Specialized Disclosure Report (Form SD)

Entegris, Inc.

Conflict Minerals Report

For the reporting period from January 1, 2025 to December 31, 2025

Introduction

This Conflict Minerals Report (this "Report") of Entegris, Inc. (herein referred to as the "Company", "we", "us", or "our") has been prepared pursuant to Rule 13p-1 and Form SD (the "Rule") promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), for the reporting period from January 1, 2025 to December 31, 2025.

The Rule was adopted by the Securities and Exchange Commission (the "SEC") to implement reporting and disclosure requirements related to conflict minerals as directed by the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010.

The Rule requires disclosure of certain information when a company manufactures or contracts to manufacture products and the minerals specified in the Rule are necessary to the functionality or production of those products. "Conflict Minerals" are defined as cassiterite, columbite-tantalite (coltan), wolframite, gold and their derivatives, which are limited to tin, tantalum, tungsten, and gold ("Conflict Minerals" or "3TG"). These requirements apply to registrants whatever the geographic origin of the Conflict Minerals and whether or not they fund armed conflict. The "Covered Countries" for the purposes of the Rule and this Report are the Democratic Republic of the Congo, the Republic of the Congo, the Central African Republic, South Sudan, Uganda, Rwanda, Burundi, Tanzania, Zambia and Angola.

If any 3TGs are necessary to the functionality or production of a product manufactured by the registrant or contracted by the registrant to be manufactured, the registrant must conduct in good faith a reasonable country of origin inquiry ("RCOI") regarding the sourcing of those 3TGs that is reasonably designed to determine whether any of the 3TGs originated in the Covered Countries or are from recycled or scrap sources.

Based on its RCOI, if the registrant knows or has reason to believe that any of its necessary 3TGs originated in the Covered Countries and are not from recycled or scrap sources, the registrant must exercise due diligence on the source and chain of custody of its 3TGs that conforms to a nationally or internationally recognized due diligence framework. If, as a result of that due diligence, the registrant is unable to determine that its 3TGs did not originate in the Covered Countries or the registrant determines that its 3TGs did come from recycled or scrap sources, the registrant must perform due diligence on the source and chain of custody of those 3TGs and disclose that information in a conflict minerals report filed as an exhibit to its Form SD.

Consistent with guidance from the SEC, this Report has not been the subject of an independent public sector audit.