Large cap biotechs stormed back after a weak 2Q12 to post a 7% gain for a third quarter in which every market cap segment finished in the black, albeit just barely for the micro-caps. For the second successive quarter the smallest names brought up the rear, though the group's 0.1% gain in 3Q12 compares favorably with the 15% slide in 2Q12.

For the year, the $5 billion-plus tier has outpaced the smaller segments, thus far posting a 26% gain. Micro-caps are up 5%, the smallest gain.