A regular short involves borrowing a share and selling it. A naked short involves selling a stock that one neither has nor has borrowed. Over subscribed means there are more shares accounted for than the A/S or O/S. Let's say there are 3 billion shares. But when we tally up the shares by interviewing all the owners we find that 3.6 billion shares are owned. That means 600 million shares were borrowed from existing owners and sold on the open market to other owners. These shorters are not necessarily naked shorts. That's because the shares were borrowed. Now if the tally were to exceed 6 billion shares then for sure naked shorting is going on because then there are shares sold which are not borrowed. Krombacher