Participation notification by Capital Group Companies Inc.

Brussels, Belgium – October 14, 2025 - 8:30 CEST

According to Belgian transparency legislation (Law of May 2, 2007), The Capital Group Companies, Inc. (333 South Hope Street 55fl. Los Angeles, CA 90071) recently sent Syensqo the following transparency notifications indicating that it crossed the threshold of 3%. Here is the summary of the moves:

Date on which the	Voting rights after the	Equivalent financial instruments	Total
threshold was crossed	transaction	after the transaction
October 06 2025	3.02%	0.00%	3.02%

The latest notification, dated October 08, 2025 and received on October 10, 2025, contains the following information:

Reason for the notification:
Acquisition or disposal of voting securities or voting rights
Notified by: The Capital Group Companies, Inc : A parent undertaking or a controlling person
Date on which the threshold is crossed: October 06, 2025
Threshold of direct voting rights crossed: 3% upwards
Denominator: 103,921,273
Additional information: The disclosure obligation arose due to voting rights attached to shares for The Capital Group Companies, Inc. going above 3%.
Persons subject to the notification requirement:

Name	Address (for legal entities)
The Capital Group Companies, Inc.	333 South Hope Street 55fl. Los Angeles, CA 90071

Notified details

A) Voting rights	Previous notification	After the transaction
	# of voting rights	# of voti	ing rights	% of voting rights
Holders of voting rights		Linked to securities	Not linked to the securities	Linked to securities	Not linked to the securities
The Capital Group Companies, Inc.		0	0	0,00%	0,00%
Capital Research and Management Company		3 137 243	0	3,02%	0,00%
Subtotal		3 137 243		3,02%	0,00%
TOTAL		3 137 243	0	3,02%	0,00%

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B) Equivalent financial instruments	After the transaction
Holders of equivalent financial instruments	Type of financial instrument	Expiration date	Exercise period or date	# of voting rights that may be acquired if the instrument is exercised	% of voting rights	Settlement

TOTAL			0	0,00%
The totals will be updated once you have clicked on
TOTAL (A & B)			# of voting rights	% of voting rights
			CALCULATE	3 137 243	3,02%

Transparency notifications and the full chain of controlled undertakings through which the holding is effectively held is available on the Investor Relations Section of Syensqo's website.

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Contacts

Investors & Analysts Media

[email protected] [email protected]

Sherief Bakr +44 7920 575 989 Perrine Marchal +32 478 32 62 72

Robbin Moore-Randolph +1 470 493 2433

Loïc Flament +32 478 69 74 20 Laetitia Schreiber +32 487 74 38 07

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Syensqo is a science company developing groundbreaking solutions that enhance the way we live, work, travel and play. Inspired by the scientific councils which Ernest Solvay initiated in 1911, we bring great minds together to push the limits of science and innovation for the benefit of our customers, with a diverse, global team of more than 13,000 associates.

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