There is plenty of info about this if you are interested in facts and not the "stories" the vets and gov't tell. I learned about it on the Truth about Vaccinations yahoo group.
They also migrate. 
I'm very happy your dogs don't have cancer. Not every dog, cat or human will get cancer from a chip. 
I still would not take that crapshoot and would not implant anyone I cared about.
Nonie
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=Do you have links about this? Where?Source please?My dogs are all healthy, save for one who will be 18 years old on October 1st. He's blind and mills about the house, but he eats, drinks, cuddles and does a great imitation of a beached whale (He is a 10 lb Pomeranian). No cancer in any of them.On Aug 28, 2012, at 5:41 PM, Nonie Masterson <hachiosmom@yahoo.com> wrote:Hope they don't get cancer. Chips are pretty evil.
Nonie
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On Aug 28, 2012, at 4:14 PM, Just Murray <krismurray@gmail.com> wrote:
> I happily microchipped my two puppies. I want them back if at all possible should we get separated.
>
> ~KLM
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