Specialized Disclosure Report (Form SD)

Belden Inc.

Conflict Minerals Report

For The Year Ended December 31, 2025

This report for the year ended December 31, 2025 is presented to comply with Rule 13p-1 under the Securities Exchange Act of 1934 (the "Rule"). For the purpose of the required Reasonable Country of Origin Inquiry, Belden Inc. (the "Company") continued to receive supply chain responses through April 30, 2026. 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 "Act"). The Rule imposes certain reporting obligations on SEC registrants whose manufactured products contain conflict minerals which are necessary to the functionality or production of their products. Conflict minerals are defined as cassiterite, columbite-tantalite, gold, wolframite, and their derivatives, which are limited to tin, tantalum, tungsten, and gold ("3TG") for the purposes of this assessment. These requirements apply to registrants whatever the geographic origin of the conflict minerals and whether or not they fund armed conflict.

If a registrant can establish that the conflict minerals originated from sources other than the Democratic Republic of the Congo or an adjoining country (the "Covered Countries"), or from recycled and scrap sources, they must submit a Form SD which describes the Reasonable Country of Origin Inquiry completed.

If a registrant has reason to believe that any of the conflict minerals in their supply chain may have originated in the Covered Countries, or if they are unable to determine the country of origin of those conflict minerals, then the issuer must exercise due diligence on the conflict minerals' source and chain of custody. The registrant must annually submit a Conflict Minerals Report to the SEC that includes a description of those due diligence measures.

In compliance with the "Statement on the Effect of the Recent Court of Appeals Decision on the Conflict Minerals Rule" issued by the SEC's Division of Corporation Finance on April 29, 2014 and the judgment entered by the United States District Court for the District of Columbia on April 3, 2017, because this report does not state a conclusion that Belden's products are DRC conflict free, it has not been subjected to an independent private sector audit.

Forward Looking Statements

This Report contains forward-looking statements within the meaning of the federal securities laws. Any statements that do not relate to historical or current matters are forward-looking statements. You can identify some of the forward-looking statements by use of forward-looking words, such as "intend" and the like, or the use of future tense. Examples of forward-looking statements include, but are not limited to, statements concerning Belden's intended future efforts to mitigate the risk that the manufacture of its products benefits armed groups in the Covered Countries.