The top after-market NASDAQ Stock Market gainers are: Tree.Com, Vermillion, Velti, Star Bulk Carriers, and Penson Worldwide. The top after-market NASDAQ Stock Market losers are: Imris, Andatee China Marine Fuel Services, Celldex Therapeutics, Universal Display, Winn-Dixie Stores, Yahoo!, and Nvidia.

Gainers

Tree.Com, Inc. (TREE) stock jumped 34.26 percent to $7.25 in the after-market trading, as Discover Financial Services (DFS) agreed to buy substantially all of the operating and related assets of Home Loan Center, a unit of Tree.com, for about $55.9 million. The acquisition is expected to close by the end of 2011. The acquisition will add a home loan component to Discover's direct-to-consumer banking products, which include credit cards, personal loans, private student loans, certificates of deposit, savings accounts and Roth individual retirement accounts.

Discover intends to originate eligible consumer mortgages to sell in secondary markets on a servicing-released basis. The company anticipates that the acquisition will have a nominal impact on its 2012 earnings. Home Loan Center, which operates as LendingTree Loans, originates and processes consumer mortgage loans nationwide.

Vermillion, Inc. (VRML) stock climbed 9.26 percent to $6.37 in the after-market trading. The company said its OVA1 Blood Test was found to be a more accurate detector of Ovarian cancer than the currently recommended CA 125 blood test. The test developed by Vermillion, is offered by Quest Diagnostics Inc. (DGX) in the United States and India. The data from the American College of Obstetrics and Gynecology study was published online ahead of print in the June 2011 edition of its official publication. Quest and Vermillion participated in the study, with neither company having any involvement in the development of the manuscript.

American College of Obstetrics and Gynecology (ACOG) guidelines for the management of ovarian masses recommend the evaluation of factors such as menopausal status and CA 125 blood test levels. Based on the evaluation, patients are divided into low and high risk categories. Treatment plans and surgical referral are planned accordingly. The study compared the CA 125 test and the OVA1 test in 516 women scheduled for surgery for an ovarian mass. Results showed that 94 percent of malignancies were accurately detected by OVA1 compared with 77 percent with CA 125. In premenopausal women, the detection rate was 91 percent versus 58 percent.

Study investigator Rachel Ware Miller, said younger women and early stage cancers were not receiving appropriate surgical staging and treatment, and that an effective preoperative test could have a favorable effect on women's health as survival is better in these populations. OVA1 is the first test cleared by the FDA for aiding in the pre-surgical evaluation of a woman's ovarian mass for cancer, and also is the first protein-based In Vitro Diagnostic Multi-Variate Index Assays (IVDMIA), a new class of software-based diagnostics.

Vermillion performed an estimated 3,080 OVA1 tests during the first quarter of 2011, representing volume growth of 5 percent over the fourth quarter of 2010. For the second quarter, the company expects 3,200 to 3,500 OVA1 tests to be performed.

Velti Plc (VELT) stock grew 4.98 percent to $18.99 in the after-market trading. Adjusted loss for the first quarter widened to $5.20 million or $0.11 per share from $3.19 million or $0.08 per share last year. Revenue rose 82 percent to $29.55 million. Analysts had expected a loss of $0.15 per share on revenue of $26.56 million.

Separately, Velti said it plans to buy the balance equity ownership that it does not already own of Casee, a mobile ad exchange and mobile ad network business in China. Velti had acquired 33 percent of Casee in 2008. Velti said the acquisition would give it a crucial stronghold in China. The acquisition would also give the company a self-service mobile marketplace platform that connects more than 10,000 mobile content publishers including Sohu and Baidu, and over 2,000 iPhone and Android application partners.

Star Bulk Carriers Corp. (SBLK) stock gained 4.78 percent to $2.41 in the after-market trading. Adjusted earnings for the first quarter was $1.3 million or $0.02 per share, compared to $1.5 million or $0.02 per share last year. Revenue marginally rose to $29.5 million from $29.3 million. Analysts had expected a loss of $0.02 per share on revenue of $24.05 million. The company said its board of directors declared a cash dividend of $0.05 per outstanding share of its common stock for the first quarter, payable on or about June 1, to shareholders of record as of May 23.

Penson Worldwide Inc (PNSN) stock increased 4.17 percent to $3.25 in the after-market trading. The company said it believes that the recent declines in its stock price appear to be related to its recent Form 10-Q disclosure of a concentrated collateral position associated with Retama Development Corporation related receivables. The company currently expects to resolve this situation without a loss, but even if a loss were realized, Penson said it would have no impact on the company’s solid regulatory capital or sound financial condition.

As reported in the company’s Form 10-Q, as filed with the Securities and Exchange Commission on May 9, Penson has about $42.6 million in non accruing receivables collateralized by securities related to the Retama Development Authority, which have declined in liquidity. The $42.6 million of receivables represent only 0.49 percent of Penson’s $8.7 billion in average daily customer balances during the first quarter of 2011. Penson regularly reviews the value of the collateral, including a recent third party appraisal of the real estate underlying the Retama facility.

The company also announced the resignation of Thomas Johnson from its board of directors. Based on Johnson’s position as chief executive officer of Call Now, Inc, a holder of a portion of the Retama related collateral, both Johnson and Penson Worldwide felt it appropriate for him to resign his position at this time.

Losers

Imris Inc. (IMRS) stock plunged 9.81 percent to $7.45 in the after-market trading. Loss for the first quarter widened to $4.59 million or $0.10 per share from $2.06 million or $0.06 per share last year. Revenue fell 8.3 percent to $11.1 million, due to lower installation activities and reflective of the quarterly variability in the business.

Andatee China Marine Fuel Services Corp. (AMCF) stock plummeted 9.62 percent to $3.10 in the after-market trading. The company lowered its fiscal 2011 earnings guidance to range of $10 million to $12 million from previous forecast of $11 million to $13 million, as a result of rising cost of inventory (rising oil prices) and a conservative approach to potential margin consolidation. The company reiterated its 2011 revenue outlook of $275 million to $325 million. The company reported its first quarter earnings of $2.3 million or $0.23 per share, up from $1.4 million or $0.16 per share last year. Revenue grew to $44.26 million from $29.78 million.

Celldex Therapeutics, Inc. (CLDX) stock fell 8.05 percent to $3.77 in the after-market trading.

Universal Display Corp. (PANL) stock tumbled 8.01 percent to $43.42 in the after-market trading.

Winn-Dixie Stores Inc. (WINN) stock slid 7.88 percent to $7.36 in the after-market trading.

Yahoo! Inc. (YHOO) stock declined 6.23 percent to $16.10 in the after-market trading. The company said the Alibaba Group, in which it has a 43 percent stake, has transferred its online-payments unit Alipay to a company controlled by the Group's CEO Jack Ma - depriving Yahoo of a valuable asset even as it grapples with intense competition in the search business and looks for newer revenue streams. Yahoo said it and another Alibaba stakeholder, Japan's Softbank Corp., were not aware of Alipay's ownership transfer of last August and the subsequent restructuring.

On March 31, Yahoo! and Softbank were notified by Alibaba Group of two transactions that occurred without the knowledge or approval of the Alibaba Group board of directors or shareholders. The first was the transfer of ownership of Alipay in August 2010. The second was the deconsolidation of Alipay effective in the first quarter of 2011.

Yahoo! disclosed the restructuring in its 10-Q after discussions with Alibaba Group and obtaining a better understanding of this complex situation. Yahoo! further said it continues to work closely with Alibaba and Softbank to protect economic value for all interested parties.

Nvidia Corp. (NVDA) stock decreased 2.98 percent to $19.89 in the after-market trading. Profit for the first quarter was $135.2 million or $0.22 per share, down from $137.6 million or $0.23 per share last year. Adjusted earnings declined to $165.7 million or $0.27 per share from $169 million or $0.29 per share. Revenue fell 4 percent to $962 million. Analysts had expected profit of $0.19 per share on revenue of $946.89 million.

For the second quarter, the company expects revenue to be up 4 percent to 6 percent sequentially, implying revenue of $1.00 billion to $1.02 billion, while Street predicts $991.60 million. The company projects second quarter gross margin to be 50.5 percent to 51.5 percent.