[mothballed]

Yeah that sounds basically impossible to prove since the onus is on them to prove the negative that you never consented to it, but my guess is since it's a civil ticket it goes through some kangaroo court where you are fucked from the get go and the judge is basically the 21st century equivalent of a red-coat.

[bryanrasmussen]

Owner's authorized agent sounds like a court would expect to see some sort of paperwork authorizing the placement of the graffiti. So when you say I told them it was ok the burden of proof falls on you that you did.

[gus_massa]

No idea about SF, but a few years ago a group painted most of the Rolling security shutters in the business in a street near my home in Buenos Aires https://www.google.com/maps/place/Uruguay+224,+C1015ABF+ABF,...

Most were nice, and some of them still survive, but a lot seem to be over painted. (It would be nice to see a image at night or Sunday, when most business are closed. Some may be still there but rolled up while the business is open.)

Anyway, I don't expect a formal paperwork, just a handshake an an oral agreement.