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EXHIBIT 21. LIST OF SUBSIDIARIES
Subsidiary Place of Organization
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MKS International, Inc. ........................... Massachusetts
MKS Instruments Deutschland GmbH .................. Germany
MKS Instruments France S.A. ....................... France
MKS Instruments Canada Ltd. ....................... Canada
MKS Instruments, U.K. Limited ..................... United Kingdom
MKS East, Inc. .................................... Massachusetts
MKS Japan, Inc. ................................... Japan
MKS Korea Co., Ltd. ............................... Korea
MKS FSC, Inc. ..................................... Barbados
D.I.P., Inc. ...................................... Ohio
MKS MCS, Inc. ..................................... Massachusetts
Compact Instrument Technology, LLC ................ Massachusetts
Spectra International, LLC ........................ California
Telvac Engineering Limited ........................ United Kingdom
