He built the Museum of Failure into a success. Now he wants it to flop.

Samuel West is begging people not to buy tickets to the internationally acclaimed show, and he isn’t joking.

West says his business partner, Martin Biallas, stole his collection and is opening the traveling exhibition without his permission. Biallas says the show is his and he has hired lawyers to shut down West’s campaign to keep people away.

A once-fruitful partnership has devolved into a bitter public feud full of name-calling and threats. Biallas has characterized West’s attempt at being an entrepreneur as an insult to failures. West called Biallas the “Donald Trump of the tacky art world."

“So somebody steals your car…and then he’s going to put it in a race, do I want that to succeed?" said West. “Nooooooooo."

Samuel West said he hatched the idea for the museum about a decade ago.

The traveling museum has drawn crowds around the globe for its collection of failed innovations. Highlights include Microsoft’s Zune and Colgate beef lasagna, the toothpaste maker’s attempt to sell frozen dinners. There’s also an adults-only section that features a spray-on condom that turned off testers because it took too long to dry.

It is often said that failure is an orphan, but the Museum of Failure has had several fathers.

West, a 51-year-old organizational psychologist, said he conceived the idea about a decade ago when he became fascinated by how fear of failure in the workplace stifled innovation. A museum, West said, was an “exciting and fun way to communicate the ideas of destigmatizing failure and accepting it."

When it opened in 2017 in a gallery in Sweden, where West was living, the small exhibition of items that he’d procured from eBay and elsewhere was a surprise hit, drawing huge crowds and international attention.

“What do coffee-flavored Coca-Cola, a Donald Trump board game and a 1940s lobotomy tool have in common? They are all considered innovation flops," CNN reported at the time.

Visitors look at items on display at an exhibition in Sweden in 2019, including a Segway scooter, a plastic bicycle and a Sinclair C5 electric vehicle.

But within two years, West was locked in a legal battle with two business partners over ownership of the museum. When he couldn’t pay the legal fees, he was declared bankrupt in Sweden.

After studying and talking about failure for years, West recalled the personal sting and shame of his own. He reminded himself of a quote he’d often shared with others from Jon Sinclair: “Failure is a bruise, not a tattoo."

“I know it’s true," he said. “But also when it hits me in the face, it hurts."

The partnership with Biallas began with great promise. Biallas, 65, is known for traveling exhibitions like the life-size reproductions of Michelangelo’s Sistine Chapel—an idea he had after visiting the real one in Vatican City.

“They push you in there…there’s 2,000 screaming people, no atmosphere, they push you out after 15 minutes, you can’t take photos," he said.

Biallas has done other exhibitions on the Smurfs and Hot Wheels. He ran into trouble for one called the “Louvre Fantastique" when the actual Louvre in Paris sued his company for trademark infringement, an issue that Biallas blamed on his attorney.

Martin Biallas was known for traveling exhibitions like the life-size reproductions of Michelangelo’s Sistine Chapel.

When Biallas read about the Museum of Failure, he flew to Sweden to make his pitch. West cleaned his old Alfa Romeo and picked him up at the airport. He was impressed by his new friend, who told stories of partying with David Bowie.

They went into business. Biallas’ company got a license to operate a traveling exhibition of the museum outside of Sweden. He would be responsible for finding gallery space, setting up the shows, advertising and ticket sales. West would provide the collections and make appearances at openings.

Together, they created big shows in major cities like New York, Los Angeles and Shanghai.

But in recent years, the pair squabbled over money. In 2023, West alleged he wasn’t being paid his 20% cut; Biallas’ lawyers fired back that West had agreed to receive his commissions after Biallas’ company recouped its $240,000 investment from a show in Minneapolis. West said he asked for his collection back.

The feud exploded when West said he found out that Biallas was opening a show in San Francisco by reading about it in the news. With its proximity to Silicon Valley, the capital of failing forward, West said it felt like a slap in the face. He posted a message on the museum’s website telling people to stay away.

The Rejuvenique facial mask is displayed during a preview at the Museum of Failure in Washington, D.C. in 2023.The Trump board game on display at an exhibition in Sweden in 2019.

Biallas says West’s allegations are baseless because he owns the museum trademarks and has the rights to the collection. He doesn’t need West’s permission to open a show, he said.

Biallas’ lawyers in recent weeks hit West with a barrage of legal papers ordering him to hand over the website. West has since taken down the message on the site.

“I’m going to open this thing without him and I’m going to shut him down," Biallas vowed.

The opening date has been pushed back to early April because of the conflict.

Biallas said he wasn’t offended by the comparison to the president: “In today’s political world, I would say it’s a compliment." He, in turn, chided West as a “failed entrepreneur," though he said that such a failure doesn’t deserve a place in the show.

“Out of respect to everyone, I wouldn’t want to put him in the museum," said Biallas. “But we do have Donald Trump in there."

Trump steaks, Trump University and the Trump board game are all featured in the exhibition.

Biallas said he’s drawn his own lessons from the debacle: “I learned to move on," he said. “All the background circus is going to be dealt with in the courts."

West said he’s learned that he was too naive from the outset.

“I wouldn’t be as trusting," he reflected. “I would not clean the Alfa Romeo for him again."

Write to Zusha Elinson at zusha.elinson@wsj.com