Only if you own paper claims to gold that do not have the physical, ounce for ounce, to cover the actual claims. If a person is depending on a fiduciary to hold his gold, as long as the fiduciary is honest and has the gold it should be no problem.

I would not depend on the Comex to be able to deliver all the gold that is sold short. If more gold is demanded than they can deliver it is likely they would settle in fiat currency rather than the real thing. That might be a problem for some, if the price was rising and no physical to be had.

John