There are some Canada Revenue Agency technical interpretations offering the view that when a corporation issues stock of its shares to a charity or issues stock options to a charity, that's not a recognized donation. That might be one way to incentivize corporate giving: the actual giving of shares.
You might want to think about it in terms of looking at donors. You might not want to draw too stark a distinction between the privately held corporation and the sole shareholder of that corporation, because the person calling the shots is one and the same.
You can look at the rules dealing with the donation of private company shares to arrive at the same outcome. There are some submissions before the committee on removing the capital gains tax—some call it the capital gains penalty—on the donation of such shares.
I would offer you that perspective.