SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 4)* KLA -Tencor Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 482480100 (CUSIP Number) December 29, 2000 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: [X] Rule 13d-1(b) [ ] Rule 13d-1(c) [ ] Rule 13d-1(d) *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). 1 NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Capital Group International, Inc. 95-4154357 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) (b) 3 SEC USE ONLY 4 CITIZENSHIP OR PLACE OF ORGANIZATION California 5 SOLE VOTING POWER 12,914,150 6 SHARED VOTING POWER NUMBER OF SHARES NONE BENEFICIALL Y OWNED BY 7 SOLE DISPOSITIVE POWER EACH REPORTING 14,712,550 PERSON WITH: 8 SHARED DISPOSITIVE POWER NONE 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 14,712,550 Beneficial ownership disclaimed pursuant to Rule 13d-4 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 7.9% 12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) HC SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 Schedule 13G Under the Securities Exchange Act of 1934 Amendment No. 4 Item 1(a) Name of issuer: KLA -Tencor Corporation Item 1(b) Address of issuer's principal executive offices: 160 Rio Robles San Jose, CA 95134 Item 2(a) Name of person(s) filing: Capital Group International, Inc. Item 2(b) Address or principal business office or, if none, residence: 11100 Santa Monica Blvd. Los Angeles, CA 90025 Item 2(c) Citizenship: N/A Item 2(d) Title of class of securities: Common Stock Item 2(e) CUSIP No.: 482480100 Item 3 If this statement is filed pursuant to sections 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filings is a: (g) [X] A parent holding company or control person in accordance with section 240.13d-1(b)(1)(ii)(G). Item 4 Ownership Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1. See page 2 (a) Amount beneficially owned: (b) Percent of class: (c) Number of shares as to which the person has: (i) Sole power to vote or to direct the vote: (ii) Shared power to vote or to direct the vote: (iii) Sole power to dispose or to direct the disposition of: (iv) Shared power to dispose or to direct the disposition of: CUSIP: 482480100 Page 3 of 5 Capital Group International, Inc. is the parent holding company of a group of investment management companies that hold investment power and, in some cases, voting power over the securities reported in this Schedule 13G. The investment management companies, which include a "bank" as defined in Section 3(a)6 of the Securities Exchange Act of 1934 (the "Act") and several investment advisers registered under Section 203 of the Investment Advisers Act of 1940, provide investment advisory and management services for their respective clients which include registered investment companies and institutional accounts. Capital Group International, Inc. does not have investment power or voting power over any of the securities reported herein; however, Capital Group International, Inc. may be deemed to "beneficially own" such securities by virtue of Rule 13d-3 under the Act. Item 5 Ownership of 5 percent or Less of a Class. If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following: [ ] Item 6 Ownership of More than 5% on Behalf of Another Person: N/A Item 7 Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person. 1. Capital Guardian Trust Company is a bank as defined in Section 3(a)(6) of the Act and a wholly owned subsidiary of Capital Group International, Inc. 2. Capital International Limited (CIL) does not fall within any of the categories described in Rule 13d-1-(b)(ii)(A-F) but its holdings of any reported securities come within the five percent limitation as set forth in a December 15, 1986 no-action letter from the Staff of the Securities and Exchange Commission to The Capital Group Companies, Inc. CIL is a wholly owned subsidiary of Capital Group International, Inc. 3. Capital International S.A. (CISA) does not fall within any of the categories described in Rule 13d-1-(b)(ii)(A-F) but its holdings of any reported securities come within the five percent limitation as set forth in a December 15, 1986 no-action letter from the Staff of the Securities and Exchange Commission to The Capital Group Companies, Inc. CISA is a wholly owned subsidiary of Capital Group International, Inc. 4. Capital International Research and Management, Inc. dba Capital International, Inc. is an investment adviser registered under Section 203 of the Investment Advisers Act of 1940 and is a wholly owned subsidiary of Capital Group International, Inc. Item 8 Identification and Classification of Members of the Group: N/A CUSIP: 482480100 Page 4 of 5