Oxford-based Sophos has acquired US cybersecurity firm SecureWorks in a $859m deal.

The transaction will make Sophos the largest pure-play Managed Detection and Response (MDR) provider, supporting more than 28,000 organizations.

US computing giant Dell, which controls around four-fifths of the share capital of the Nasdaq-listed business, had reportedly been seeking a private sale of SecureWorks for some time after a number of unsuccessful attempts at finding a buyer.

Dell will receive $8.50 per share in cash from the deal, which represents a 28% premium to the 90-day average share price.

Sophos CEO Joe Levy said: “With the integration of Secureworks, our expanded services and product portfolio will provide even stronger end-to-end security solutions that will include identity threat detection and response.

“We will also be able to further advance our AI, threat intelligence and attack research through more diverse and deeper global telemetry that is analyst-tuned for the real-world. At every level, we are very excited about this next accelerated chapter for Sophos.”

Abingdon-based Sophos was previously listed on the London Stock Exchange before being acquired by US private equity giant Thoma Bravo in a $3.9bn deal. Thoma Bravo has since added to its portfolio of British cybersecurity firms, after acquiring Darktrace last year in a $5.3bn deal.

In its most recent accounts, Sophos, which employs more than 600 staff, posted turnover of £644m for the year to end March 2024, a rise of 5.3% compared to the previous year, while profits nearly doubled to £189m.

Atlanta-based SecureWorks was founded in 1998 before being acquired by Dell in 2011.

Already have an account? Log in