Thoma Bravo buys cybersecurity vendor Proofpoint for $12.3B in cash

Moree M&A activity underway in the red-hot field of cybersecurity. In the latest development, private equity giant Thoma Bravo is buying Proofpoint, the SaaS security vendor, for $12.3 billion in cash. Proofpoint is traded publicly on the Nasdaq exchange and as of its closing price on Friday, i…