The black-and-white puppy named Louie was taken from the city shelter at 1200 15th St. around 2 p.m. last Thursday, Animal Care and Control spokeswoman Deb Campbell said.
The dog was returned to the shelter around 7 p.m. Tuesday by a good Samaritan who reported getting the dog from someone on the street, Campbell said. "The person was just going to let him go so the good Samaritan took him," Campbell said.
She said the dog is "happy, healthy" and is going back up for adoption soon.
Anyone with information about the theft can call Animal Care and Control at (415) 554-9400.