May 23, 2012, 6:30 PM UTC

China Investment Corp. is in talks to buy up to a $2 billion stake in Alibaba Group, according to Reuters. Alibaba would use the capital to buy back part of Yahoo’s position in the company.

SAP AG (NYSE: SAP) has agreed to acquire Ariba Inc. (Nasdaq: ARBA), a Sunnyvale, Calif.-based cloud-based business commerce network, for approximately $4.3 billion. The $45 per share offer represents nearly a 20% premium to Monday’s closing price for Ariba shares. www.sap.com

RailAmerica (NYSE: RA), a Jacksonville, Fla.-based short-line railroad operator majority-owned byFortress Investment Group, said that it is exploring strategic alternatives, including a possible sale.www.railamerica.com

Oracle has agreed to acquire Vitrue, a cloud-based social marketing and engagement platform. No financial terms were disclosed, although TechCrunch puts the sale price at $300 million. Virtrue had raised around $33 million from General Catalyst Partners, Comcast Ventures, turner Broadcasting, Advent Venture Partners, Scale Venture Partners and Dace Ventures. www.vitrue.com

PTT Exploration and Production of Thailand has agreed to acquire London-listed oil exploration company Cove Energy for £1.22 billion. Cove previously had accepted a £992 million takeover offer fromRoyal Dutch Shell.

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