Earlier quoted context omitted.
To clarify, this is not considered a naked short because in this situation there is a share that is known to exist. Re-borrowing the same share does not make it a naked short.
It has to not only exist, but be obtainable. In any case, the important limit here is that financial firms are not supposed to allow hedge funds or other entities to assume short positions for more stock than exists, because if it becomes necessary to execute the trades to resolve the shorts, that extra 40% will fail to deliver, because those shares don't exist. The SEC actually keeps a list of trading companies with…
"Naked shorting is the illegal practice of short selling shares that have not been affirmatively determined to exist"
- https://www.investopedia.com/terms/n/nakedshorting.asp
> that extra 40% will fail to deliver, because those shares don't exist
This is not true because all shorts don't have to be covered simultaneously.
> The SEC actually keeps a list of trading companies with high rates of failure to deliver as a means of detecting naked shorting
Funnily enough, $GME had very high failure to deliver rates in December [0] but this is not necessarily due to the short interest.
[0] https://www.reddit.com/r/wallstreetbets/comments/l97ykd/the_...