November 22, 2011, 8:39 PM UTC

The Tokyo Stock Exchange has agreed to a $1.1 billion merger agreement with the Osaka Securities Exchange, which would create the world’s third-largest stock exchange.

Guardian Media Group is looking to sell PaidContent, a New York-based media news site and conference organizer it acquired three years ago, according to All Things D. Guardian reportedly is seeking between $15 million and $20 million, with Coady Diemar Partners managing the process.www.paidcontent.org

Hyundai Heavy Industries
 and Daewoo Shipbuilding & Marine Engineering each are considering €1 billion takeover offers for French engineering firm Gaztransport & Technigaz (GTT), according to Reuters.

Mexichem has offered to acquire Wavin, a listed Dutch maker of plastic piping. No terms of the offer were disclosed, but Wavin shares rose more than 60% on the news to close at a market cap of around €200 million.

Shanda Interactive (Nasdaq: SNDA) has agreed to be taken private by an investment group led by company CEO Tianqiao Chen. The deal would value Shanda, a Chinese Internet company, at around $2.3 billion.

Covidien (NYSE: COV) has agreed to acquire BarRx Medical Inc., a Sunnyvale, Calif.-based developer of endoscopic solutions for treating precancerous lesions of the esophagus. The deal is valued at around $325 million, plus the possibility of future earn-outs. BarRx has raised over $70 million in VC funding, from firms like Delphi Ventures, Alloy Ventures, Frazier Healthcare Ventures, Highland Capital Partners, Sutter Hill Ventures and Greenspring Associates. www.covidien.com
Ecova, a unit of Avista Corp. (NYSE: AVA), has agreed to acquire��Prenova Inc., an Atlanta-based enterprise energy management company. No financial terms were disclosed. Prenova has raised over $15 million in VC funding from firms like Arcapita Ventures, Austin Ventures, Siemens Venture Capital and River Cities Capital Funds. www.ecova.com

MatlinPatterson has agreed to sell XLHealth Corp., a sponsor of Medicare Advantage health plans with a primary focus on Medicare recipients with special needs, to a unit of UnitedHealth Group (NYSE:UNH). No pricing terms of the all-cash transaction were disclosed. MatlinPatterson acquired XLHealth back in 2007. www.xlhealth.com

Microsoft (Nasdaq: MSFT) has acquired VideoSurf, a San Mateo, Calif.-based online video search company, for around $70 million, according to multiple news reports. The company has raised around $28 million in VC funding from Pitango Venture Capital, Verizon Ventures and individual angels like Al Gore and Sheryl Sandberg. www.videosurf.com

Pfizer (NYSE: PFE) has agreed to acquire Excaliard Pharmaceuticals Inc., a Carlsbad, Calif.-based developer of drugs for the treatment of skin fibrosis (i.e., scarring). No financial terms were disclosed, except that the deal includes both an up-front payment and potential earn-outs. Excaliard has raised VC funding from Alta Partners, ProQuest Investments and RiverVest Venture Partners. www.pfizer.com

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