Benzinga's M&A Chatter for Monday June 24, 2013

The following are the M&A deals, rumors and chatter circulating on Wall Street for Monday June 24, 2013: Tenet Healthcare to Acquire Vanguard Health Systems for $21/Share in Cash The Deal:
Tenet Healthcare THC and Vanguard Health Systems VHS announced Monday that they have agreed that Tenet will acquire Vanguard for $21 per share in cash. The deal is valued at $4.3 billion including the assumption of $2.5 billion in Vanguard debt and is expected to close before the end of 2013. Vanguard Health Systems closed at $20.70 Monday, a gain of 67% on 94 times average volume. Western Digital to Acquire STEC for $6.85/Share in Cash The Deal:
Western Digital WDC and STEC STEC announced Monday that they have agreed that STEC will be acquired by WDC subsidiary HGST, for approximately $340 million in cash, or $6.85 per share. The deal is expected to close in Q4 2013. STEC closed at $6.71 Monday, a gain of 87% on 49 times average volume. Keynote Signs Definitive Agreement to be Acquired by Thoma Bravo for $20/Share in Cash The Deal:
Keynote Systems KEYN announced Monday that it has agreed to be acquired by an affiliate of private equity firm Thoma Bravo $20.00 per share in cash or $395 million. The deal is expected to close before September 30, 2013. Keynote Systems, closed at $19.82 Monday, a gain of 46% on 44 times average volume.