Exhibit 1a
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-31636) of Mettler Toledo International, Inc., of our report dated June 19, 2012 with respect to the statements of net assets available for benefits (modified cash basis) of Mettler Toledo, Inc. Defined Contribution Retirement Plan as of December 31, 2011 and 2010, and the related statements of changes in net assets available for benefits (modified cash basis) for the years then ended, which report appears in the December 31, 2011 annual report on Form 11-K of Mettler Toledo, Inc. Defined Contribution Retirement Plan.
/s/ Clark, Schaefer, Hackett & Co.
Columbus, Ohio
June 19, 2012
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