The top after-market NASDAQ Stock Market gainers are: PAETEC Holding, SIGA Technologies, MYR Group, Zalicus, and Maiden Holdings. The top after-market NASDAQ Stock Market losers are: DragonWave, Quidel, Abaxis, BJ's Restaurants, and Signature Bank.

Gainers

PAETEC Holding Corp. (PAET) stock gained 4.65 percent to $4.95 in the after-market trading.

SIGA Technologies, Inc. (SIGA) stock increased 3.83 percent to $10.04 in the after-market trading.

MYR Group, Inc. (MYRG) stock gained 2.68 percent to $23.40 in the after-market trading.

Zalicus Inc. (ZLCS) stock increased 2.66 percent to $2.70 in the after-market trading. Oppenheimer & Co. initiated coverage of Zalicus with an outperform rating and a price target of $4. The brokerage said Zalicus could get up to $15 million in annual royalties from the pain drug Exalgo, a drug developed by Zalicus and marketed by Covidien PLC. The company also has a promising pipeline of drug candidates, including the experimental rheumatoid arthritis drug Synavive, and eye allergy treatment Prednisporin, Oppenheimer said in a note to clients.

Maiden Holdings, Ltd. (MHLD) stock rose 2.27 percent to $9.48 in the after-market trading.

Losers

DragonWave Inc. (DRWI) stock declined 3.96 percent to $6.07 in the after-market trading. The company said Brian McCormack, Vice President of Worldwide Sales has submitted his resignation and will be leaving the company. Effective immediately, regional sales executives will report directly to Peter Allen. McCormack will support this transition over the next 45 days before moving on to pursue other interests.

Quidel Corp. (QDEL) stock decreased 3.77 percent to $15.30 in the after-market trading.

Abaxis Inc. (ABAX) stock declined 3.64 percent to $27.77 in the after-market trading.

BJ's Restaurants, Inc. (BJRI) stock decreased 3.18 percent to $53.30 in the after-market trading. Zacks Equity Research maintained its long-term neutral rating for BJ's Restaurants. While we are optimistic on the company’s unit growth potential and solid same-same restaurant sales, the negative impact from commodity inflation as well as increased competition compel us to remain on the sidelines, Zacks said in a note to clients. Zacks said BJ’s is also, like all restaurant companies, susceptible to higher input costs, which will lessen the magnitude of margin rebound. The total commodity basket is expected to grow 4 percent in the second half of fiscal 2011.

Signature Bank (SBNY) stock moved down 2.87 percent to $56.85 in the after-market trading. The company announced an underwritten public offering of 4.1 million common shares. The Bank will also grant to the underwriters a 30-day option to purchase up to 615,000 additional common shares to cover overallotments, if any. BofA Merrill Lynch is expected to act as sole book-running manager in the offering. Barclays Capital and J.P. Morgan are expected to act as co-managers.