Benzinga's After Hours Decliners (CHK, MCO, RMBS, CSTR, APOL)

Among the notable names that are moving lower in the after hours trading session are Chesapeake Energy (NYSE: CHK), Moody's Corp. (NYSE: MCO), Rambus (NASDAQ: RMBS), Coinstar (NASDAQ: CSTR), and Apollo Group (NASDAQ: APOL).

Chesapeake Energy (CHK) has moved 3.12% lower to $20.50 in the late trading session on notable volume. More than 362,000 shares have exchanged hands since the close of the New York Stock Exchange. CHK had finished the regular session up 1.78% to $21.16.

Moody's (MCO) is getting hit hard after noted hedge fund manager David Einhorn told an audience at an investment conference that he is shorting the shares. MCO has fallen 5.41% to $19.75 in late trading.

Shares of technology name Rambus (RMBS) have been hammered in after hours trading, falling 9.40% to $22.55. During the regular market day, RMBS gained 3.06% to close at $24.89. Despite the strong showing, some traders were placing bearish options bets on the stock throughout the day. A press release stating that the International Trade Commission may take longer than planned to complete its investigation of a license agreement dispute between Rambus (RMBS) and Nvidia (NASDAQ: NVDA) and others may be catalyzing the after hours sell off. Rambus believes that NVDA and several other companies violated its technology patents.

Coinstar (CSTR) has fallen 4.17% in the after hours to $50.77 after the company lowered their Q2 and full year 2010 guidance. The company also announced that they have sold their E-Payment Services business to InComm.

Private Education name Apollo Group (APOL) has shed 4.96% to $50.75 in late trading. The activity in the name stems from a presentation that Steve Eisman made at the Ira Sohn Investment Research Conference today, the same event where David Einhorn offered up his short Moody's position. Eisman, who is the senior portfolio manager of the FrontPoint Financial Services Fund, said that he is shorting Apollo Group (APOL), and that the scandal in private education could rival that of the sub-prime mortgage crisis. You can find more on this story here.