In an official partnership with the New York City Department of Transportation, Ryan McGinness has erected 50 signs throughout Manhattan. The red-and-black compositions are the approximate shape and material of a standard street sign, but feature abstract visual language intended to delight and inspire passers by.

Some people have been inspired differently than others. Since their arrival three weeks ago, as many as 40 of the signs have been stolen in a kind of highbrow street crime that has the artist and the DoT miffed, reports the Wall Street Journal.

McGinness’s faith in the community and the notion of public art is understandably shaken. “When I caught one of the first few disappearing, I was mildly amused. [But later], it felt a little more aggressive. It made me just plain angry,” he told the WSJ, noting that the installation didn’t make it more than three days before it was largely dismantled by thieves.

Twelve of the signs, which cost about $800 each to produce and install, have been replaced, this time using hardware that should be trickier to remove. “There’s a lot of expense involved, and a lot of labor. To have an individual steal them or to have them stolen by the public really flips that mind-set,” McGinness lamented.

While the New York Police Department is aware of the thefts and working to curtail them, for now we can only hope that one of the criminals will be stupid enough to try to sell a sign on Ebay.