Seche Environnement : APPROVAL OF ALL RESOLUTIONS AVAILABILITY OF THE MEETING MINUTES EVOLUTION OF GOVERNANCE

Changé, France; April 28, 2023

PRESS RELEASE

JOINT GENERAL MEETING OF APRIL 28, 2023

APPROVAL OF ALL RESOLUTIONS

AVAILABILITY OF THE MEETING MINUTES

EVOLUTION OF GOVERNANCE

The Joint General Meeting took place today from 10 am to 11 am at the registered office of the Company in Changé, with shareholders present or represented totaling 81.28% of the capital shares and 76.65% of the voting rights.

The Bureau was composed as follows:

• Chairman: Mr. Joël Séché, Chairman of the Board of Directors
• Scrutineers:
• • The FCPE1 Séché Croissance represented by Mr. Manuel Andersen, Chairman of the Supervisory Board of the FCPE Séché Croissance.
  • Mr. Jean-PierreVallée-Lambert
• Secretary: Mr. Neil Curtis, Group General Counsel

Messrs. Maxime Séché, Chief Executive Officer and Baptiste Janiaud, Chief Administrative and Financial Officer, commented on the main elements of activity and results for FY22, as well as recent developments, the activity as of March 31, 2023, and the outlook for activity and results for the current year.

The Chairman noted that no written question had been put to the Board of Directors and then passed the floor to the shareholders present at the Meeting for a session of oral questions. No questions were asked by the attendance.

The President proceeded to the vote on the resolutions.

All proposed resolutions were approved, including those on the accounts and allocation of 2022 earnings.

In particular, the Assembly approved the distribution of a dividend of €1.10 versus €1.00 for fiscal year 2021.

The Assembly also approved the appointments of Mr. Guillaume Cadiou and Ms. Anne-Brigitte Spitzbarth and Ms. Nathalie Tarnaud Laude as Independent Directors.

• Employee Mutual Fund

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Press release - April 28, 2023

The Board of Directors is now composed of 7 Members, assisted by a Censor:

• Mr. Joël Séché, Chairman of the Board of Directors
• Mr. Guillaume Cadiou, Independent Director
• Mr. Philippe Guérin, Director representing the employees
• Mr. Maxime Séché, Director, Director General
• Ms Anne-Brigitte Spitzbarth, Independent Director
• Nathalie Tarnaud Laude, Independent Director
• Mr. Philippe Valletoux, Independent Director
• Mr. Guillaume Séché, Censor

The professional paths of the Directors appointed today are presented in the documents made available to shareholders at the Meeting and can be consulted on the Company's website.

The Board of Directors wishes to express its gratitude to Ms. Pascaline de Dreuzy and Ms. Nadine Koniski-Ziade and to Ms. Anne-Sophie Le Lay (who resigned on October 13, 2022). Their contributions have been valuable in defining Séché Environnement's strategy, including its internal structuring, external growth and social and environmental responsibility issues, in a period characterized by the strong development of the Group in France and internationally, and by the definition of a climate strategy aligned with the Paris Agreements.

The results of the votes by resolution and the minutes of the Assembly will be available as of May 3, 2023 on the Company's website: www.groupe-seche.com/en/investisseurs/meeting

Evolution of governance - Creation of a CSR Committee - Nominations

On 28 April 2023, the Board of Directors decided to refer from now on to the Middlenext Governance Code in place of the AFEP-MEDEF Code to which it was referring until then (see press release of April 28, 2023).

As a result of the adoption of the Middlenext Governance Code, the Board of Directors decided on the creation of a CSR Committee.

Following the appointment of the new Directors decided at today's General Meeting, the Board of Directors has appointed new members to the Audit Committee, the Strategic Committee and the Compensation and Nominating Committee.

The Committees are now composed as follows:

• Audit Committee:
• • Chairman: Mr. Guillaume Cadiou, Independent Director.
  • Members: Ms. Nathalie Tarnaud Laude, Independent Director, Mr. Philippe Valletoux, Independent Director.
• CSR Committee:
• • Chairman: Ms. Anne-Brigitte Spitzbarth, Independent Director.
  • Members: Ms. Nathalie Tarnaud Laude, Independent Director, Messrs. Philippe Guérin, Director representing employees and Philippe Valletoux, Independent Director.

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Consolidated results as of June 30, 2023

About Séché Environnement

Press release - April 28, 2023

• Strategy Committee:
• • Chairman: Mr. Maxime Séché, Director and Chief Executive Officer.
  • Member: Mr. Guillaume Cadiou, Independent Director.
• Compensation and Nominating Committee:
• • Chairman: Mr. Philippe Valletoux, Independent Director.
  • Members: Mr. Guillaume Cadiou, Independent Director, Ms. Nathalie Tarnaud Laude, Independent Director.

September 11, 2023 after market close

Séché Environnement is a leading player in waste management, including the most complex and hazardous waste, and in environmental services, particularly in the event of an environmental emergency.

Thanks to its expertise in the creation of circular economy loops, decarbonization, and hazard containment, the Group has been contributing to the ecological transition of industries and territories, as well as to the protection of the living world, for nearly 40 years. A French family-owned industrial group, Séché Environnement deploys the cutting-edge technologies developed by its R&D department at the heart of territories in more than 120 locations in 15 countries, including some 50 industrial sites in France. With over 5,700 employees, including 2,500 in France, Séché Environnement generated revenue of nearly €900 million in 2022, 30% of which from its international operations.

Séché Environnement has been listed on the Euronext Eurolist (Compartment B) since November 27, 1997. It is included in the CAC Mid&Small, EnterNext Tech 40 and EnterNext PEA-PME 150 indexes. ISIN: FR 0000039139 - Bloomberg: SCHP.FP - Reuters: CCHE.PA

CONTACTS

SÉCHÉ ENVIRONNEMENT

Analyst / Investor Relations	Media Relations
Manuel ANDERSEN	Anna JAEGY
Head of Investor Relations	Head of Communications
[e-mail]	[e-mail]
[phone]	[phone]

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