Airbnb CEO Brian Chesky has been renting out his couch (the very first Airbnb) on the site for $50—illegally, it turns out, as S.F. requires all Airbnb'ers to register their pads with the city.

Chesky had said he would stop accepting guests until he went through registration, but Airbnb profile info shows he hosted in August 2015 without registration. (The requirements went into effect in February.)

The registration is supposed to prevent Airbnb'ers from renting out digs they don’t live in (essentially running hotel rooms), so it's not meant to punish Chesky’s couch setup, per se, although it technically violates the law, reports SFist.

The company fought tooth-and-nail against S.F.'s efforts to regulate, and succeeded in killing its Prop F restrictions, but has been forced to submit to the registration under S.F.’s Short-Term Residential Rental laws. [SFIST]