LONDON — Just after 11 a.m. on Thursday, a group of about 20 artists, many wearing black despite the searing sun, arrived at the Design Museum in London with an unusual aim: to remove their art from an exhibition.
Their works appeared in “Hope to Nope: Graphics and Politics 2008-18,” a show that traces the recent history of activist art and design, starting with Shepard Fairey’s “Hope” poster from Barack Obama’s first presidential election campaign, through to a “Make America Great Again” baseball cap.
The artists were upset that the Design Museum had rented its atrium to Leonardo, one of the world’s largest aerospace and defense companies, for a drinks reception in July. Many of the artists in “Hope to Nope,” including Mr. Fairey and Milton Glaser, the designer behind the “I ♥ NY” logo, expressed shock when they learned about the reception, and asked for their works to be removed from the museum. On Thursday, the group arrived to check that this had happened, or to do it themselves if necessary.
Charlie Waterhouse, creative director of This Ain’t Rock ’n’ Roll, a design agency with work in the show, said, “It’s a quite wonderful irony that’s its blown up with an exhibition like this.” The museum had criticized the activists for making a fuss, he added. “That’s also ironic,” he said, “criticizing us for being the very thing we were only a minute ago being celebrated for.”
When the artists entered the museum, their works were already neatly packed and waiting for them. They spent several minutes unwrapping them to hold them up for waiting photographers.
The museum said it had removed 29 works, a third of those on display. They were replaced with signs reading, “This artwork was removed at the request of the lender who has objected to a private event by an aerospace and defense company that was held at the Design Museum.”
Cultural institutions are regularly the target of protests in Britain if they accept sponsorship or funding from companies seen as unethical. Tate and the British Museum have been targeted for exhibitions sponsored by the oil company BP. In March, the defense contractor BAE Systems withdrew its sponsorship from an arts festival, the Great Exhibition of the North, after several musicians pulled out. In the United States, protests have been seen recently at museums that have taken money from the Sackler family, who protesters link to the opioid crisis.
But it is rare for artists to withdraw their work from an exhibition. “I’ve been working in the sector for 20 years and I’ve never had this happen to me,” Alice Black, one of the Design Museum’s directors, said in a telephone interview.
The “Hope to Nope” exhibition had been a critical and commercial success since opening in March, with more than 30,000 visitors. If news of the Leonardo drinks reception had not appeared on Twitter, it would probably have continued to flourish until it closed on Aug. 12.
The protest was coordinated by Jess Worth, co-founder of BP or Not BP?, an activist group set up to target cultural events that receive sponsorship from the oil company. Members of her group had work in the exhibition, and she said she had been shocked when she learned about the reception. “I was absolutely horrified, because it feels very personal when it’s your work on display,” she said.
Ms. Worth first asked the museum to apologize and to promise not to hold events by “unethical” firms, then requested the work to be removed when the museum did not meet the demands in full.
In an open letter on its website, the museum said that it would review its policy on who could rent its spaces, but added, “we are in the midst of an argument not of our making.”
“We will not be seen as an easy target and a surrogate for the real target of these campaigners,” the letter added. “We do not want our programs to be co-opted by the agenda of others, and we stand by our curatorial independence.”
The letter did not ease tensions. Mr. Fairey, in an emailed statement, said that he understood the museum’s need to make money. But that did not mean it should work with a defense firm, he added. “I’ve had to make hard choices in my past,” he said, “but it’s always been important for me to put my belief system first and my financial needs second.” Mr. Fairey once turned down a commission from the cigarette firm Marlboro, his spokeswoman said in a telephone interview.
Ms. Black, the museum director, stressed that holding the reception did not mean that the museum endorsed Leonardo’s business. “This is how we exist,” she said, pointing out that the museum only got 2 percent of its funding from the government. “It’s not easy in the current context to continue to operate.”
“I am saddened by the whole situation,” she added, saying that she was concerned about what the episode could mean for future exhibitions looking to cover activist art.
At the museum on Thursday, Ms. Worth said that the artists’ actions could be “a turning point for the ethical funding in the cultural sector. If you don’t do your due diligence on the money you take, it can have serious consequences.”
The protest had also brought the artists together, she added, as they gathered with their recovered art on the street outside, prompting bemused looks from passers-by.
Some of the artists were planning an exhibition to show the removed work, Ms. Worth said.
“Maybe that isn’t what the Design Museum wants to hear,” she added, “but there is something good that’s come out of this.”