Twitter users on Thursday saw the verified blue check marks disappear from certain accounts.

Verified accounts that did not sign up for the social media platform’s subscription service lost their blue check marks.

The subscription service is called Twitter Blue; the starting costs are $8 per month or $84 per year, but the costs are higher if the subscriber uses Twitter on iOS.

The subscription allows users to edit tweets, write longer tweets, view fewer ads, and bold and italicize text. It also functions as a form of verification.

The company will denote verified business organizations with a gold check mark and government agencies with a gray check mark, according to CNN.

CNN reported that the likes of Kim Kardashian, Beyonce, Bill Gates, Pope Francis, Donald Trump, and U.S. Citizenship and Immigration Services all lost their check marks.

Recently, the hashtag #BlockTheBlue took off on Twitter, with users lobbying to block blue check-marked accounts in protest of the app introducing the subscription service.

Mia Farrow, actress and activist, who did not have a verified Twitter Blue check mark, tweeted, “You’ve ruined twitter Elon. It’s an ad riddled indecipherable mess.”

Additionally, some accounts have reported having the verified blue check mark despite not paying for the subscription service, leading to speculation that some high-profile organizations or celebrities were given the check mark to minimize the backlash against it.

The Massachusetts Institute of Technology has a blue check mark, but the organization tweeted that “we did not subscribe to Twitter Blue.”

Bret Weinstein, an author and podcaster, spoke out in favor of Twitter Blue, tweeting, “Let’s face it. #BlockTheBlue is a rebellion against an honest buisness [sic] model for Twitter in favor of an opaque one that delivered us, not only to advertisers, but to a powerful corporate-government hybrid that censored and manipulated us into massive self-harm.”

Elon Musk defended his choice by tweeting that “it’s more about treating everyone equally. There shouldn’t be a different standard for celebrities imo.”