Barracuda Networks has been acquired by private equity giant Thoma Bravo in a deal worth $1.6bn (£1.2bn).
The New York-listed security vendor went public in 2013, but will now join a portfolio of vendors that includes Riverbed and Solar Winds.
The all-cash transaction will see shareholders receive $27.55 for each share. Barracuda's share price reached its all-time high in April 2015, before dipping to a low of $10.41 in January 2016.
Speaking of the acquisition, Barracuda CEO BJ Jenkins said: "We believe the proposed transaction offers an opportunity for us to accelerate our growth with our industry-leading security platform that's purpose-built for highly distributed, diverse cloud and hybrid environments.
"Thoma Bravo has an excellent history of investing in growing security businesses, and this transaction speaks to the value and strength of Barracuda's security platform, which helps customers protect and manage their networks, applications, and data.
"We will continue Barracuda's tradition of delivering easy-to-use, full-featured solutions that can be deployed in the way that makes sense for our customers."
The transaction is expected to close before the end of Barracuda's fiscal year on 28 February.
Dan Bailey, director of Barracuda's only UK Premier partner, said he expected Barracuda to be acquired at some stage because of its relatively low share price, adding that a private equity buyer means its product portfolio won't be tampered with in a way it might have been if its acquirer were another vendor.
"They were very undervalued given the technology they've got and the product portfolio, so I'm not surprised [they've been acquired]," he said.
"I don't really think there's a preference between private equity and another vendor. The good thing about their being acquired by private equity is that their portfolio won't be diluted into the portfolio of Symantec, for example."
Bailey said he is not concerned that Thoma Bravo will interfere with Barracuda's day-to-day activity, claiming he expects the vendor's rate of innovation to improve, if anything.
He explained that working with Barracuda became slightly more laborious when it listed in 2013 as a result of the red tape that comes with going public.
"One of the limiting factors of them being a public company was that every decision was a little bit slower than it is if you're a private company and there's a bit more scrutiny on any activity that money is spent on," he said.
"We were partners with them before they filed for their IPO, and after the IPO it was probably a more corporate and strict environment in terms of how we could partner with Barracuda to go out and win more customers.
"We still got things done but it was probably a bit slower, so we're very excited about the next couple of years now."
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