O'Reilly Successfully Completes Exchange Offer for CSK, Over 90% Tendered

Jul 11, 2008

Springfield, MO – July 11, 2008 — O'Reilly Automotive, Inc. (“O'Reilly”) (Nasdaq: ORLY) today announced that its indirect, wholly-owned subsidiary has accepted, for payment and exchange, all shares validly tendered pursuant to its offer for all outstanding shares of common stock of CSK Auto Corporation (“CSK”) (NYSE: CAO). Each share of CSK common stock validly tendered and not withdrawn was exchanged for 0.4285 of a share of O'Reilly common stock plus $1.00 in cash.