It all revolves around borrowing, then returning, and then borrowing stock again. This would normally suggest a precursor to a short-selling campaign, but there is and has been basically very close to zero actual shorting activity taking place in POS (see following notes).
Sans actual shorting activity, it does beg the question why they continue to borrow and return shares. Bloody good question. It may relate to certain portfolio management activities, which might explain it, but that's just an educated guess. BAML might also be writing/selling covered call options in POS, which might necessitate borrowing underlying stock to risk-manage their book. I don't track the oppies market, so I cannot say what, if any, activity there is in POS on that front. Can't imagine it would be much, though.
What we can say, with a reasonable degree of certainty is that basically zero shorting is being undertaken. What little is occurring from time to time appears to be covered within 3 days of it occurring (read on).
Notes: How can we be certain that shorting is not current present in POS and has not been present in any meaningful way over the past 3 years?
This Shortman link shows the self-disclosed short positions in POS over the past 3 years (click appropriate link above the chart). With the exception of some relatively short periods of very minor shorting activity (maxed out at ~786,000 shares shorted back in Feb, 2018 - a very small amount relative to overall SOI), there has basically been zero shorting.
It's important to understand that Shortman obtains and reports its data directly from ASIC on a T+4 lagging basis. For many years up until late last year Shortman would include short sale data from ASX for those first 3 days before making it into the longer-term ASIC dataset. However, all that stopped in late-2019 and today the shorting chart only shows ASIC data on a T+4 lagging basis (i.e. no ASX data covering from T+1 to T+3). The Shortman website contains detailed notes/tweets that explain it all for anyone who is interested.
Shortman does provide a link to the ASX data for the previous day's shorting activity (here) on a rolling previous day basis. As an example, clicking that link tonight (Wed 19 Feb) shows data for 18 Feb. Scroll down the text list and there is no entry for POS, meaning no shorting activity for 18 Feb. Over the past couple of months when I have periodically checked there has been the odd day here and there in which a very small daily short volume in POS has been reported (eg: say ~12,000 shares). However, none of those positions have ever made their way into the ASIC short sales dataset, which tells me that those small shorts reported in the rolling previous day's data had already been fully covered (reversed) by T+4 and, thus, never made into the ASIC dataset.
It's worth pointing out that Short sales in Australia are required to be self-disclosed and there is always the possibility that there may be a degree of non-compliance. However, it's also worth pointing out that lodgement of F603s, F604s and F605s (various substantial holder notices) is also done on a self-disclosure basis. Given BAML is compliant with its substantial holder self-disclosure obligations, I cannot imagine them not being compliant with their short-selling self-disclosure obligations and exposing themselves to risk of fines by not self-disclosing any longer-term shorting activity - especially when they are demonstrating compliance in other self-disclosure areas.
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