Commercial Bankshares ( CLBK) rocketed 29% after Colonial BancGroup ( CNB) agreed to buy the Miami-based regional lender for $317 million, or $49.36 a share. Commercial shares were up $11.01 to $48.51. Colonial shares were down a nickel to $24.55.

RLI ( RLI) jumped after fourth-quarter profit at the insurer more than tripled to $55.7 million, or $2.23 a share. Shares of the Illinois-based company were rising $3.51, or 7%, to $54.51.

BlackRock ( BLK) rose after the New York-based asset-manager reported that fourth-quarter profit more than doubled following its merger with Merrill Lynch's ( MER) money-management group. BlackRock earned $211.7 million, or $1.61 a share, which was 8 cents higher than the Thomson Financial estimate. Shares were gaining $6.19, or 3.7%, to $175.47.

Nasdaq Stock Market ( NDAQ) declined after a Morgan Stanley analyst reduced his rating on the exchange to equal-weight from overweight. Meanwhile, the war of words between the Nasdaq and the London Stock Exchange continues, as the deadline for Nasdaq's hostile bid for the London bourse draws near. Shares were falling 71 cents, or 2.1%, to $33.21.

Van der Moolen ( VDM) dropped on word the Dutch specialist firm will lay off 30% of the employees at its U.S.-based Van der Moolen Specialists division. The layoffs mean 55 workers will lose their jobs. Shares were losing 24 cents, or 4%, to $5.75.