Secondary transactions, or sales from one PE investor to another, have exploded this year. So far in 2010, there have been 121 completed secondary transactions, according to the PitchBook Platform. That's almost triple 2009's total of 43. Additionally, the median deal size has almost doubled from $215 million last year to $400 million in 2010. The largest secondary deal so far this year was the $1.785 billion acquisition of a 42.5% stake in Univar from CVC Capital Partners by Clayton, Dubilier & Rice, which closed in November. This year, the B2B Products and Services industry has been responsible for most of the secondary deal flow, accounting for 34.7% of the transactions, followed by B2C Products and Services with 33.9% and Information Technology with 11.6%.