered to white operators.
Despite the challenges, Mr Washington said he at one point ranked as the company's largest black operator in the US, with 27 restaurants. He continues to own 14 stores.
"I always held out hope that they would live up to their promises and put an end to a two-tiered system," he said at a press conference announcing the lawsuit, which was filed in federal court in Ohio. "I believed that McDonald's was going to do the right thing."
Since 2017, he said the company had targeted him for "extinction" in retaliation for his speaking up about racial disparities, pushing him to sell certain stores in exchange for contract extensions on others.
At the press conference, he rejected the firm's characterisation of his business, saying that McDonald's wouldn't have allowed him to be a franchisee for 40 years if he were consistently "bringing down the brand".
"When I stood up for myself and other black franchisees, McDonald's began to dismantle my life's work," he said. "I didn't quit on McDonald's. McDonald's quit on me."
'Racist policies and practices'
In his lawsuit, Mr Washington said the company's discriminatory policies worsened after British-born Steve Easterbrook took over in 2015.
Mr Easterbrook was fired from the company in 2019 for having a consensual relationship with a subordinate in violation of the firm's policies.
During his tenure, the company implemented remodelling initiatives that were "designed to force black franchisees out of the McDonald's system," the lawsuit says.
The number of black McDonald's franchisees in the US has dropped from 377 to 186 since 1998, the lawsuit says. It also says black-owned restaurants average $700,000 less in sales annually than white-owned ones.
"These numbers are not a coincidence; they are the result of McDonald's intentionally racist policies and practices toward black franchisees," the lawsuit says.
McDonald's, which announced a diversity initiative in July amid the Black Lives Matter protests, said performance at black-owned restaurants had improved and it did not place franchisees in specific locations, but made recommendations.
It added that the company had taken steps to reduce the number of overall number of operators across all demographic groups as part of a restructuring initiative. Nearly 30% of its franchises are "ethnically diverse", it said.