UPDATE 1-Ex-CFO, friends charged with insider trading

* Ex-CFO, friends accused of making $8 million improperly

* SEC says they traded on non-public earnings information

(Adds details from complaint)

WASHINGTON, Oct 30 (Reuters) - U.S. securities regulators charged the former executive of a private investment firm and six of his relatives and friends on Friday with insider trading in the securities of Tempur-Pedic International Inc (TPX.N) and Acxiom Corp (ACXM.O).

The Securities and Exchange Commission alleges that Chen Tang, the former CFO of a private equity fund, his friends and relatives reaped more than $8 million from using nonpublic material information to trade Tempur-Pedic and Acxiom.

The private equity fund was not named in the complaint.

In 2008, Tang found out about a surprise announcement that Tempur would not meet its earnings forecast, the SEC alleged.

Tang then tipped three of his friends with that information and the four of them started establishing short positions in Tempur, regulators said. The positions paid off when the company's stock dropped 37 percent after the announcement.

The SEC also alleged that Tang received a tip from his brother-in-law about a pending bid for Acxiom and then later that the deal was in jeopardy. Tang then tipped his friends and his brother, who collectively realized profits of more than $6 million, according to regulators.

Calls to Tang's lawyer were not immediately returned. (Reporting by Rachelle Younglai, editing by Gerald E. McCormick)