PRINCIPAL SECURITY HOLDERS

The following table sets forth information concerning those persons known to the Company to be the beneficial owners of more than 5% of the common stock of the Company.

Name and Address of Beneficial Owner Amount and Nature
Of Beneficial
Ownership
October 17, 2008
  Percent
of Class
NWQ Investment Management Co, LLC           1,335,3081               8.1
2049 Century Park East 16th Floor
Los Angeles, CA 90067

Kayne Anderson Rudnick Investment Management, LLC
  1,243,9442       7.5 %
1800 Avenue of the Stars
Second Floor
Los Angeles, CA 90067

Barclays Global Investors UK Holdings Limited
  1,038,0793       6.3 %
1 Churchill Place
Canary Wharf
London, England

Allianz Global Investors of America LP
  881,3304       5.3 %
680 Newport Center Dr. Suite 250
Newport Beach, CA 92660

Mario L. Crivello
  885,3865       5.4 %
San Diego, CA
  1. As of June 30, 2008, NWQ Investment Management Co., LLC (“NWQ”) filed a report on Form 13F with the Securities and Exchange Commission to report beneficial ownership of 1,335,308 shares. NWQ reported shared investment discretion with respect to all shares, shared voting authority with respect to 1,123,707 shares and no voting authority with respect to 211,601 shares. Beneficial ownership information as of October 17, 2008 is unavailable.
  2. As of June 30, 2008, Kayne Anderson Rudnick Investment Management LLC (“Kayne”) filed a report on Form 13F with the Securities and Exchange Commission to report beneficial ownership of 1,243,944 shares. Kayne reported sole investment discretion with respect to all shares, sole voting authority with respect to all shares. Beneficial ownership information as of October 17, 2008 is unavailable.
  3. As of June 30, 2008, Barclays Global Investors UK Holdings Limited (“Barclays”) filed a report on Form 13F with the Securities and Exchange Commission to report beneficial ownership of 1,038,079 shares. Barclays reported shared investment discretion with respect to all shares, sole voting authority with respect to 788,227 shares and no voting authority with respect to 249,852 shares. Beneficial ownership information as of October 17, 2008 is unavailable.
  4. As of June 30, 2008, Allianz Global Investors of America LP (“Allianz”) filed a report on Form 13F with the Securities and Exchange Commission to report beneficial ownership of 881,330 shares. Allianz reported shared investment discretion with respect to all shares, and sole voting authority with respect to all shares. Beneficial ownership information as of October 17, 2008 is unavailable.
  5. Mr. Crivello has sole voting and investment power over 751,701 shares held in trust for the benefit of others. He also has sole voting and investment power over 14,780 shares held as custodian for others and 102,363 shares held directly. Mr. Crivello also has the right to acquire 15,800 shares upon exercise of stock options and the right to receive 742 shares upon settlement of restricted stock units upon termination of his service as a director of the Company.