UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Table of Contents FORM 10-Q (Mark one) x QUARTERLY REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 000-09992 KLA-Tencor Corporation (Exact name of registrant as specified in its charter) Delaware 04-2564110 (State ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark one) x QUARTERLY REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended December 31, 2018 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 000-09992 KLA-Tencor Corporation (Exact name of registrant as specified in its charter) | Delaware | | --- | | ...