LONDON — British cybersecurity firm Darktrace on Friday announced it had agreed a sale to U.S. private equity giant Thoma Bravo, for an all-cash offer of $5.315 billion.

Darktrace shares were 17% higher at 10:26 a.m. London time.

Investors are set to receive $7.75 in cash for each share held, under the terms recommended by the board.

Its move private will be seen as a major blow to the London Stock Exchange, where it listed in 2021. The company was seen as a welcome dynamic addition to a market often characterized as less appealing to technology firms than those in the U.S. or Asia, and stacked with "old economy" players, such as miners and oil and gas companies.

Darktrace specifically referenced its belief that it is undervalued in the U.K. as a reason for the sale. In a statement, it said its board believes the firm's operational and financial "achievements" are not reflected in its valuation and that shares are trading "at a significant discount to its global peer group."

Darktrace was founded in 2013 and is based in the U.K. city of Cambridge, which has attracted a cluster of tech firms over the last decade. It specializes in artificial intelligence-based protection against cloud attacks for large companies and events, and has roughly 2,300 employees based worldwide.

Thoma Bravo said the acquisition would increase its exposure to the large and growing cybersecurity market, and that its investment in Darktrace would help scale the business globally.

The deal represents a 44.3% premium to the average volume-weighted Darktrace share price in the three months to April 25, according to the release.

Darktrace on Friday said it had rejected previous unsolicited proposed offers from Thoma Bravo because the tech company assessed they did not fairly value the business.

The company has faced several challenges since its listing, including a short-selling attack in 2023, which led it to defend its accounting practices. It has also sought to distance itself from co-founding investor Mike Lynch, who faces fraud charges in the U.S.