Yes, the canny Baker Brothers own a bit of almost everything biotech. As of their most recent 13f, IDRA constituted .15% of their portfolio. PCYC constituted 17.7% of their portfolio. According to my calculations, this means they have bet about $12 million on IDRA and $1.06 billion on PCYC. Note: In the past, they have also bet on some notable losers, such as ARIA, VVUS, etc. As of their 13f, they only had a tiny (for them) position in PBYI, which has doubled since then. On balance, obviously, they pick more winners than losers. And it's always worthwhile to see what they're holding.