Banksy Is a Control Freak. But He Can’t Control His Legacy.

The contrast between the 17th-century old master and 21st-century disrupter couldn’t have been more extreme.

To the left, Rembrandt’s broodingly introspective “Self-Portrait With a Red Beret.” To the right, behind a protective glass screen, Banksy’s “Girl With Balloon,” the painting that had made global headlines when it sensationally self-destructed at an auction. Its frayed canvas now dangles limply below its elaborate gold frame.

Retitled “Love Is in the Bin,” the end result of what many regard as the most spectacular of all Banksy stunts has just spent almost a year on loan at the Staatsgalerie Stuttgart in Germany.

The damaged exhibit freeze-frames the moment at the end of a 2018 contemporary art auction when, to loud gasps, a painting that had just sold for $1.4 million slid through a remotely controlled shredding mechanism, then jammed halfway. Sotheby’s had been “Banksy-ed.” Paradoxically, market experts regard the work as even more valuable now that it commemorates a famous Banksy stunt designed to expose the excesses of the art trade.

The exhibition of the work, on loan from its anonymous German buyer, finished last Sunday, transforming attendance figures at this normally straight-faced German museum. During those 11 months the Staatsgalerie attracted 180,000 visitors, about double the usual, according to Charlotte Mischler, the museum’s head of communications. It stayed open until 10 p.m. for the last five days to cope with demand.

This is quite a turnaround. Fifteen years ago Banksy, a young upstart street artist from Bristol, England, was smuggling his works into museums as pranks. Now, they can be the official stars of the show, accompanied by guided tours and lectures.

How has Banksy, the archetypical artist-provocateur, gotten here? None of it has happened by accident. Banksy’s rise and rise is the result of years of meticulous control of his message, his market and, most importantly, his mystique.

The enormous popularity of Banksy’s brand of urban art has given the cultural establishment, increasingly jittery about perceptions of elitism, plenty to think about. The Staatsgalerie Stuttgart has asked the question: Is Banksy a historically significant artist? If he is — and for many that is a very big “if” — what will be his legacy?

Joining the artistic pantheon would have been the last thing on Banksy’s mind in the early 2000s when he was a young, carefree tagger spray painting images of rats, chimpanzees, rocket-launching Mona Lisas and kissing policemen on the streets of Bristol and London.

Steve Lazarides was the artist’s agent, photographer and collaborator during those formative years and went on to set up a commercial gallery in London, which represented Banksy from 2006 to 2008. In a recent interview, he said the artist was “a total control freak, down to every last detail,” adding, “That’s what makes him so good.” In December, Mr. Lazarides published “Banksy Captured,” a book chronicling those glory years when the artist produced his most celebrated street pieces.

But Mr. Lazarides fell out with Banksy in 2008 and withdrew from the commercial gallery scene last year. “The internet has made it redundant,” he said. “Why give the dealer 50 percent? Thanks to artists’ own websites and Instagram, the artist can sell directly to collectors and keep all the money.”

Banksy now has no gallery representing him, but discreet multimillion-dollar sales of original works to selected private collectors have helped fund his ongoing graffiti stunts and ambitious larger-scale projects, like “Dismaland,” a pop-up amusement park in southern England, and the Walled Off Hotel, an exhibition space, spray paint store and nine-room lodging in Bethlehem on the West Bank.

Banksy has also gone to great lengths to regulate the resale trade in his output. In 2008 he set up Pest Control, an agency to authenticate works and prevent fakes and site-specific street pieces from appearing on the market. Reputable dealers and auction houses now sell Banksy works only with Pest Control certification.

The “hidden hand” of Banksy can also exert an influence on auctions. Though Banksy himself gets little direct benefit from these public sales, the results underpin the prices he can charge to his private collectors.

In October, when Britain’s politicians were still deadlocked over Brexit, many people suspected Banksy played a role in the timely auction of his 2009 painting, “Devolved Parliament.” Offered by an anonymous private collector, the monumental Victorian-style painting shows an animated debate in the British Parliament conducted entirely by chimpanzees.

Banksy’s team denied any involvement, but Sotheby’s didn’t take any chances: Nervous they might be “Banksy-ed” again, the auction house made attendees pass through a metal detector to enter the salesroom. The painting sold without incident for a record $12.1 million, beating the artist’s previous auction high by more than six times.

The London dealer Acoris Andipa, who specializes in Banksy’s works, noted that “Devolved Parliament” had been promoted on the artist’s Instagram account in March. “It seems inconceivable that a work would jump to that level without some kind of influence or involvement from the artist,” Mr. Andipa said.

Outside the auction rooms, Banksy uses nondisclosure agreements and trademark law to maintain his anonymity and the singularity of his creative vision. The fact that his identity has yet to be definitively revealed is a testament to his team’s corporate discipline.

“He gets everyone who works on projects like ‘Dismaland’ to sign N.D.A.s so that everything is kept confidential,” Enrico Bonadio, a senior lecturer in law at City University in London, said. “He employs a lot of lawyers.”

Recently, Banksy’s representatives have been using European Union trademark law to crack down on knockoff merchandising. The artist who once declared in one of his murals that “copyright is for losers,” and who grudgingly tolerated unauthorized exhibitions for years now seems to have had enough of others profiting from his work.

Copyright is the traditional way that artists protect their works from unauthorized reproduction; trademark law safeguards commercial logos. But, as Mr. Bonadio pointed out, “If you want to take a copyright action, you have to disclose your identity.” This was why Pest Control was now enforcing Banksy’s trademarks, he added.

Last January, in a preliminary ruling, an Italian judge upheld Pest Control’s claim that merchandise on offer at “A Visual Protest: The Art of Banksy,” a show that went ahead without Banksy’s blessing, infringed the artist’s trademark rights. Six items were removed from the gift shop.

Two months later, Full Colour Black, a British greetings card maker, began legal action to cancel a trademark registered by Pest Control to protect Banksy’s iconic “Flower Thrower,” showing a masked rioter about to hurl a floral bouquet.

Banksy was advised by his lawyers that the most effective response would be to create and market his own merchandise. This would show he was actively using his trademarks in a business, rather than just warding off appropriators.

The result was “Gross Domestic Product,” a short-lived online store of 22 items selling tongue-in-cheek homewares. The items, including a three-panel print based on “Flower Thrower,” were also available for view in a pop-up window display that suddenly appeared in a South London suburb in October, then disappeared two weeks later.

The legal effectiveness of Banksy’s strategy will be judged later this year with a ruling from the European Union’s trademark office. Full Colour Black’s attempt to cancel the artist’s trademark remains pending. In the meantime, the company continues to offer a wide range of Banksy-inspired cards (but not “Flower Thrower”), according to its website.

These strategies of remote control also extend to Banksy’s dealings with the news media, whose publicity oxygenates his fame and mystique, but whose enquiries can be an irritant.

The artist does not communicate directly with journalists, but only through a single press spokeswoman, Joanna Brooks, who declined to answer questions for this article. Ms. Brooks said that Banksy would respond if publication were delayed until March, when the artist would make a significant announcement.

Posts on Banksy’s Instagram account (7.1 million followers) are all the more impactful for being so occasional. A new painting is suddenly announced — like the Yuletide reindeer stenciled on a wall next to a homeless person in Birmingham, England, posted on Dec. 9 — and worldwide media coverage from the BBC, The Guardian, Reuters and other outlets duly follows, which is shared and commented on via social media.

This cycle of surprise announcements keeps Banksy in the public eye, but will it ever result in works hanging on the walls of the world’s most important museums? The loan show at the Staatsgalerie Stuttgart is one thing, but there are still no Banksys in the permanent collections of Tate Modern in London or the Museum of Modern Art in New York.

The curator and critic Francesco Bonami, who selected works for the 2010 Whitney Biennial, is not surprised. “Great artists, I believe, invent a language and a grammar,” he said. “Banksy did not.” He added that his signature stencil style, developed by the French graffiti artist Blek le Rat in the 1980s, had been around for “a long time.”

What Banksy does is more like an advertising campaign than art, Mr. Bonami added.

But rather than concentrate on individual images, which can have a throwaway quality, Banksy’s admirers see value in his role as an activist as much as in the art itself.

Mike Snelle, a.k.a. Brendan Connor of the Connor Brothers artist duo, said that Banksy’s crazily original projects, like “Dismaland” and “Gross Domestic Product” would ultimately define his legacy, rather than stenciled prints of “Flower Thrower.”

“I can’t think of another artist in terms of the scale of what he’s doing,” Mr. Snelle said. “Those projects cost a huge amount to fund. He’s more than happy to put his money where his mouth is when it comes to his beliefs.”

“Dismaland’s” website says that in 2015, after the so-called “bemusement park” had been dismantled, all the building materials were reused to construct shelters for homeless migrants near Calais, France. Similarly, Banksy said that proceeds from “Gross Domestic Product” would be put toward the purchase of a new migrant rescue boat in the Mediterranean.

“What’s more important?” Mr. Snelle asked. “Doing something that might save people’s actual lives, or something in some rarefied museum?”

John Zarobell, an associate professor at the University of San Francisco and the author of the 2017 book “Art and the Global Economy,” said in an email that he saw Banksy as “a conceptualist prankster, à la Duchamp, whose gestures may be more lasting than the work itself.”

“The art world is famously hot/cold about outsiders,” Mr. Zarobell said. “They generate a lot of energy, and bring a new audience into the fold of high culture, but they are interlopers and the test is whether they will survive the transition from street to gallery, now to auction house.”

The next big question — whether the artist likes it or not — is whether Banksy will eventually make the final transition to those rarefied museums.

Even Banksy can’t control that.