We were skeptical at first, as this sounded too weird to be true, but it seems "three or four" plainclothes SFPD officers did, in fact, accompany private Apple detectives to the home of Sergio Calderón, a 22-year-old resident of Bernal Heights on the hunt for a missing iPhone 5. Shortly after the initial story broke, the San Francisco Police Department said it didn't know of the incident or lost phone, but after speaking to Apple and the captain of the Ingleside police station, spokesman Lt. Troy Dangerfield confirmed to SF Weekly that some officers did assist Apple to the address in July.
Calderón told SF Weekly that in July six people wearing badges came to his house looking for a lost phone that had been traced to him via the phone's onboard GPS. According to SF Weekly, "Calderón said none of them acknowledged being employed by Apple, and one of them offered him $300, and a promise that the owner of the phone would not press charges, if he would return the device." Apparently the SFPD officers didn't enter his home, but the Apple detectives did, searching his car, house and computer but never mentioning an iPhone 5 prototype specifically.
Dangerfield indicated he would follow up with Calderón to learn more. As for Calderón's recollection of the events, he says the visitors indicated they were SFPD, which is why he let them in. Further, he claims family members were threatened about their immigration status.
When CNET originally reported the story, they said: "The man gave police permission to search the house, and they found nothing, the source said." Then the SFPD said they found no records of an investigation. The man whose name and number were given to Calderón was traced to a LinkedIn profile of someone who appears to work at Apple. So the latest wrinkle is that the SFPD now confirms that officers did accompany Apple detectives to Mr. Calderón's dwelling, where detectives (not SFPD) went through his stuff looking for a "lost phone." We're hoping Apple is able to confirm or deny that their detectives did search Mr. Calderón's property.
AllThingsD has a succinct description of what happened here.