The hold back is 20% to 50%, as posted
here. As for my
napkin math the goal was to get
conservative results, so I took only 5 largest institutional shareholders , which all have brokerages, so are capable to lend their shares directly, and assumed that they've lent/going to recall only 50% of their shares.
To re-iterate what I've mentioned before, although as a group institutional shareholders own majority of TSLA shares, the five I took are not. All are large investment companies with limited appetite for unmitigated risk. I just don't see them not recalling their shares and risking others deciding the fate of the company they are so heavily invested in ($44.5B) on behalf of their investors. This just does not look as a plausible scenario to me, and professionals having decades of experience in shorting seem to have the same opinion.