NEW YORK, July 10 /PRNewswire-FirstCall/- Standard & Poor's will make the following changes to the S&P 500, S&P 100 and S&P SmallCap 600 indices:

-- MasterCard Inc. (NYSE: MA) will replace ACE Ltd. (NYSE: ACE) in the S&P 500, and MasterCard will replace General Motors Corp. (NYSE: GM) in the S&P 100 after the close of trading on Thursday, July 17. ACE is in the process of changing its place of incorporation to Switzerland, thus rendering it ineligible for inclusion in the S&P U.S. indices. General Motors will continue to be a member of the S&P 500.

-- Natus Medical Inc. (Nasdaq: BABY) will replace Chesapeake Corp. (NYSE: CSK) in the S&P SmallCap 600 after the close of trading on Tuesday, July 15. As of today's close of trading Chesapeake had a market value of approximately $32 million, whereas the minimum market cap a company must maintain in order to be eligible for addition to the index is currently $300 million.

Standard & Poor's will monitor these transactions, and post any relevant updates on its website: http://www.standardandpoors.com .

MasterCard specializes in transaction processing and brand licensing. Headquartered in Purchase, NY, the company will be added to the S&P 500 GICS (Global Industry Classification Standard) Data Processing & Outsourced Services Sub-Industry index.

Natus Medical provides healthcare products used for screening, detection, treatment, monitoring and tracking of common medical ailments. Headquartered in San Carlos, CA, the company will be added to the S&P SmallCap 600 GICS Health Care Equipment Sub-Industry index.

    Following is a summary of the changes:

                        S&P 500 INDEX -- July 17, 2008
                      COMPANY      GICS ECONOMIC SECTOR    GICS SUB-INDUSTRY
    ADDED           MasterCard   Information Technology     Data Processing &
                                                           Outsourced Services
    DELETED          ACE Ltd.       Financials             Property & Casualty
                                                                Insurance

                        S&P 100 INDEX -- July 17, 2008
                      COMPANY      GICS ECONOMIC SECTOR    GICS SUB-INDUSTRY
    ADDED           MasterCard    Information Technology    Data Processing &
                                                           Outsourced Services
    DELETED      General Motors    Consumer Discretionary     Automobile
                                                             Manufacturers

                   S&P SMALLCAP 600 INDEX -- July 15, 2008
                      COMPANY      GICS ECONOMIC SECTOR    GICS SUB-INDUSTRY
    ADDED          Natus Medical     Health Care        Health Care Equipment
    DELETED        Chesapeake         Materials             Paper Packaging

Additions to and deletions from an S&P equity index do not in any way reflect an opinion on the investment merits of the companies concerned.

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About Standard & Poor's

Standard & Poor's, a division of The McGraw-Hill Companies (NYSE: MHP), is the world's foremost provider of financial market intelligence, including independent credit ratings, indices, risk evaluation, investment research and data. With approximately 8,500 employees, including wholly owned affiliates, located in 21 countries. Standard & Poor's is an essential part of the world's financial infrastructure and has played a leading role for more than 140 years in providing investors with the independent benchmarks they need to feel more confident about their investment and financial decisions. For more information, visit http://www.standardandpoors.com .

SOURCE Standard & Poor's