Bill O’Reilly is losing his crown as the king of cable TV, and a grassroots social media-based movement may have played a major role in dethroning him.

Amid a flurry of sexual assault allegations against him, with another woman on Tuesday coming out with accusations, O’Reilly, who is on vacation, will not return to his namesake show at Fox’s “The O’Reilly Factor.”

Fox News parent company 21st Century Fox (FOXA) issued a statement on Wednesday afternoon:“After a thorough and careful review of the allegations, the Company and Bill O’Reilly have agreed that Bill O’Reilly will not be returning to the Fox News Channel.”

The cable host’s ouster comes after a grassroots Twitter group called Sleeping Giants urged companies to pull their ads from the show. According to Sleeping Giants and Media Matters, 83 companies have pulled their ads from “The O’Reilly Factor” and just 49 are still pushing their ads on the show.

Sleeping Giants doesn’t have a website and operates solely on Twitter and Facebook, where it rallies people to tweet at and message individual brands that have advertised on questionable websites. The group, whose founders are anonymous, consists mostly of people in the marketing industry.

“We decided to get involved because there’s no larger, all-encompassing example of bigotry than sexual harassment at the workplace,” a Sleeping Giants co-founder told Yahoo Finance. “[Bill O’Reilly] has definitely proven to be bigoted in the past so it made sense for us to jump in.”

‘A brutal campaign of character assassination’

On Tuesday afternoon, an attorney for O’Reilly released a statement saying “Bill O’Reilly has been subjected to a brutal campaign of character assassination that is unprecedented in post-McCarthyist America.” That statement went on to say O’Reilly was a victim of a “smear campaign … being orchestrated by far-left organizations bent on destroying O’Reilly for political and financial reasons. That evidence will be put forth shortly and it is irrefutable.”

One of these so-called “far-left organizations” the lawyer is undoubtedly referencing is Sleeping Giants, which cropped up the day after the presidential election with the mission “to stop racist and sexist media by stopping its ad dollars.”

Originally targeting Breitbart, Sleeping Giants says it helped push 1,915 companies to stop advertising on the site. Since the Breitbart campaign, Sleeping Giants has been focused on getting companies to stop advertising on “The O’Reilly Factor.” Many of those companies don’t even realize that their ads are being aired because of programmatic buying.

“We contemplated whether or not we would focus on O’Reilly because we wanted to make sure it was on message and for what we had been doing. A lot of the community we had built was clamoring for us to do it,” a Sleeping Giants co-founder told Yahoo Finance.

The group of co-founders have kept their identities anonymous. Even in organizing an interview with Yahoo Finance, Sleeping Giants used a generic e-mail address and called from a blocked phone number.

“We want it to be about the mission”

Marketing professionals by day, the group’s organizers said they didn’t want their names attached to Sleeping Giants because of professional conflicts of interest.

Plus, as passionate as they are about the mission, the co-founder said attaching his name to the organization could “get in the way of our lives.”

“We want it to be about the mission, not us. In a way, we can stop going tomorrow and the community will continue running it,” he said.

Though Sleeping Giants emphasizes that it’s ethically-motivated, its campaigning has serious monetary consequences.

O’Reilly’s show, for example, is the most popular cable news show on television and its top revenue producer. The show brought in over $178 million in ad dollars in 2015 and $118.6 million in the first nine months of 2016, according to Kantar Media. The campaign could have seriously damaged a media favorite of conservatives if it had continued.

Despite Sleeping Giants’ acknowledgement that the vast majority of its 85,000 Twitter followers are Democrats, the co-founder insisted that it’s not a political campaign.

“People are engaged and looking for ways to get involved. Bigotry is something that we feel is a non-partisan issue,” he said. “It’s always been more about providing information rather than boycotting. We want to keep the conversations positive and support brands that are doing the right thing.”

Melody Hahm is a writer at Yahoo Finance, covering entrepreneurship, technology and real estate. Follow her on Twitter @melodyhahm.

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