May have been a short position covered and put back in the CIBC account. I think BOW posted the short position and it was only around 20-30k on june 15th. They may have intended to short after that date and maybe quickly had to cover due to buying pressure?

I beleive its also possible that sometimes there are unrecorded short positions that don,t show up in the bi-weekly. I read something on this a few weeks ago, but can,t remember where.

Also, the trade could have other reasons, the fact is,we don,t know, but can only guess.