The annual meeting of stockholders of ATMI, Inc. (the "Company") was held on May 23, 2012. As of March 27, 2012, the record date for the meeting, 33,111,971 shares of ATMI common stock were outstanding. A quorum consisting of 30,284,437 shares of common stock were present or represented at the meeting. The stockholders elected each of the Company's nominees for Class III director, approved the compensation of the Company's named executive officers on an advisory basis, and ratified the appointment of Ernst & Young LLP as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2012. The following tables represent the votes tabulated for each of these matters.

A.      Election of Class III Directors

                      For     Withheld  Broker Non-Votes
Stephen H. Mahle   27,974,867 1,073,449    1,236,121
C. Douglas Marsh   27,865,376 1,182,940    1,236,121

Douglas A. Neugold 28,450,730   597,586    1,236,121



B.      Advisory Vote to Approve Compensation of Named Executive Officers

For              27,949,070
Against             960,200
Abstain             139,046
Broker Non-Votes  1,236,121



C.      Ratification of Ernst & Young LLP

For     29,918,455
Against    357,394
Abstain      8,588