UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM SD

SPECIALIZED DISCLOSURE REPORT

STERIS plc

(Exact name of registrant as specified in its charter)

70 Sir John Rogerson’s Quay, Dublin 2, Ireland

DE21 6LY

(Address of principal executive offices)

J. Adam Zangerle

Registrant’s telephone number, including area code: + 353 1 232 2000

(Name and telephone number, including area code, of the person to contact in connection with this report.)

Check the appropriate box to indicate the rule pursuant to which this form is being filed, and provide the period to which the information in this form applies:

Section 1 – Conflict Minerals Disclosure

Item 1.01 Conflict Minerals Disclosure and Report

Conflict Minerals Disclosure

On March 28, 2019, STERIS plc, a public limited company organized under the laws of England and Wales (“STERIS UK”), completed a redomiciliation pursuant to which STERIS plc, a public limited company organized under the laws of Ireland (“STERIS plc”), became the ultimate holding company of STERIS UK and each of its existing subsidiaries. References in this Form SD to “the Company,” “us,” “we” or “STERIS” or any similar references relating to periods before the redomiciliation should be construed as references to STERIS UK unless the context requires otherwise, and references relating to periods from and after the date of the redomiciliation should be construed as references to STERIS plc.

This Form SD of STERIS plc is filed pursuant to Rule 13p-1 under the Securities Exchange Act of 1934, as amended, for the reporting period from January 1 through December 31, 2018.

We have evaluated our current product lines and determined that certain products we manufacture or contract to manufacture may contain tin, tungsten, tantalum and/or gold.

The brief description of our reasonable country of origin inquiry (“RCOI”) process, the results of our inquiry, and the determination we reached as a result of our RCOI process are included in our Conflict Minerals Report attached as an exhibit to this Form SD.

A copy of the Company’s Conflict Minerals Report is filed as Exhibit 1.01 hereto and is publicly available at: https://sterisplc.gcs-web.com/financials/sec-filings. The content of any website referred to in this Form SD is not incorporated by reference in this Form SD.

Item 1.02 Exhibit

A copy of the Company’s Conflict Minerals Report as required by Item 1.01 is filed as Exhibit 1.01 hereto.

Section 2 – Exhibits

Item 2.01 Exhibits

The following exhibit is filed as part of this report.

Exhibit 1.01 – Conflict Minerals Report as required by Items 1.01 and 1.02 of this Form.

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EXHIBIT INDEX

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the duly authorized undersigned.

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Exhibit 1.01

STERIS plc

Conflict Minerals Report for the Reporting Period from January 1, 2018 to December 31, 2018

Introduction

This Conflict Minerals Report is filed by STERIS plc (“STERIS”) for the reporting period from January 1, 2018 to December 31, 2018 (the “Reporting Period”) as Exhibit 1.01 to STERIS’s Form SD pursuant to the requirements of Rule 13p-1 of the Securities Exchange Act of 1934, as amended (the “Rule”), which was promulgated pursuant to the requirements of Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act. The Rule requires the annual filing with the Securities and Exchange Commission (“SEC”) of a Form SD, together with this Report (if relevant) as an Exhibit to Form SD, by STERIS regarding the sourcing of those conflict minerals (as defined below) contained in the products that STERIS and its subsidiaries (collectively, the “Company”) manufacture or contract to manufacture if the conflict minerals are necessary to the production or functionality of the products. Conflict minerals are defined as columbite-tantalite (also known as coltan, the metal ore from which tantalum is extracted), cassiterite (the metal ore from which tin is extracted), gold, and wolframite (the metal ore from which tungsten is extracted), or their derivatives, or any other mineral or its derivatives designated in specified circumstances by the U.S. Secretary of State to be financing conflict in the Democratic Republic of the Congo or an adjoining country (the “Covered Countries”). These conflict minerals are currently limited to tin, tantalum, tungsten and gold (“3TG” or “conflict minerals”).

As permitted by applicable guidance of the SEC, the Company has not obtained an independent private sector audit for this Conflict Minerals Report. The contents of any website referred to in this Conflict Minerals Report is not incorporated by reference in this Conflict Minerals Report.

The Company

The Company is a leading provider of infection prevention and other procedural products and services focused primarily on healthcare, pharmaceuticals, and research. Products manufactured or otherwise offered by the Company include the following: sterilizers, anti-bacterial wipes, generators and liquid chemical sterilant processing systems; automated washer/disinfector systems; general and specialty surgical tables; surgical and examination lights, operating room integration equipment including monitors, equipment management systems, warming cabinets, and other complementary products and accessories; high purity water equipment; operating room storage cabinets and scrub sinks; wound dressings and gastrointestinal endoscopy accessories and replacement parts; and cleaning chemistries and sterility assurance products and cleansing products. The Company also provides the following types of services: equipment installation and maintenance, microbial reduction of medical devices, instrument and scope repair solutions, laboratory testing services and on-site and off-site reprocessing.

Only certain STERIS products contain one or more 3TGs and fall in the scope of the Rule. We have determined that the following product lines contain or may contain 3TGs: sterilizers, generators and liquid chemical sterilant processing systems, automated washer/disinfector systems, general and specialty surgical tables, surgical and examination lights, warming cabinets, and high purity water equipment.

Company Supply Chains

The Company manufactures its products from components, raw materials and other materials purchased from third-party suppliers. These suppliers are located all over the world. The Company utilizes several different supply chains to support its manufacturing operations. In many cases there are numerous upstream layers involved in the Company supply chains, with the Company being a remote distance downstream from the smelter or refiner at which the conflict minerals are processed. We do not purchase any conflict minerals directly from miners, smelters or refiners. Therefore, we must rely on our direct and indirect suppliers to provide information about the origin of any conflict minerals in our products.

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Reasonable Country of Origin Inquiry (“RCOI”)

For reporting year 2018, our RCOI process utilized a risk-based approach to determine which of our suppliers we should survey for information regarding their conflict minerals sourcing. Our Senior Director of Internal Audit and Compliance, who reports directly to our Senior Vice President and Chief Compliance Officer, leads our conflict minerals compliance program. The Senior Director of Internal Audit and Compliance and a group of Company employees representing the compliance, supply chain, information technology and legal departments of the Company (the “Compliance Team”) reviewed and analyzed information about our products and supply chains to determine which product components and materials might be reasonably likely to contain necessary 3TGs. We based this determination on the nature of, and the suppliers of, the products and materials purchased. This focused, multi-variable analysis resulted in a refined list of suppliers that we determined potentially supplied us with products or materials containing 3TG (our “relevant suppliers”).

We engaged Assent Compliance, a third-party consultant (“Assent”), to assist with our RCOI, supplier engagement, and due diligence. We sent each of our relevant suppliers an introductory email describing our conflict minerals compliance program requirements and introducing them to Assent. Assent then engaged with those relevant suppliers and asked them to provide and/or update their RCOI information. We utilized the Conflict Minerals Reporting Template (“CMRT”) developed by the Conflict-Free Sourcing Initiative, now known as the Responsible Minerals Initiative (“RMI”) (revision 5.11 or higher) to conduct a survey of all in scope suppliers. We periodically reviewed the supplier list to determine whether there were any irrelevant or “out of scope” suppliers that should be removed from the survey process.

Assent requested that all suppliers complete a CMRT and offered online training and education intended to guide suppliers on best practices related to the use of the CMRT. All submitted forms were accepted and classified as valid or invalid so that all data was retained. We directly contacted suppliers that were unresponsive to Assent’s communications during the diligence process or claimed they were under no obligation to respond to us either because they were distributors or were located outside of the US or had been sold to non-US entities and requested such suppliers to complete the CMRT and submit it to Assent. In some cases, we made multiple follow-up requests to the same supplier. We continued to engage our suppliers throughout the entire RCOI process by providing feedback on smelters and refiners that suppliers named, reminders for any non-responsive suppliers, and detailed reasoning and recommendations for suppliers whose data did not meet Assent’s validity-check expectations. Assent compared the data obtained from our suppliers’ responses to information that had been collected and verified by third parties, including information from the RMI website and information in Assent’s database in order to determine the country of origin with the greatest possible specificity.

The Company accomplished an improvement in the number of responses from our suppliers over reporting year 2017. Specifically, the Company accomplished a 2% increase in the number of supplier responses for the reporting year 2018 over those for the reporting year 2017. Our suppliers identified 325 smelters and refiners. Based on the information available to us as a member of RMI, as of May 15, 2019, 45 of those smelters and refiners were reported to have some sourcing from the Covered Countries.

In the course of our RCOI, we were not able to definitively confirm the country of origin of all 3TGs that were contained in the materials or products that we purchased from our suppliers or to determine whether those 3TGs were from recycled or scrap sources. Therefore, we have concluded that some of our products manufactured during the reporting period contain necessary 3TGs that may have originated in the Covered Countries or may not be from recycled or scrap sources. Accordingly, we performed due diligence in an effort to determine the source and chain of custody of these necessary 3TGs.

Due Diligence

Design of Due Diligence Measures

The Company’s due diligence measures were designed to conform in all material respects with the due diligence framework in the Organisation for Economic Co-operation and Development (“OECD”) Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict–Affected and High-Risk Areas, and the related supplements for tin, tantalum, and tungsten and for gold, Third Edition, 2016 (“OECD Guidance”).

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Due Diligence Measures Performed

Due diligence measures performed for reporting year 2018 consisted of the following:

1. OECD Step #1: Establish and Maintain Strong Company Management Systems. The Company’s compliance department oversaw the Company’s conflict minerals compliance program. The Senior Director of Internal Audit and Compliance led the Compliance Team in its efforts to address and mitigate any conflict minerals-related risk and reported directly to STERIS’s Senior Vice President and Chief Compliance Officer. The Compliance Team advised our relevant suppliers of the existence of the STERIS Conflict Minerals Sourcing Policy (“Policy”), which is available to the public via STERIS’s website at https://www.steris.com/about/business/conflict_minerals_sourcing_policy.cfm, and directed them to the website to review it. The Policy advises suppliers that failure to comply with the policy may result in termination of the Company’s relationship with the non-compliant supplier.

The Compliance Team also supported our engagement with our direct suppliers about our Supplier Code of Conduct (“Supplier Code”) which was released during 2017. The Supplier Code prohibits suppliers from incorporating materials or parts in materials or services supplied to STERIS that would violate any law or regulation because of the origin of the material, part or service. The Supplier Code further provides that suppliers must have a policy to reasonably assure that the tantalum, tin, tungsten and gold in the products they manufacture do not directly or indirectly finance or benefit armed groups that are perpetrators of serious human rights abuses in the Covered Countries. The Supplier Code further provides that suppliers must exercise due diligence on the source and chain of custody of these materials and make the results of their due diligence measures available to STERIS upon request. The Supplier Code was released during 2017 and is available to the public via STERIS’s website at https://www.steris.com/about/business/supplier-code-of-conduct.cfm. Our Compliance Team provided periodic status reports to our Chief Compliance Officer and STERIS’s Board of Directors.

As part of the Company’s document retention policy, it is the Company’s policy to retain supplier responses and other communications and information relating to conflict minerals in electronic form for at least five (5) years.

During 2018, we emphasized supplier education and training relating to sourcing and information about the origin of conflict minerals. To accomplish this, we utilized Assent’s Learning Management System, Assent University, and provided all in-scope suppliers access to its Conflict Minerals training course at no cost.

The Company has grievance mechanisms whereby employees and suppliers can report concerns about the Company’s Policy and conflict minerals sourcing. Suppliers and other third parties may contact our conflict minerals team directly to communicate with us and may report grievances via our integrity helpline or webline, which are published in the STERIS Code of Business Conduct and the Supplier Code.

2. OECD Step #2: Identify and Assess Supply Chain Risk. We used a risk-based approach to identify our relevant suppliers for reporting year 2018. We identified those suppliers whose products were most likely to contain conflict minerals based on their commodity code within our materials planning system. We further refined our results by targeting those suppliers that represent a larger spend in order to maximize the impact of our survey efforts. On our behalf, Assent reviewed all responses received from our relevant suppliers and followed-up with them regarding incomplete responses and responses that appeared to be inaccurate. In addition, suppliers were contacted about the use of invalid forms and were encouraged to submit valid forms. Assent reviewed the lists of smelters and refiners provided by our suppliers and validated and cross-referenced that smelter and refiner information against information available through the RMI website. We provided information to our suppliers as to whether the smelters and refiners they listed were bona fide smelters or refiners and whether they had been audited and had a status of “conformant” with the Responsible Minerals Assurance Process (“RMAP”) or by RMAP-recognized programs (including the London Bullion Market Exchange Responsible Gold Programme, the Responsible Jewellery Council and the Tungsten Industry-Conflict Minerals Council), were active in such a process, were neither conformant nor active, or were not recognized as being a smelter or refiner.

For each facility that meets the RMI definition of a smelter or refiner of a 3TG, we assigned a risk rating of high, medium or low based on the following scoring criteria: geographic proximity to the Covered Countries, RMI audit status, and known or plausible evidence of unethical sourcing. In addition, we evaluated our suppliers on the strength of their conflict minerals programs as they were described in the suppliers’ CMRT responses. Based on that assignment of risk, we asked Assent to follow up directly with any supplier that identified certain smelters or refiners of the highest concern.

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3. OECD Step #3: Design and Implement a Strategy to Respond to Identified Risks. As noted above, our Compliance Team periodically briefed our Chief Compliance Officer and our Board of Directors about the Company’s conflict minerals compliance activities and results of our due diligence measures. Also as noted above, we followed-up with nonresponding suppliers and suppliers who provided incomplete responses or responses we believed to be inaccurate. We provided information to certain suppliers about the Rule and why we must obtain conflict minerals information from them.

As part of a strategy to respond to identified risks, we made those suppliers aware of our Conflict Minerals Sourcing Policy, the Supplier Code and the potential consequences to suppliers of noncompliance. Additionally, we notified all non-responsive suppliers that the Company has recorded the lack of response, that their future responsiveness will be monitored, and that we expect their responsiveness to future inquiries and the potential consequences for a lack of response in the future.

Based on our review of the list of smelters and refiners named by our suppliers, we identified certain facilities as being of highest concern to the supply chain and have followed up directly with any supplier that named these facilities in its CMRT. When our supplier responses included any of these high-risk facilities, Assent instructed that supplier to take certain risk mitigation actions, including submission of a product specific CMRT to better identify the connection to products that it supplies to STERIS and escalating up to removal of these high risk smelters from its supply chain. Suppliers are given clear performance objectives within reasonable timeframes with the ultimate goal of progressive elimination of these risks from the supply chain.

4. OECD Step #4: Carry Out Independent Third-Party Audit of Smelter/Refiner’s Due Diligence Practices. We do not have a direct relationship with smelters or refiners of conflict minerals. Therefore, we do not carry out audits of smelters or refiners identified by our suppliers as being in their supply chains. However, we support audits conducted by third-parties as a part of RMI of which we are a member (member code: STER).

5. OECD Step #5: Report Annually on Supply Chain Due Diligence. We report on our conflict minerals due diligence annually, and we make our Form SD and this Conflict Minerals Report publicly available on our website at www.steris.com/about/ir/sec.cfm.

Results of Due Diligence

Some of our suppliers provided us with names of smelters and refiners that may have processed the necessary 3TGs in their supply chains. Based on the information available to us as a member of RMI and from Assent’s database, many of the smelters and refiners named by our suppliers for calendar year 2018 that reported to RMI some sourcing from the Covered Countries were designated as RMI conformant. Based on the responses provided by our suppliers as reviewed against the data available to us as RMI members and against Assent’s database, all as of May 15, 2019, we have concluded that some of the tin, tantalum, tungsten and gold contained in our products may have originated in the countries listed below.

1. Facilities Used to Process Necessary Conflict Minerals.

As a result of our due diligence, we obtained information from some of our suppliers about the smelters and refiners that processed the necessary conflict minerals in their supply chains. We reviewed our suppliers’ responses and compared the names of the smelters and refiners they disclosed to the information included on the RMI website. Because most of our suppliers provided company-level CMRTs, we were unable to determine whether any particular smelters or refiners named in their responses actually processed the necessary 3TGs in our products. However, based on our review of our suppliers’ responses, we believe that the facilities that may have been used to process the 3TGs contained in our products include, but may not be limited to, the smelters and refiners listed in Appendix A. Because most of our suppliers provided company-level CMRTs, it is likely that this list includes more facilities than those that actually processed the minerals contained in our products.

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Based on the information provided by our suppliers in their CMRT responses, we believe that the facilities that may have been used to process the 3TGs in our products may include the smelters and refiners listed in Appendix A. Our supplier responses included conformant and active smelters and refiners and others that were unknown or that were not participating in the RMAP process. Only the conformant and active smelters and refiners, as well as other facilities verified as smelters or refiners based on the information available to us from Assent, have been listed in Appendix A.

2. Countries of Origin of Our Necessary Conflict Minerals.

Assent reviewed the lists of smelters and refiners provided by our direct suppliers and validated and cross-referenced that information against information available through the RMI website and Assent’s database. Based on this information, our suppliers’ responses and that information available to us as a member of RMI, as of May 15, 2019, the possible countries of origin of the necessary conflict minerals in our products include, but may not be limited to, the following:

Table 1

Possible Countries of Origin – Tin

Table 2

Possible Countries of Origin – Tantalum

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Table 3

Possible Countries of Origin – Tungsten

Table 4

Possible Countries of Origin – Gold

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3. Efforts to Determine Mine or Location of Origin.

We have determined that the most reasonable effort we can make to determine the mines or locations of origin of our necessary conflict minerals to the greatest possible specificity is to seek information from our direct suppliers about the smelters and refiners and the countries of origin of the necessary conflict minerals in our supply chain and to ask our suppliers to make the same inquiries from their suppliers. As noted above, upon receipt of supplier-provided data, we utilized our RMI membership and relationship with Assent to determine the possible countries of origin by cross-referencing the data against RMI’s lists of recognized conformant smelters and refiners and against Assent’s database.

Steps Taken and Being Taken to Mitigate Risk and Improve Due Diligence

In reporting year 2018, the Company further strengthened its internal management system by merging the compliance department with the internal audit department to lead the Compliance Team in its efforts to address and mitigate any conflict minerals-related sourcing risk. The Company expanded the number of STERIS business units whose suppliers were requested to provide sourcing information about the conflict minerals contained in the products they sold to us. The Company has continued working with Assent on our RCOI and due diligence process. We have increased our follow-up efforts to obtain more complete information from our suppliers regarding countries of origin, smelters and refiners. These efforts have increased the number of validated responses received. We intend to continue and increase these follow up efforts in the next reporting year. Currently, we also expect to continue providing additional background and educational information to suppliers where necessary to facilitate obtaining responses. STERIS currently expects to continue to fund and participate in the RMI which reduces conflict minerals risk for all supply chains by working to increase the number of smelters and refiners whose due diligence practices meet the Responsible Mineral Assessment Protocols.

Forward-Looking Statements

Certain statements contained in this Report, including those made under the “Steps Taken and Being Taken to Mitigate Risk and Improve Due Diligence” section, reflect the Company’s expectations with respect to future performance and constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements include, among other things, statements of the plans and objectives of management for future operations. These statements are subject to a variety of uncertainties, unknown risks and other factors concerning the Company’s operations and business environment, which are difficult to predict and are beyond the control of the Company.

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APPENDIX A

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