Symantec has agreed to sell its data-management business Veritas to the Carlyle Group private-equity firm for $8 billion in cash, a long anticipated move that will deliver cash to shareholders, but which represents a markdown from Symantec's all-stock purchase of Veritas for $13.5 billion in 2005.

Other investors, including Singapore's sovereign wealth fund, will join Carlyle in the acquisition, which is expected to close by the end of this year. Symantec previously announced plans to spin off Veritas in October.

Founded in 1983 as Tolerant Systems, Veritas initially focused on data backup and recovery. Following the merger with Symantec, the firm has increased its focus on data management.

The planned sale comes as a general mania for spinoffs pervades Silicon Valley, with eBay, HP, and JDSU all planning or recently completing splits. So far this year, spinoffs have returned $50 billion in shares to shareholders, The Wall Street Journal reports.

In announcing the deal on Tuesday, Symantec emphasized the benefits to shareholders in the form of stock buybacks and dividends, saying that it plans to increase its buyback program by at least $3.5 billion over the next two years.

Symantec shares were down as much as 5 percent in midday trading Tuesday.