UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM SD

Specialized Disclosure Report

ASCENDIS PHARMA A/S

(Exact name of registrant as specified in its charter)

Tuborg Boulevard 12

DK-2900 Hellerup

Denmark

(Address of principal executive offices)

Jan Møller Mikkelsen

President and Chief Executive Officer

Tuborg Boulevard 12

DK-2900 Hellerup, Denmark

Telephone: +45 70 22 22 44

(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

The Conflict Minerals Report of the registrant is filed as Exhibit 1.01 to this report on Form SD. The Conflict Minerals Report is available on our website on the SEC Filings page of the Investor Relations section of our website at https://investors.ascendispharma.com/. The content of any website referenced in this Form SD is included for general information only and is not incorporated by reference in this Form SD.

Item 1.02 Exhibit

See Item 1.01.

SECTION 2—EXHIBITS

Item 2.01—Exhibits

SIGNATURES

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

Exhibit 1.01

Ascendis Pharma A/S

Conflict Minerals Report

For The Calendar Year Ended December 31, 2023

This Conflict Minerals Report (the “Report”) for Ascendis Pharma A/S (“we,” “our” or “us”) is provided in accordance with Rule 13p-1 under the Securities Exchange Act of 1934 (“Rule 13p-1”) for the reporting period from January 1 to December 31, 2023. Rule 13p-1 requires the disclosure of certain information by companies that manufacture or contract to manufacture products that use minerals specified in Rule 13p-1 that are necessary to the functionality or production of these products. These minerals are columbite-tantalite (coltan), cassiterite, gold, wolframite, or their derivatives, which the Securities and Exchange Commission has limited to tantalum, tin, gold and tungsten (collectively, the “Minerals”).

We have determined that certain of the Minerals are necessary to the functionality of our TransCon^™ hGH auto-injector, a device which facilitates the administration of lonapegsomatropin by patients (the “hGH Device”).

All manufacturing of the hGH Device is contracted to be manufactured by one main supplier, who in turn has several layers of sub-suppliers. We do not have direct relationships with the sub-suppliers. In addition, due to the depth and complexity of the supply chain, we are far removed from the sources of ore from which these metals are produced and the smelters/refiners that process those ores. Consequently, we rely on our supplier and industry initiatives for source information on any Minerals contained in the hGH Device.

For the reporting period from January 1 to December 31, 2023, we conducted reasonable country of origin (“RCOI”) activities followed by due diligence investigations to determine the source and chain of custody of the Minerals that are necessary to the functionality or production of our products.

As of the date of this filing, the DRC-conflict areas include: the Democratic Republic of the Congo (referred to as “the DRC”), and/or adjoining countries of Angola, Burundi, Central African Republic, the Republic of the Congo, Rwanda, South Sudan, Tanzania, Uganda, and Zambia (collectively referred to as “the other covered countries”).

Based on the responses provided by our sub-suppliers, we cannot exclude the possibility that certain of these smelters and/or refiners may be sourcing Minerals from the DRC or the other covered countries.

Company Overview

Ascendis Pharma A/S is applying its innovative TransCon technology platform to build a leading, fully integrated biopharma company focused on making a meaningful difference in patients’ lives. We have created a portfolio of rare disease endocrinology product candidates to address unmet medical needs by utilizing our TransCon^™ technologies with clinically validated parent drugs. We currently have one product approved in the US (2021) and two in the EU (2022 and 2023). We have three product candidates in clinical development in rare endocrine diseases and two product candidates in clinical development in oncology.

Conflict Minerals Disclosure

Reasonable Country of Origin Inquiry (RCOI)

We have worked in close collaboration with our main supplier of the hGH Device to conduct a RCOI on its relevant suppliers (our sub-suppliers). Our supplier conducted a RCOI on relevant sub-suppliers supplying components to the hGH Device. Certain of the components identified for the hGH Device in turn may also contain various sub-components.

All of the contacted sub-suppliers responded, and certain of these sub-suppliers responded “yes” to the question of whether the respective component contained one or more of the designated Minerals. The majority of these sub-suppliers supplemented their response with the Responsible Minerals Initiative (the “RMI”) Conflict Minerals

Reporting Template, where they report on their usage and sourcing of materials containing the subject Minerals. The RMI Conflict Minerals Reporting Template was developed by several of the world’s leading consumer electronics companies and is generally regarded as the most common reporting tool for conflict minerals content and sourcing information.

Based on the RCOI, we believe that the sources of the Minerals necessary to the functionality of the hGH Device are from:

Design of Due Diligence Measures

Ascendis Pharma’s due diligence measures are inspired by the “OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas.” The following are the due diligence measures we performed on the source and chain of custody of the Minerals used in the hGH Device, and as a result of our RCOI:

1. Survey. Our supplier of the hGH Device conducted supply-chain surveys with its direct suppliers (our sub-suppliers). All sub-suppliers of the hGH Device who indicated that there are Minerals present in a component which they supply supplemented their response with a Conflict Minerals Reporting Template to identify the smelters and refiners and to determine the risks of any sources from the DRC-conflict areas within their supply chain. Sub-supplier responses were evaluated for plausibility, consistency and gaps, both in terms of which products were stated to contain or not contain the Minerals, and the origin of the Minerals. In addition, we validated the information received from our sub-suppliers to the extent possible.

2. Follow-up on Survey Responses. We followed-up with our supplier for the hGH Device on its suppliers surveyed, to the extent possible, on missing and inconsistent information.

3. Continual Investigation. We continually strive to identify risks within our supply chain. If any source is found to benefit armed groups in the DRC or other covered countries, we plan to work together with our primary supplier to remove such suppliers from our supply chain.

Location of Smelters and Refiners

As part of the due diligence process, we reviewed surveys from the sub-suppliers of the parts making up the hGH Device from our sub-suppliers of the hGH Device. Out of the responses received, certain sub-suppliers were deemed in scope of supplying components containing the subject Minerals. These sub-suppliers declared their smelter or refiner list, which listed several hundred possible smelters and refiners.

In each instance we were unable to identify the specific smelters which the Minerals used in the hGH Device were sourced from since the responses were company based and not product specific. We are unable to determine with certainty at this time a complete list of smelters and refiners listed in the surveys that actually provide the Minerals used in the hGH Device.

Country of Origin

Due to the use of company-wide surveys by some sub-suppliers and the multiple levels of suppliers in our supply chain we are unable to determine with certainty at this time a complete list of countries of origin listed in the surveys that provide the specific Minerals used in the hGH Device. Based on the responses provided, we believe the smelters and refiners supplying Minerals used in the hGH Device supply such Minerals that could originate from over 50 countries, including but not limited to, Angola, Belgium, Bolivia, Burundi, Brazil, Central African Republic, China, the DRC, Germany, India, Indonesia, Italy, Japan, Malaysia, Myanmar, Peru, Philippines, Poland, Rwanda, Singapore, South Africa, South Sudan, Spain, Switzerland, Taiwan, Tanzania, Thailand, Uganda United States of America, Vietnam and Zambia. Based on the responses provided, we cannot exclude the possibility that certain of these smelters may be sourcing Minerals used in the hGH Device from the DRC or other covered countries.

Steps to be taken to mitigate future risk

We intend to take the following steps to improve the program and further mitigate any risk that the necessary Minerals in the hGH Device could benefit armed groups in the DRC-conflict areas:

1. Third Party Compliance Approach. Since 2021, we have worked to further enhance our third-party compliance approach, including conflict minerals focus where relevant seeking inspiration from the Organization for Economic Cooperation and Development (OECD) Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas. We plan to continue this work in 2024.

2. Work with Suppliers on Documentation. In partnership with our suppliers, we plan to continue to communicate our expectations regarding required compliance documentation to be provided by our sub-suppliers. We also plan to continue to request that all our relevant sub-suppliers provide a completed and accurate RMI Conflict Minerals Reporting Template for the products or components that such sub-suppliers manufacture for us or our suppliers and that include covered Minerals.

Over time, we anticipate that the amount of information globally available regarding the traceability and sourcing of the Minerals used in our devices will increase.

FORWARD-LOOKING STATEMENTS

Statements that are not statements of historical fact, including statements relating to due diligence improvements and improvements of our conflict minerals focus, are forward-looking in nature and are based on our current expectations or beliefs. These forward-looking statements are not a guarantee of performance and are subject to a number of uncertainties and other factors that may be outside of our control and which could cause actual events to differ materially from those expressed or implied by the statements made herein. We do not intend, and expressly disclaim any obligation, to update such information for any changes in such factors or otherwise, except to the extent required by law.

DOCUMENTS INCORPORATED BY REFERENCE

Unless otherwise stated herein, any documents, third-party materials or references to websites (including our website) are not incorporated by reference in, or considered to be a part of this Report, unless expressly incorporated by reference herein.

INHERENT LIMITATIONS ON DUE DILIGENCE MEASURES

Our due diligence measures cannot provide absolute assurance regarding the source and chain of custody of the Minerals. Our due diligence processes are based on the necessity of seeking data from our direct supplier and that supplier seeking similar information within its supply chain to identify the original sources of the Minerals. Such sources of information may yield inaccurate or incomplete information and may be subject to fraud.