Interactive is one that has been commented on this board a few times. I have contacted them in the past for clarity and verified for myself. HPIL was on their shortable list and the rep I spoke to placed a test trade for confirmation. No exhorbitant fees either, contrary to other penny shorting commentary Ive seen.
TDA, to the other extreme, wont even allow short positions on tickers below $4. Their explanation to me was that they didnt consider share price below that threshold as "being marginable". Which to me is just their good samaritan way of controlling trading to help protect values of low pps tickers.
I've seen other commentary about "astute traders knowing" and "check the short interest report" and "thats just a clickbait site" and "the short volume is just MMs doing their jobs" etc... and what I have found is that the short interest report is only a snapshot of borrowed shares not returned as of the biweekly report's date and time. Comes out every other Friday. That leaves a rolling 9 business day period in which shorts can roundtrip (mon-fri + mon-thu) so that their borrowed shares dont show up on the snapshot report as not returned. I see commentary like "insignificant" because of the low volume showing up on the interest report.
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