I saw that also. It's not Perceptive, not afterhours and not at that price (it was over $12).
I do wonder what is up, if that was a "typo" or if it actually happened. If it actually happened, I'm guessing someone caught wind of some great news and couldn't buy options....with thier million bucks.
i saw it to 835,000 shares at 12.36 pps is over 10 million dollar transaction...i checked sec dot gov and acrx investor section and i dont see any filings...i hardly think that size is a typo. there is a conference tomorrow morning at 11:30 est but who knows