According to the Nikkei, on August 7, USB Japan apparently purchased 8 million shares of Nova stock, and then loaned the shares to its bank, UBS AG, the same day.
As of the announcement, Nova has not yet confirmed the transaction.
Comment: I was wondering if this was a sign that Nova has turned the corner, but I don't see that this stock acquisition changes anything--Nova is still short of money and Sahashi is firmly in control. That said, it makes me wonder if these 8 million shares aren't the same 8 million that PNB Paribas acquired earlier.
Minor update: This little blurb in Sponichi would suggest that the trade has nothing to with PNB Paribas.