Can a person keep a green card if they get a permanent job in Canada?

My ex has taken a permanent job in Canada but has kept his green card. He keeps telling me I have to move to Canada too.
I don't want to move there at all, my life is here in America. Will he lose his green card?

The 1 day a year residency requirement is a myth. If the CIS finds out he's living and working full time in Canada they'll declare his immigrant status to have been abandoned.

ask him to inquire about converting to the commuter status, if he is working near the border area of Canada, this would only work if both live near the border.
No, he will not lose his Green Card.

The residency requirements are 1 day per year must be spent in the U.S.

Though, it is difficult to prove or disprove just exactly how much time one spent in the U.S.

So the answer is definitely, no loss of Green Card.
A permanent resident becomes an applicant for admission if they are absent the U.S. for more than 180 days. If you anticipate being outside the U.S. for more than 180 days you are supposed to file a Form I-131, Application for Travel Document, with USCIS. That will preserve his rights to residency for up to two years.

You can see the fact sheet at USCIS. Scroll down to and click on "Get a Re-entry Permit."
http://www.uscis.gov/portal/site/uscis/m...
no>>>GIVE IT BACK