Yes, it is a national registry. If a pet is suspected of being lost or stolen, a vet or another animal authority scans the back of the pet's neck for a chip, which will give info. Try visiting this site:
www.homeagainid.com
I had Gracie chipped when she was spayed. My vet charged $35 to implant the chip. She gave me all of the info then I went online and registered all of the info. That was a one time fee of $17.00. I have the Home Again chip.