Tech stock have languished so far in 2021, which has created golden opportunities for mergers and acquisitions by strategic and financial buyers, according to Ives. "We view the Microsoft/Nuance marriage and now the Proofpoint deal as just the tip of the iceberg around a broader M&A spree in the tech landscape for the remainder of 2021," Ives said. After a monster 2020 in which seven cybersecurity vendors at least doubled their valuations, 2021 is off to a slower start, with only Fortinet and McAfee (along the 10 most valuable cybersecurity companies) growing their stock price by more than 15 percent so far this year. Proofpoint had been treading water, with the company's stock price down 0.7 percent in 2021 prior to the Thoma Bravo deal announcement.