M&A and IPOs

Softbank has increased its takeover offer for Sprint Nextel Corp. (NYSE: S) to $21.6 billion, or around 17% more than its original proposal. Sprint also said that it has ended talks with DISH Network Corp. (Nasdaq: DISH), which it says has not put forth an acceptable formal offer to back up its announced $25.5 billion buyout interest. www.sprint.com

B&G Foods Inc. (NYSE: BGS) has agreed to acquire natural snack-food maker Pirate Brands for approximately $195 million in cash. Sellers include VMG PartnersDriven Capital Management and company founder Robert Ehrlich. www.bgfoods.com

KapStone Paper and Packaging Corp. (NYSE: KS) has agreed to acquire Longview Fibre Paper and Packaging Inc. from Brookfield Capital Partners for $1.025 billion in cash. Longview is a Longview, Wash.-based maker of containerboard, lightweight multiwall paper, specialty Kraft papers and corrugated containers. www.kapstonepaper.com

OpenGate Capital has sold its remaining stake in European supermodel agency Models 1 to company management. No financial terms were disclosed. OpenGate originally acquired the company back in 2008. www.opengatecapital.com

Chevron (NYSE: CVX) said that it plans to sell its positions in two Nigerian shallow water oil blocks. No additional details were provided. www.chevron.com

Dole Food Co. (NYSE: DOLE) has received a $12 per share buyout offer from CEO David Murdock. That represents around an 18% premium to yesterday’s closing price. www.dole.com

Exide Technologies (Nasdaq: XIDE), a Milton, Ga.-based maker of car batteries, has filed for Chapter 11 bankruptcy protection. Through the end of Q1, the company had $1.9 billion in assets and $1.1 billion in liabilities. www.exide.com

Keller Group (LSE: KLR) has agreed to acquire the piling business of North American Energy Partners (NYSE: NOA) for up to C$320 million (including a C$227.5m upfront cash payment).www.keller.co.uk

Navtech Inc., a Canadian provider of flight operations software and tools for the commercial aviation industry, has raised an undisclosed amount of funding from a structured capital fund managed byVeronis Suhler Stevensonwww.navtechinc.com

Portaero Inc., a Cupertino, Calif.-based developer of devices to treat chronic obstructive pulmonary diseases, is seeking a buyer for its assets, according to a statement from restructuring firm Gerbsman Partners. VC backers include Aberdare Ventures, Novartis Venture Funds and Versant Ventures.

Agios Pharmaceuticals, a Cambridge, Mass.-based developer of cancer metabolism drugs, has filed for an $86 million IPO. It plans to trade on the Nasdaq under ticker symbol AGIO, with J.P. Morgan and Goldman Sachs serving as lead underwriters. The company reports a $20 million net loss on $25 million in revenue for 2012. Shareholders include Third Rock Ventures (23.65% pre-IPO stake), Celgene (17.05%), ARCH Venture Partners (16.41%), Flagship Ventures (16.41%) and Fidelity (9.86%). www.agios.com

Gogo Inc. (f.k.a. Aircell), an Itasca, Ill.-based provider of WiFi access to airline passengers, has set its IPO terms to 11 million shares being offered at between $15 and $17 per share. It would have an initial market cap of approximately $1.38 billion, were it to price in the middle of its range. The company plans to list on the Nasdaq under ticker symbol GOGO, with Morgan Stanley, J.P. Morgan and UBS serving as co-lead underwriters. Shareholders include Ripplewood Holdings (38% pre-IPO stake) and Blumenstein/Thorne Information Partners (5.7%). Gogo reports a $32 million net loss on $233 million in revenue for 2012, compared to a $23 million net gain in 2011 on $160 million in revenue.www.gogo.com

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