We frequently publish stories of animals that are reunited with their owners thanks to microchips. Simba has just been reunited with his owners, who had lost him a year ago. 

In this case Simba had not been microchipped, but his owners were traced via Lost and Found (he has now been microchipped).  Simba had lost weight while he lived as a stray, and he will need considerable grooming to get his matted long-haired coat back to its proper condition.