Exhibit 10.43

July 29, 2008

Mark Dentinger

[address]

Dear Mark:

I am pleased to offer you the opportunity and challenge to join the KLA-Tencor team. As Executive Vice President and Chief Financial Officer, you will work under my direction. The details of your employment offer are as follows:

SALARY: $15,384.62 bi-weekly, equivalent to $400,000.00 annually.

FLSA STATUS: Exempt

RESTRICTED STOCK UNITS: It will be recommended at the next Board of Directors’ Compensation Committee meeting, pursuant to the Company Stock Option Plan, that you be granted 40,000 restricted stock units (RSUs) of KLA-Tencor stock per the company’s normal vesting schedule.

ANNUAL INCENTIVE BONUS: You are eligible to receive an annual incentive bonus based on a bonus target of 75% of your paid base salary. Any bonus payments to be made will be paid once per year and you must be an eligible employee on the date of payout to receive this incentive bonus. Please see the Annual Incentive Bonus Plan document for specific details.

EXECUTIVE SEVERANCE PLAN: You will participate in the company’s Executive Severance Plan at the same level of protection as the company’s General Counsel.

FOCAL REVIEW PROGRAM: Employee performance is measured and evaluated based on KLA-Tencor’s fiscal year.

The Immigration Law, effective November 6, 1986, requires that all employers verify each individual’s eligibility to work in the United States, including U.S. citizens. Your employment offer is contingent upon your providing satisfactory proof of identity and authorization to work in the United States. Please bring the appropriate regional documentation on your first day of work. In addition, the U.S. Export Administration Regulations restrict the transfer of certain technology out of the U.S., as well as the release of certain technology to foreign persons, even if they are in the U.S. This offer of employment is contingent upon receipt of export approval from the U.S. Department of Commerce, if required.

Mark, I am convinced that you will be an extremely valuable asset to KLA-Tencor and hope you will find many opportunities to grow both professionally and personally.

This offer is contingent upon completion of a Director and Officer questionnaire and a satisfactory background and reference check, and it will expire on August 6, 2008. To indicate acceptance of this employment offer, please sign both copies of this letter an