Carlyle Group LP agreed to buy Symantec Corp.’s Veritas data-storage unit for $8 billion in the biggest U.S. leveraged buyout this year.

Equity for the deal will primarily come from Carlyle’s U.S. buyout fund and GIC, Singapore’s sovereign wealth fund, Washington-based Carlyle said in a statement Tuesday. The transaction is expected to be completed at year-end.

Carlyle and Mountain View, California-based Symantec negotiated terms for months, and the deal is the first major buyout to be done from the private equity firm’s newly reopened Silicon Valley office.

In a year when private equity dealmakers including Carlyle’s Bill Conway have lamented high prices for companies, the transaction is the biggest U.S. leveraged buyout announced in 2015, surpassing the $5.3 billion LBO of software company Informatica Corp. announced in April, according to data compiled by Bloomberg.

Bill Coleman, the founder of software company BEA Systems Inc., will become Veritas’s chief executive officer, the companies said. Bill Krause, a Carlyle operating executive who previously was president and CEO of 3Com, will be chairman.

The Veritas sale will provide cash for Symantec, which has seen its dominance of the cyber-security business eroded as hackers have found ways to thwart its key security product, antivirus software. Symantec needs the cash to fund acquisitions and build costly security services such as incident response, Daniel Ives, an analyst at FBR Capital Markets & Co. in New York, said in an interview.

“There have been some glimmers of positive news about product refreshes and some of what they’ve done around cost cutting, but the growth issues they have here are massive,” said Ives, who rates the stock market perform. “They’ve been really on the wrong side of spending in terms of cyber- security.”

For the quarter ended in June, Symantec said sales fell 14 percent to $1.5 billion, missing the $1.53 billion average estimate of analysts surveyed by Bloomberg. Adjusted profit of 40 cents a share compared with the 43-cent average expectation.

Symantec fell 2.4 percent to $22.35 at 9:40 a.m. in New York, extending its decline this year to 13 percent.

A sale of Veritas, bought in 2005 for more than $13 billion, is symbolic of Symantec’s refocusing on the security market as it tries to lessen its dependence on antivirus. As part of the effort, Symantec earlier this year said it was hiring 65 engineers and data scientists from Boeing Co.’s Narus security division, which makes network-monitoring technologies used by the U.S. government.

Carlyle, founded in 1987 by Conway, Dan D’Aniello and David Rubenstein, has snapped up corporate orphans since it started buying defense companies in the aftermath of the fall of the Berlin Wall. So-called carve-outs were once the bread-and-butter of the leveraged buyout business as practitioners such as Carlyle, Blackstone Group LP and Clayton Dubilier & Rice persuaded boards of directors to sell a struggling unit or a business that didn’t fit into a corporation’s strategic direction.

“Our significant experience investing in software businesses, as well as our extensive experience with carve-out transactions, positions us well,” said Cam Dyer, a managing director in Carlyle’s telecommunications, media and technology group.

Carlyle manages $193 billion in private equity, real estate, credit and hedge fund assets. The firm said it’s invested $18 billion of equity in 243 telecom, media and tech companies such as SS&C Technologies Holdings Inc., Dealogic and Syniverse Holdings Inc.