Standard & Poor's will add Cintas (CTAS) - Get Report to the S&P 500 index after the close of trading Wednesday, to replace the vacancy created by FleetBoston's acquisition of Summit Bancorp (SUB) - Get Report.

FleetBoston is already a member of the S&P 500.

Cintas, a component of the

S&P MidCap 400

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, will be replaced in that index by

Newport

(NEWP)

. Cintas designs uniforms that it rents or sells to customers in the U.S. and Canada. Newport supplies components, instruments and other products to fiber-optic communications companies and semiconductor equipment providers.