TENCOR INSTRUMENTS

FY: Dec 31 1996

Q: Sep 30 1996

Q: Aug 12 1996

Q: May 15 1996

5,7

5,7

Certification of termination of registration of a class of securities (Section 12(g))

Post Effective Amendment to S-8

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

SELIGMAN J & W & CO INC /NY/

SELIGMAN J & W & CO INC /NY/

PIONEERING MANAGEMENT CORP /ADV

FMR CORP

AMERICAN CENTURY COMPANIES INC

PIONEERING MANAGEMENT CORP /ADV

KLA INSTRUMENTS CORP

TENCOR INSTRUMENTS

TENCOR INSTRUMENTS

PIONEERING MANAGEMENT CORP /ADV

FMR CORP

TWENTIETH CENTURY COMPANIES INC

SELIGMAN J & W & CO INC /NY/