Third Parties' Code of Business Conduct

Last Revised on December 2, 2025

Please direct all Questions on this Code of Conduct or on Ethical or Compliance Issues that arise to Integrity [at] hdrinc.com (Integrity[at]hdrinc[dot]com.)

To All HDR Vendors, Subcontractors, Suppliers, Joint Venture Partners, Advocates, and Agents:

Our HDR Corporate Code of Ethics sets forth how we conduct business and is based on these 11 principles:

Act with integrity.
Follow the law at all times and in all places.
Compete fairly and honestly.
Embrace diverse backgrounds and perspectives and treat people with dignity and respect.
Protect health, safety and the environment.
Avoid conflicts of interest.
Protect confidential information and our intellectual property.
Comply with government contracting rules.
Keep accurate financial books and records.
Comply with trade regulations.
Do not accept or make unlawful or inappropriate payments or gifts.

Our commitment to these principles is critical to serving clients and the long-term success of our company and our business partners. An ethical foundation is built upon trust in both HDR employees and our relationships with partners who share our commitment to sound business practices.

At HDR, we believe that doing the right thing for our clients and communities means acting ethically and honestly in all of our activities.

This HDR Third Parties’ Code of Business Conduct articulates our expectations of our partners and establishes minimum expectations for performance of agreements with HDR.

This Code of Conduct applies to all vendors with whom HDR conducts business except when the individual regional requirements mandate that a stand-alone Code of Conduct be issued; in such instances, the applicable Code of Conduct will be supplied to vendors performing work in those regions.

The Code is part of every contract you have with HDR. Thank you for sharing our commitment to doing business with integrity.

Sincerely,

John W. Henderson, Chief Executive Officer

Introduction

We expect HDR Third Party Partners to act in accordance with HDR’s principles set forth in this HDR Third Parties’ Code of Business Conduct (Code of Business Conduct).

This Code of Business Conduct applies to all HDR Third Party Partners who have not adopted a mandatory code of ethics or conduct generally consistent with this Code of Business Conduct.

HDR Third Party Partners that have a generally consistent code of ethics or conduct commit, by entering into an agreement with HDR, that they will comply with their code while working with and representing HDR.

Each Third Party Partner must confirm that all employees assigned to work with or to represent HDR have reviewed this Code of Business Conduct or their generally consistent code of ethics or conduct and that they will provide any lower tier subcontractors and subconsultants with access to this code or their code and require their compliance with that document.

Our third party vendors, subcontractors, suppliers, joint venture partners, agents, and advocates (HDR Third Party Partners) play a significant role in building and maintaining HDR’s world-class brand and reputation.

HDR Expects our HDR Third Party Partners to Comply with the Following Principles:

Act with Integrity

We expect HDR Third Party Partners to be honest and truthful in their dealings with us as we will be with them. We also expect our partners to scrupulously avoid undue influences and to comply with the requirements associated with their professional licenses and registrations.

Follow the Law at All Times

We expect HDR Third Party Partners to comply with all laws that apply to the work being performed, wherever that work is.

Sometimes, more than one set of laws will apply to a given opportunity or project;

in those instances, our partners are expected to comply with all applicable regulations from all jurisdictions and to ensure that any third parties with whom they are working do as well.

Compete Fairly and Honestly

HDR Third Party Partners shall not:

Promise, offer, or pay bribes for any reason;
Use the confidential information of others to gain improper advantage;
Propose or enter into any agreement with any competitor to fix prices, margins, or terms and conditions or to divide up any markets or customers; or
Make any false representations in connection with any HDR pursuit, proposal, or transaction including, but not limited to, misrepresentations of fact or the use of false or inaccurate records.
Lobby or retain lobbyists or agents to specifically advocate with government employees with respect to an HDR pursuit or project without the prior written permission of your HDR designated representative.

Embrace Diverse Backgrounds and Perspectives and Treat People with Dignity and Respect

HDR Third Party Partners shall provide equal opportunity and fair treatment for all without regard to ancestry, race, color, sex, sexual orientation, genetic information, religion, national origin, age, creed, veteran status, citizenship status, marital status, public assistance disability status, Vietnam Era Veteran status, recently separated, special disabled and other protected veterans or any other status protected by law.

Additionally, our partners shall not retaliate against any individual who makes a good faith allegation of wrong doing. Discrimination, harassment and retaliation will not be tolerated.

HDR Third Party Partners shall not use, either directly or indirectly, forced labor, unlawful child labor or labor from individuals who have been human trafficked.

Protect Health, Safety and the Environment

HDR Third Party Partners are accountable for making certain that their employees both understand the hazards to which their work may expose them and know how to prevent harm to themselves, to others and to their surroundings from such exposure. HDR Third Party Partners shall take all necessary measure to provide a safe working environment for their employees consistent with applicable law. HDR Third Party Partners are expected to take all reasonable precautions to protect the environment and to make choices that are resource sensitive.

Avoid Conflicts of Interest

HDR Third Party Partners must avoid any situation or relationship that may involve an inappropriate conflict or the appearance of a conflict with the interests of HDR or its other partners or clients. HDR Third Party Partners shall not offer or provide excessive gifts, hospitality or entertainment to any HDR employee or any family member of HDR employees or HDR’s other partners or clients. Any identified actual, potential, or apparent conflicts should be reported to HDR’s Conflict of Interest Manager at Integrity@ HDRInc.com or through HDR’s Integrity in Action Hotline at 888.847.5277 or online at Integrity in Action.

Protect Confidential Information and Intellectual Property

HDR Third Party Partners must use HDR’s and its clients’ confidential information, trade secrets, copyrights and other proprietary or personal information only in a manner that is permitted by law and under their contracts with HDR.

Such confidential information includes: any advertising, marketing, promoting, or other external communication or use of HDR’s name, brand, logo, or other trademarked or copyrighted content without the express prior written permission of HDR.

HDR Third Party Partners must not misuse, misappropriate, or infringe upon the trade information, trademarks, or copyrighted works of others, and must not misuse trade secrets or proprietary or confidential information of other third parties working with HDR for their own purposes or disclose such information to unauthorized third parties.

HDR acknowledges the transformative potential of generative artificial intelligence in our industry and communities. We embrace utilizing this technology responsibly and ethically.

HDR expects all Third Party Partners to act with integrity and comply with all applicable laws, regulations, standards, and contractual obligations with respect to data protection and generative artificial intelligence.

HDR Third Party Partners must notify HDR when they learn of or suspect any unauthorized use of HDR confidential information and must at all times protect and minimize the use and disclosure of personal data.

HDR Third Party Partners must not use HDR confidential information to train generative AI models and must not use generative AI output in any final work product for HDR without the prior written consent of HDR.

Comply With Government Contracting Rules

HDR Third Party Partners shall comply with all Government contracting rules applicable to the contract including any applicable timekeeping requirements, assigning fully qualified individuals to all projects, and only invoicing for expenses that are permitted and allowable under these contracts. Adherence to these requirements is subject to HDR and Government oversight and audit.

Keep Accurate Financial Books and Records

HDR Third Party Partners shall keep all financial books and records related to HDR projects accurately, completely and in accordance with their internal policies. Adherence to these requirements is subject to oversight and audit by HDR and the ultimate client.

Comply With Trade Regulations

HDR Third Party Partners must strictly comply with all export and import restrictions applicable to HDR contract activities and with sanctions applicable to the contract activities and as required by applicable laws. Business partners also need to be mindful of restrictions on doing business with certain countries, companies and individuals.

Do Not Accept or Make Unlawful or Inappropriate Payments or Gifts

HDR Third Party Partners must not offer, give, promise or authorize any bribe, gift, loan, fee, reward or other advantage to any government official or employee, any customer, any HDR employee or any other person to obtain any business advantage or improperly influence any action or decision. HDR business partners must comply with all applicable anti-corruption laws and regulations, including the U.S. Foreign Corrupt Practices Act and the UK Bribery Act.

Monitoring and Compliance

HDR may audit compliance with this Code of Conduct or appoint a third party to conduct an audit. Any violations will be reported to the HDR Third Party Partner’s management for their attention and, if appropriate, corrective action. HDR Third Party Partners shall cooperate or cause the cooperation of their employees and any second-tier third parties with respect to any HDR investigations into a potential violation of this Code of Conduct. Non-compliance with this Code of Conduct will negatively impact HDR’s ability to conduct business with your firm in the future.

HDR Third Party Partners and their employees and other stakeholders may report suspected violations of this Code of Conduct to HDR’s Conflict of Interest Manager at Integrity [at] HDRInc.com or through HDR’s Integrity in Action Hotline at 888.847.5277 or online at Integrity in Action.