Midday Leaders and Laggards: Nasdaq 100

The index, which includes 100 of the largest nonfinancial securities listed on the Nasdaq Stock Market, gained 9.95 points to 1,826.50 in midday trading. The broader Nasdaq composite added 0.13 points to 2,245.51.

Light, sweet crude for August delivery fell $4.92 to $140.37 in morning trading on the New York Mercantile Exchange. Earlier, the contract sank as low as $140.12, or $5.17 below Thursday's settlement price.

Shares of Yahoo Inc. jumped $2.52, or 11.8 percent, to $23.87. Microsoft Corp. said Monday that a change in Yahoo Inc.'s board would encourage it to renew its takeover bid.

Shares of United Airlines parent UAL Corp. gained 30 cents, or 7.8 percent, to $4.16 as crude prices slipped. The profitability of airline operators is closely linked to jet-fuel costs.

Shares of Leap Wireless International Inc. added $1.94, or 5.3 percent, to $38.37.

On the declining side, shares of Teva Pharmaceutical Industries Ltd. shed $4.23, or 9 percent, to $42.97. The drug maker posted disappointing results Monday from a higher-dose trial of multiple sclerosis drug Copaxone.

Shares of VeriSign Inc. slipped $2.24, or 6.1 percent, to $34.50. The security software company's chief executive and president resigned, effective Monday.

Shares of Monster Worldwide Inc. fell 78 cents, or 4.2 percent, to $17.63.