If it is a registered account, it does not matter. Otherwise:

"In order for the conditions in subsection 85.1(1) to be satisfied, the purchaser must be a Canadian corporation"

Canadian corporation, as defined in paragraph 89(1)(a)

The full sentence is:

"In order for the conditions in subsection 85.1(1) to be satisfied, the purchaser must be a Canadian corporation, as defined in paragraph 89(1)(a), and the vendor must hold the shares (exchanged shares) in the acquired corporation as capital property."

So find 89(1)(a) and you may have your answer.