A federal judge on Wednesday backed an initial legal challenge to the Federal Trade Commission’s ban on noncompete agreements, which is scheduled to take effect in September.

Judge Ada Brown granted an injunction requested by several plaintiffs, saying the ban cannot be enforced against them pending a final ruling.

But while the ruling is preliminary, she said that the F.T.C. lacked “substantive rule-making authority” with respect to unfair methods of competition and that the plaintiffs were “likely to succeed on the merits” of their challenge.

Judge Brown, of U.S. District Court for the Northern District of Texas, said she expected to issue a final decision by the end of August.

The commission “stands by our clear authority, supported by statute and precedent, to issue this rule,” said Douglas Farrar, an F.T.C. spokesman. He added that the agency would “keep fighting” noncompetes in an effort to promote worker mobility and economic growth.

In April, the tax firm Ryan L.L.C. sued to block the near-total ban on noncompetes, just hours after the F.T.C. voted 3 to 2 to adopt the rule. The U.S. Chamber of Commerce later joined the case as a plaintiff, as did the Business Roundtable and two Texas business groups.

Banning noncompete agreements, which prohibit workers from switching jobs within an industry, would increase workers’ earnings by at least $400 billion over the next decade, the F.T.C. estimates. The agreements affect roughly one in five American workers, or around 30 million people, according to the agency, whose purview includes antitrust and consumer protection issues.

“If you’re not working in the most productive place you could be working because of a noncompete, that’s a loss for the economy,” Aviv Nevo, director of the F.T.C.’s Bureau of Economics, said at a conference in April.

Business groups argue that the ban would limit their ability to protect trade secrets and confidential information. The Chamber of Commerce and other groups assert that the F.T.C. lacks constitutional and statutory authority to adopt its proposed rule, with Ryan L.L.C. calling it “arbitrary, capricious, and otherwise unlawful.” Another lawsuit seeking to block the rule is pending in federal court in Pennsylvania.

But the three Democrats on the five-member commission maintain that it can legally issue rules defining unfair methods of competition under the F.T.C. Act of 1914, the law that created the agency. Their position has garnered some bipartisan support, too: Representative Matt Gaetz, Republican of Florida, argued in a brief filed in the Texas case that the noncompete ban falls “squarely within” the rule-making authority granted to the commission by Congress.

The Supreme Court’s decision last week to limit the broad regulatory power of federal agencies could raise the agency’s legal hurdles.

Mark Goldstein, a labor and employment lawyer at Reed Smith in New York, said that while limited to only the plaintiffs at this stage, Judge Brown’s injunction was a strong indication that she would deem the F.T.C.’s rule invalid, preventing it from going into effect nationwide.

“The writing is on the wall there,” Mr. Goldstein said. “I have never seen a court issue a preliminary injunction and then, absent some extremely unusual circumstances, issue a final decision that wasn’t consistent with the preliminary injunction.”

As litigation over the noncompete rule drags on, some lawyers are already advising employers to start relying more heavily on different agreements to protect trade secrets and business interests.

In a blog post after the F.T.C. adopted its noncompete ban, the law firm Winston & Strawn suggested that employers adopt alternative measures, such as narrowly tailored nondisclosure agreements and requirements that employees repay the company for training costs if they leave before a set period — known as training repayment agreement provisions, or TRAPs.

“Focus on these additional protections has become greater,” said Kevin Goldstein, an antitrust partner at Winston & Strawn.

But even those agreements are under increasing scrutiny. The commission’s final rule encompasses “de facto noncompetes” — measures that, in effect, prevent a worker from switching jobs within an industry, even if they aren’t labeled noncompete clauses. And employers are eyeing the shifting landscape of state and federal restrictions on such covenants, including nondisclosure agreements, beyond the F.T.C.’s rule.

While the commission’s vote to ban noncompetes has garnered the most attention, moves from other federal agencies and state legislatures against agreements that restrict worker mobility are simultaneously on the rise.

“There’s been increased hostility toward these agreements in general, across the country,” said Christine Bestor Townsend, co-chair of the unfair competition and trade secrets practice group at Ogletree Deakins.

Last month, a National Labor Relations Board judge ruled for the first time that a noncompete clause is an unfair labor practice, as part of her decision in an unfair-termination case. The judge also broke new ground by barring a nonsolicitation clause, which restricts soliciting clients or employees of a former employer; she argued that both types of agreements could chill protected activity, including union organizing.

That ruling followed a memo last year from the labor board’s general counsel, Jennifer Abruzzo, that clarified her view that noncompete provisions in employment contracts violate the National Labor Relations Act, except in limited circumstances.

“It’s one thing to get a guidance memo from the general counsel, which is significant and important,” said Jonathan F. Harris, an associate professor at Loyola Law School in Los Angeles who studies contracts and employment law. “And it’s another thing to see the adjudication side of the N.L.R.B. agree with her.”

These kinds of restrictive covenants tend to scare workers away from labor organizing, Mr. Harris said, “because the consequences of being fired for organizing become that much greater if you can’t get another job afterwards.”

Other federal agencies have jumped in as well, eyeing a range of employment provisions that they argue unfairly constrain workers. It’s part of the whole-of-government approach by the Biden administration to what it considers anticompetitive restraints on worker mobility.

The Consumer Financial Protection Bureau, for example, issued a report last summer on the dangers of provisions requiring workers to repay training costs if they leave a job before a certain time elapses.

It’s not just a federal push: State governments are also stepping in to promote worker mobility — a trend that was in motion before the F.T.C. voted to ban noncompetes in April, but one that has gained momentum since.

Last month, the Rhode Island legislature passed a bill to ban noncompetes, joining Minnesota, California, Oklahoma and North Dakota. Dozens more states have enacted partial restrictions.

“Minnesota didn’t turn into a gaping crater,” said Pat Garofalo, the director of state and local policy at the American Economic Liberties Project, a progressive think tank, referring to the state’s wide-reaching ban on noncompetes that went into effect last year. “Once a domino falls over, a bunch of other dominoes fall over after.”

State laws can also prove more resilient to challenges than federal rules.

“State legislatures obviously have a lot of interest in getting these rules on the books right now,” Mr. Garofalo said.

In the spring of 2021, Chet Hanks, the singer, actor and son of Tom, posted a series of statements and a music video with a refrain that caused confusion, not to mention a fair bit of cringing. He declared it was going to be a “white boy summer.”

Whatever exactly he meant at the time, the phrase has since mutated into a slogan for white supremacists and other hate groups, according to a report published on Tuesday by the Global Project Against Hate and Extremism, an organization that tracks the spread of racism.

Thousands of posts using the slogan “white boy summer” have appeared on the Telegram app alone this year. It’s been used by far-right groups to recruit new followers, organize protests and encourage violence, especially against immigrants and L.G.B.T.Q. people, the report said.

For many of those who use it now, the phrase represents an unapologetic embrace of white heterosexual masculinity, often at the expense of women and people of color.

Increasingly, the meme has moved from the fringes of the internet into the political mainstream in the United States and elsewhere around the world, one of the group’s founders, Wendy Via, said.

Jack Posobiec, a podcaster whom the Southern Poverty Law Center has linked to white supremacists, waved a banner with the words “white boy summer” on it at a gathering for Turning Point USA, a conservative group, in Detroit last month. Former President Donald J. Trump was the conference’s keynote speaker, along with several members of Congress.

“It’s really about how quickly and how devastatingly something like this can go viral and the impact it has,” Ms. Via said of the phrase that Mr. Hanks coined. Extremists, she added, “are hurting people all over the world in the name of this thing.”

Mr. Hanks, 33, did not respond to numerous requests for comment through his social media accounts and the talent agency that represents him, but after this article appeared he posted a statement on Instagram condemning use of the phrase in any bigoted way.

“White boy summer was created to be fun, playful, and a celebration of fly white boys who love beautiful queens of every race,” he wrote. “Anything else that it has been twisted into to support any kind of hate or bigotry against any group of people is deplorable and I condemn it.”

Mr. Hanks started using the phrase in a series of posts on social media in 2021 about fashion and other advice for men. He seemed to anticipate that the meaning of the words required some explanation.

“Take it how you want it,” he said in a post on Instagram that March. “I’m not talking about, like, Trump, NASCAR-type white,” he went on, saying he meant people like himself and two other white R&B artists, Jon B. and Jack Harlow. “Let me know if you guys can vibe with that. And get ready, ‘cuz I am.”

His music video — produced under the name Chet Hanx — appeared the month after. It was a homage of a sort to the hit two years earlier by Megan Thee Stallion, “Hot Girl Summer,” featuring Nicki Minaj and Ty Dolla $ign.

It is replete with profanity, as well as sexist and racial slurs, but it also ends with an image of Mr. Hanks wearing a shirt with the words “stop hate” on it.

“White boy summer” is not the first artistic creation that white supremacists have hijacked and used online in hate speech.

Pepe the Frog, a comic book character created by Matt Furie, became so popular in racist, antisemitic and homophobic memes that the Anti-Defamation League classified it as a hate symbol in 2016. Mr. Furie killed off the character a year later, but it still circulates in ways he never intended.

Even before the meme, Mr. Hanks faced criticism for using — and defending the use of — a racial slur against Black people. He has also been accused of cultural appropriation after he started using, as an affectation, Jamaican patois in public appearances, including at the 2020 Golden Globe Awards, where Tom Hanks received the Cecil B. DeMille Award.

As a meme and a hashtag, “white boy summer” has with each passing summer been embraced by groups like the Proud Boys and “active clubs,” groups that blend racist ideologies with martial arts and other activities.

While more prevalent on fringe sites populated by extremist content, including Gab, Rumble and 4chan, the phrase also appears regularly on X, Instagram, Facebook and other major social media platforms, often with Nazi images. The phrase and its various hashtags appear to skirt policies that prohibit hate speech in part because it is often used euphemistically or ironically.

“While this trend/meme originated on the far right, it is definitely creeping into more ‘mainstream’ right-wing discourse,” said Todd Gutnick, a spokesman for the Anti-Defamation League, which documented the slogan’s spread early on.

The Global Project Against Hate and Extremism report noted that the meme was now being used by extremist groups in countries around the world.

A group in France created stickers with the phrase — in English — for members to distribute, while another in Finland held an annual festival last month using the phrase as its name. Writing about last year’s event, Bellingcat, a research organization, reported that attendees “watched far-right bands perform, participated in combat sports and mingled with other hate group members in hot tubs.”

“The far right is adept at bringing their hateful ideologies into the mainstream, especially through the use of social media,” the report said, “and the already-viral ‘white boy summer’ has proved to be the perfect segue from them to spread their bigotry to a wider audience.”

Mr. Hanks, who also previously performed as Chet Haze, has had much-publicized struggles with drugs and accusations of domestic abuse that have contributed to his rebellious persona as a performer. “He’s a grown man,” his older half brother, Colin, who is also an actor, said in a radio interview in 2016, when asked if he had ever intervened with advice. “He’s going to do what he wants to do.”

Tom Hanks does not appear to have commented publicly on his relationship with Chet Hanks, though the son recently posted a cross-generational exchange of text messages with him about the recent feud between the rappers Drake and Kendrick Lamar. In an interview with The New York Times in 2019, the father described his experience as a parent.

“Somewhere along the line, I figured out, the only thing really, I think, eventually a parent can do is say: ‘I love you, there’s nothing you can do wrong, you cannot hurt my feelings, I hope you will forgive me on occasion, and what do you need me to do?’” he said.

Despite the controversy over its spread, Mr. Hanks continues to embrace the meme. “I have consulted with the heavens, felt a westward breeze, and walked outside of a strip club and saw my shadow …,” he wrote on Instagram in May. “This will be a #WBS.” He ended the post with the emoji of a church.