The law says you have to be the holder of a registration certificate. But holder seems to mean that you're in the computer. (the paper copy you have might have been revoked)
The law then says you have to present the certificate upon demand to a peace officer, which seems to mean that you're in possession of the paper.

But the law also says that the staff at the Canadian Firearms Program are committing an indictable offence every time they transfer a firearm, and that gets ignored. I wonder if Suzanne Legault will take up this 'injustice'.