AT&T (NYSE: T) has agreed to acquire NextWave Wireless Inc., a license holder and manager of wireless spectrum interests in United States and Canada. The deal is valued at approximately $600 million in cash, including the assumption of debt.

OpenTable Inc. (Nasdaq: OPEN) has agreed to acquire Treat Technologies Inc., a New York–based provider of online gift card solutions for restaurants, for approximately $4 million in cash. Treat has raised VC funding from Granite Hill Capital Partners, Innovation Endeavors and Kima Ventures.

CF Industries Holdings Inc. (NYSE: CF) has agreed to acquire the interests in Canadian Fertilizers Ltd., owner of the largest nitrogen fertilizer complex in Canada, from Viterra Inc. (TSX: VT) for C$915 million in cash.

Synopsys Inc. (Nasdaq: SNPS) has agreed to acquire Taiwanese chipmaker Springsoft Inc. (TSEC: 2473) for $406 million, or $305 million net of cash acquired.

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