The top pre-market NASDAQ Stock Market gainers are: Vital Images, InfoSpace, Fortinet, Micromet, and Citrix Systems. The top pre-market NASDAQ Stock Market losers are: Akamai Technologies, Flextronics International, InterMune, Mellanox Technologies, and Urban Outfitters.

Gainers

Vital Images Inc. (VTAL) stock jumped 31.59 percent to $18.66 in the pre-market trading, as it agreed to be acquired by a subsidiary of Toshiba Medical Systems for $18.75 a share, or about $273 million in the aggregate, through a cash tender offer followed by a merger. It is anticipated that Toshiba Medical subsidiary will commence a tender offer for all of the outstanding shares of Vital Images by May 11. It is expected that the transaction will close in the second or third quarter of 2011.

On a preliminary basis, Vital Images' revenue for the first quarter of 2011 was better than expected for its non-Toshiba Medical business, although revenues pertaining to Toshiba Medical were negatively affected by Toshiba Medical's business. While overall first quarter 2011 revenue was better than first quarter of 2010, it will be slightly below analyst expectations. Earnings were largely in-line with expectations. Vital Images expects to report full first quarter financial results on May 2; however, in light of the pending transaction, the first quarter earnings conference call on May 5 has been cancelled.

InfoSpace Inc. (INSP) stock advanced 16.17 percent to $10.20 in the pre-market trading, as its first quarter earnings and revenue exceeded Street view. Profit was $2.1 million or 6 cents a share, up from $1.5 million or 4 cents a share last year. Adjusted profit rose to $3.2 million or 9 cents a share from $2.1 million or 6 cents a share. Revenue was $61.63 million, compared to $61.77 million last year. Analysts had expected profit of 5 cents a share on revenue of $58.99 million.

InfoSpace expects second quarter earnings of $1.5 million to $2.5 million or 4 cents to 7 cents a share and revenue of $59 million to $62 million, while Street predicts profit of 4 cents a share on revenue of $58.43 million.

Fortinet Inc. (FTNT) stock improved 12.13 percent to $46.79 in the pre-market trading, as its first quarter earnings and revenue exceeded Street view. Adjusted profit was $13.9 million or 17 cents a share, up from $5.8 million or 8 cents a share last year. Revenue grew 34 percent to $93.3 million. Analysts had expected profit of 14 cents a share on revenue of $86.86 million.

In addition, Fortinet said its board has approved a two-for-one stock split of the company's shares, to be effected in the form of a stock dividend. The stock split will entitle each stockholder of record at the close of business on May 9, to receive one additional share for every one share owned as of that date. The additional shares resulting from the stock split are expected to be distributed by the company's transfer agent on or about June 1. Upon the completion of the stock split, Fortinet will have about 153 million shares of common stock outstanding.

Micromet, Inc. (MITI) stock grew 10.77 percent to $7.30 in the pre-market trading.

Citrix Systems, Inc. (CTXS) stock gained 5.97 percent to $82.48 in the pre-market trading, as its first quarter earnings and revenue exceeded Street view. Adjusted profit was $96.64 million or 50 cents a share, up from $75.05 million or 40 cents a share last year. Revenue grew 18 percent to $490.89 million. Analysts had expected profit of 42 cents a share on revenue of $475.30 million.

Citrix expects second quarter adjusted earnings of 54 cents to 55 cents a share and revenue of $515 million to $525 million, while Street predicts profit of 54 cents a share on revenue of $516.67 million. For the full year 2011, the company expects adjusted earnings of $2.38 to $2.41 a share and revenue of $2.14 billion to $2.17 billion, while Street analysts predict profit of $2.32 a share on revenue of $2.13 billion.

Losers

Akamai Technologies Inc. (AKAM) stock plunged 12.42 percent to $35.89 in the pre-market trading, as it guided second quarter below Street view. The company said it a conference call that it expects adjusted earnings of 34 cents to 37 cents a share and revenue of $270 million to $280 million, while Street predicts profit of 38 cents a share on revenue of $280.33 million.

Akamai reported its first quarter earnings of $50.6 million or 26 cents a share, up from $40.9 million or 22 cents a share last year. Normalized earnings were $72.2 million or 38 cents a share, up from $66.0 million or 35 cents a share last year. Revenue rose to $275.95 million from $240.03 million. Analysts had expected profit of 37 cents a share on revenue of $272.02 million. The company also said its board of directors has authorized a second $150 million expansion of its share repurchase program, which is expected to be funded by cash from operations. The program will be extend for 12 months beginning in May 2011.

Flextronics International Ltd. (FLEX) stock tumbled 7.32 percent to $6.96 in the pre-market trading, as its fourth quarter earnings missed Street view. Adjusted earnings were $162 million or $0.21 per share, up from $130 million or $0.16 per share last year. Sales increased 15 percent to $6.9 billion. Analysts had expected earnings of $0.22 per share on revenue of $7.28 billion. Looking ahead, the company expects first quarter adjusted earnings of $0.20 to $0.23 per share, and revenue of $7.1 billion to $7.6 billion, while Street predicts profit of $0.23 per share on revenue of $7.61 billion.

Flextronics said its board has authorized the repurchase of up to $200 million of the company's outstanding ordinary shares. This authorization is in support of the current shareholder authorization for the repurchase of up to 10 percent of outstanding ordinary shares. This authorization is in addition to the programs previously announced on May 28, 2010 and August 12, 2010, each for $200 million in share repurchases and recently concluded.

InterMune Inc. (ITMN) stock fell 7.18 percent to $45 in the pre-market trading. Loss for the first quarter narrowed to $32.1 million or $0.57 per share from $34.1 million or $0.66 per share last year. Revenue rose to $6.4 million from $6.1 million. Analysts had expected a loss of $0.78 per share on revenue of $5.05 million.

Mellanox Technologies, Ltd. (MLNX) stock slid 6.51 percent to $27.57 in the pre-market trading. Loss for the first quarter was $1.6 million or $0.05 per share, compared to a profit of $5.2 million or $0.15 per share last year. Adjusted profit was $9.2 million or $0.24 per share, down from $10.4 million or $0.29 per share last year. Revenues rose to 55.1 million from $36.2 million. Analysts had expected earnings of $0.14 per share on revenue of $54.81 million.

Urban Outfitters Inc. (URBN) stock declined 5.92 percent to $31.14 in the pre-market trading. The company said it will sell Leifsdottir brand exclusively at Anthropologie stores and through its direct-to-consumer business and will discontinue wholesale distribution with the conclusion of spring deliveries. Johanna Uurasjarvi, Creative Director for Leifsdottir, will return to the Anthropologie brand as the Executive Creative Director of Anthropologie Product Design.

The company expects to record one-time costs of approximately $2.7 million in the first quarter of the current fiscal year for the disposal of certain Leifsdottir assets, disposition of inventory and other related costs. Urban Outfitters also announced quarter-to-date comparable retail segment sales through the Easter holiday weekend of low single-digit negative.

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