Although the Shepard Fairey exhibit at The Andy Warhol Museum closed in January, the large murals Mr. Fairey and his crew put up way back in August have kept splashes of vivid color on Pittsburgh streetscapes through a long, dreary winter.

There were 20 such sites, pre-arranged by the Warhol, where posters by the acclaimed "street artist" were extensions of his "Supply & Demand" exhibit.

But supply apparently outstripped demand: Some local property owners discovered Fairey posters on their buildings without their permission, and they're none too happy about it.

"We were very upset," said Bruce Klein, owner of the North Side's Hartman building. "We didn't authorize it, and we couldn't get it off."

In a nice, wry twist, Mr. Klein is no stranger to the Pittsburgh art world. He owns the Photo Antiquities Museum and co-owns the Fein Art Gallery, both on East Ohio Street.

Several blocks away, however, the brick Hartman building is the last thing people see as they exit the North Side onto Interstate 279. Its cement block addition got tagged with Mr. Fairey's "Obey" eyeball image, its red and black graphics reminiscent of old Soviet propaganda.

"I had a guy out there for an hour and a half trying to remove it" -- to little avail, Mr. Klein said. "I'm trying to get investors interested in my property, and that's defacing it. It looks terrible."

Apparently one man's art is another man's eyesore. Ditto on the other side of the highway, where thousands enter the North Side or pass by on their way to the Strip District and Route 28. There, a long-closed gas station bears the black-and-white "Andre the Giant" face that first brought Mr. Fairey success 20 years ago.

"Some idiot put that up" last fall, said owner Shelby Greer when I called to ask about it.

But when I explained the poster was somehow connected to a museum exhibit, Mr. Greer exclaimed, "That's shocking! They had no permission to do that! It's hideous! I'm appalled that the Warhol would do this."

But who really did it is a bit of a mystery.

Derek Palladino, the Warhol's visitor services manager, said that although a curator arranged murals around town as "part of the package of a Shepard Fairey exhibit ... there are a lot of them non-approved by us."

So who did those?

"There's kind of a weird area with that," Mr. Palladino said. "It could have been copycats. It could have been Mr. Fairey himself -- we don't know."

Copycats? "I don't think so," said Mr. Klein. "They all went up around the same time."

And they seem to be the same images as the approved murals. And Mr. Fairey has been arrested and jailed for similar actions 15 times.

The artist, who was sued by The Associated Press for using its photo to produce his iconic "Hope" poster for the Obama campaign, recently said, "I want to get people's attention and make them question what they're seeing."

His posters certainly got people's attention on the North Side. As a community council member, I've fielded complaints about those "non-approved" posters. It seems context matters as much as content.

On occupied buildings in vibrant places like East Carson Street, the Fairey murals lend a rather festive feel -- if you're into the Castro's Havana kind of aesthetic. But on vacant buildings, "Obey Giant" -- the menacing Andre visage -- increases the dilapidated air that our community is struggling so hard to overcome.

Mr. Fairey hopes his images have "encouraged people to think, to look further into the content." If they do, they will find an intellectual mess.

He claims anti-authoritarian inspiration from George Orwell, but he romanticizes the Marxist revolutionaries who crush dissent. He parodies American icons like Uncle Sam ("Uncle Scam") as profiteering warmongers. He trashes private property rights to celebrate his own free speech. And doing so has made him a very successful capitalist.

Of his continued tagging of public spaces, he says, "It's never been about legal versus illegal." Tell that to people stuck with the costs of removing the posters.

At the Warhol, "there was talk of going around and removing some of them, once the weather warms up," said Mr. Palladino.

Most would welcome this good-neighbor gesture -- except for Lamar Advertising. The company supports murals all over town -- next up is a Romare Bearden tribute in Larimer -- but when one of Lamar's Route 65 billboards acquired an Andre face last fall, real estate manager Jim Vlasach had the image removed.

Someone put it right back up again, he said, and once he traced it to the Fairey exhibit, he decided to "let it go."

The structure is "getting replaced soon because of safety reasons -- you'd have to be completely crazy to climb up there," he warned. "We were just trying to clear up the graffiti.

"Or whatever you want to call it."

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