Among the companies with shares expected to actively trade in Friday's session are F5 Networks Inc. (FFIV), Rigel Pharmaceuticals Inc. (RIGL) and Radware Ltd. (RDWR).

Network-gear maker F5 Networks slashed its view of fiscal second-quarter results after business from customers in North America arrived below expectations. Shares tumbled 17% to $74.90 premarket. Others in the industry also saw their shares fall on F5's pessimistic outlook. Juniper Networks Inc. (JNPR) shares dropped 5.6% to $17.10, Riverbed Technology Inc. (RVBD) shares were off 2% at $14.65, and Cisco Systems Inc. (CSCO) shares fell 3.3% to $20.34.

Rigel, a small clinical-stage drug developer, is facing very big investor concerns after its partner, pharmaceutical heavyweight AstraZeneca PLC (AZN, AZN.LN), released less-than-stellar results about their drug candidate, fostamatinib. Following a Phase 3 study, the rheumatoid arthritis treatment appears to be an inferior product to Abbott Laboratories' (ABT) well-established treatment Humira, according to two analysts. Rigel shares fell 32% to $5.13 premarket.

Radware, which makes application security systems for virtual and cloud data centers, said results for its first quarter will miss its previous estimates, citing weaker-than-expected revenue in Europe, the Middle East, Africa and China. Shares fell 18% to $31.00 premarket.

Exide Technologies Inc. (XIDE) has retained an adviser to review financing options to maximize value for the battery manufacturer's shareholders. Shares surged 35% to $1.85 premarket.

Saba Software Inc. (SABA) said it will be unable to regain compliance with the company's SEC filing requirements for continued listing of its common stock on the Nasdaq Global Select Market by the previously reported April 4 deadline. Saba isn't current in its periodic report filing requirements with the SEC as a result of the company's pending restatement of prior financial results. Shares fell 11% to $6.91 premarket.

Energy Transfer Partners L.P. (ETP) said it is offering 12 million units. The oil and gas company, which had around 305.6 million units outstanding as of March 31, intends to use the proceeds to pay down debt and for general purposes. Units were down 4.2% to $48.26 premarket.

Latin American wireless operator NII Holdings Inc. (NIHD) has agreed to sell its Peruvian operations to Empresa Nacional de Telecomunicaciones S.A. (ENTEL.SN) for around $400 million as it narrows its focus to Mexico and Brazil. Shares rose 11% in premarket trading to $5.02.

Valero Energy Corp.'s (VLO) board has approved the spinoff of its retail business, a move that comes as the company reshuffles its portfolio. Shares were up 1.5% at $42.07 premarket.

Medical-device maker Mako Surgical Corp. (MAKO) said it has won a court order barring a former sales manager from working for a competitor, Blue Belt Technologies. Shares climbed 1.3% to $10.64 premarket.

 
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Advance Auto Parts Inc. (AAP) has eliminated its position of chief operating officer, and appointed a new president in a management shake-up.

Brandywine Realty Trust (BDN) has launched an offering of 10 million shares, intending for the proceeds to be used by its operating partnership for acquisitions, development, debt refinancing or other general uses. The office landlord recently had around 143.7 million shares outstanding.

Moody's Investors Service raised its rating on Dillard's Inc. (DDS) one notch closer to investment grade, noting the department-store operator's continued growth in sales and operating margins.

Hanesbrands Inc. (HBI) expects first-quarter per-share earnings to significantly top analysts' estimates, although revenue will be lower than expected as delayed income-tax returns contributed to a lackluster retail environment. The apparel manufacturer also initiated a quarterly dividend.

Hewlett-Packard Co. (HPQ) Chairman Raymond Lane is giving up his powerful post--a surprise move that heralds yet another shakeup of the technology company's long-beleaguered board.

Rosetta Stone Inc. (RST) said it will close all of its iconic yellow kiosk locations and cut 245 part- and full-time employees as the language-learning company moves to become an online operation.

A jury in Nevada decided Thursday that a local UnitedHealth Group Inc. (UNH) unit is responsible for two members who contracted hepatitis C, and awarded $24 million in compensatory damages.

WD-40 Co.'s (WDFC) fiscal second-quarter profit fell 1.2% as the maintenance and cleaning products company's weaker Americas sales and higher expenses masked improvements in the Europe and Asia-Pacific regions. The company beat earnings expectations and raised its income outlook for the year.

Xyratex Ltd. (XRTX) swung to a fiscal first-quarter loss as the company posted double-digit declines in its data-storage segment and its smaller hard-disk-drive business.

Write to Anna Prior at anna.prior@dowjones.com

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