Hanger Inc. will join the S&P SmallCap 600 Index, replacing semiconductor equipment company Rudolph Technologies Inc., effective before trading on Oct. 28.

Austin, Texas-based Hanger provides orthotic and prosthetic services. The company will join the S&P SmallCap 600 Global Industry Classification Standard Health Care Facilities Sub-Industry index.

Wilmington, Mass.-based Rudolph Technologies is being acquired by Nanometrics Inc.

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