So-called "teaser" ads for the Showtime Network series Homeland were sprayed on sidewalks throughout the District Monday.

A Georgetown Patch reader sent us a photo of one such ad, which appeared on the handicapped curbs at 29th and P Streets NW.

The ad reads simply "We were WARNED 9/30 Showtime."

The network confirmed that the ads were appearing throughout the District and in other cities including New York, Los Angeles, Atlanta, St. Louis, Chicago, Denver, Boston and Dallas.

Patch asked the District Department of Transportation (DDOT) whether there was a permitting process to allow private companies to advertise in public space. There isn't.

Monica Hernandez, a spokeswoman for DDOT, told Patch that the agency "[does] not allow for ads in public space." DDOT does not have a mechanism in place to permit the type of ad sprayed on sidewalks throughout the city.

The ad in Georgetown is just one of seveal messages. The "teaser" ads preceed a more traditional marketing campaign that will appear on public transit and in print in many of the aforementioned markets. Ads will appear on DC buses after Labor Day, the company confirmed.