Oftentimes when I find a chip that isn't registered, I am saved by the company that bought the microchip. Let's say the microchip isn't registered, but the microchip company can tell me X shelter/vet bought the chip. I can then contact them, and they often have the animal and owner on file.
Now if their system comes up with nothing, I will ask if they can check for an animal with the next/previous microchip, since chip numbers are sometimes input incorrectly. For example if I'm looking for an animal with the chip 111, I can check 110 and 112, see if 111 is a sibling or check for other animals around that intake date to see who would have been 111. Sometimes depending on their software this isn't possible, but it's worth a try.
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Mary Furby
Veterinary Medicine Supervisor
Humane Society of Southeast Texas
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