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Reverse graffiti ads: 'Clean' or crime?

The city of San Francisco wants to crack down on so-called reverse graffiti, the practice of stenciling a brand name or company logo into a dirty spot using high-pressure hoses, creating an advertisement of sorts in the white space that remains, reports ABC’s KGO-TV in San Francisco.

In an examination of the practice, San Francisco’s Department of Public Works spokesman Gloria Chan told KGO that “we're going to be investigating and taking a look at what enforcement code this falls under." In the meantime, she asked companies that have created ads using reverse graffiti to come back and wash away their signs.

But the regulations surrounding the practice are squidgy. According to reverse graffiti proponents such as GreenGraffiti, a Netherlands-based company that has been spearheading reverse graffiti campaigns for companies like Sony and Heineken since 2007, the practice is “clean” advertising, since it doesn’t use paper, billboards or chemicals. "What we're doing is something that's not necessarily illegal, but also not necessarily legal, it's a little bit in a gray zone,” GreenGraffiti founder Jim Bowes told KGO.

Local laws in places like San Francisco don’t prohibit cleaning public spaces, but they do require permits for advertising in them. In this case, however, companies aren’t displaying stickers or signs, and foot traffic smudges up the ads in a matter of weeks.

But some signs have stuck around for a while — the British artist Paul Curtis, who calls himself Moose, was featured in a 2008 short film about the reverse graffiti mural he made inside San Francisco’s Broadway Tunnel as an advertisement for the cleaning product Green Works.