Solvay SA

Major Shareholding Notification • Dec 4, 2025

Transparency notification Form TR-1 BE PART I

1) Status of the notification
-------------------------------

Final

2) Issuer

Name SOLVAY Identification number 0403-091-220

3) Reason for the notification

Acquisition or disposal of financial instruments that are treated as voting securities

³ +

4) Notification by

A parent undertaking or a controlling person

² +

^A +

5) Persons subject to the notification requirement

Name	Address (for legal entities)
UBS Group AG	Bahnhofstrasse 45, 8001 Zürich	+

6) Persons that dispose of voting rights (only to be filled in if art. 7 of the Law applies)

Name	Address (for legal entities)

Please continue entering the information in part II concerning the persons referred to in Sections 5 and 6

Part II

7) Date on which the threshold is crossed

27.11.2025 (DD/MM/YYYY)

8) Threshold that is crossed (in %)

3

If the holding has fallen below the lowest threshold, you have the option of not entering any numbers in Section 10

9) Denominator

105,876,416

Please enter the denominator before filling in the data

10) Notified details

A) Voting rights	Previous notification		After the transaction
	# of voting rights		# of voting rights	% of voting rights
Holders of voting rights		Linked to securities	Not linked to the securities	Linked to securities	Not linked to the securities
UBS Group AG		0		0.00%
UBS AG		61,558		0.06%
UBS Europe SE		2,352		0.00%
UBS Asset Management (Singapore) Ltd		732		0.00%
UBS Asset Management (Europe) S.A.		34,968		0.03%
UBS Fund Management (Switzerland) AG		80,334		0.08%

Subtotal 179,944 0.17% ^S + TOTAL 179,944 0 0.17% 0.00%

Start with "groups" of holders. Add subtotals with Σ, and then finish with the persons who are "alone". For groups, start with the ultimate controlling natural person or legal entity. The totals, subtotals and % will be updated once you have clicked on .

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
UBS AG	Long Call Option	19.06.2026		135,000	0.13%	physical	-
UBS AG	Short Put Option	19.06.2026		395,000	0.37%	physical	-
UBS AG	Equity Swaps	28.03.2028		900	0.00%	cash	-
UBS AG	Right to Recall of Lent shares		At any time	431,774	0.41%	physical	-
UBS AG	Right to Substitute shares delivered as collaterals		At any time	7,680	0.01%	physical	-
UBS Switzerland AG	Right to Recall of Lent shares		At any time	21,113	0.02%	physical	-
UBS Switzerland AG	Right to Substitute shares delivered as collaterals		At any time	14,779	0.01%	physical	-
UBS Switzerland AG	Right of use over shares		At any time	3,334	0.00%	physical	-
UBS AG	Right of use over shares		At any time	17,934	0.02%	physical	-
UBS AG	Short Put Option	18.12.2026		285,000	0.27%	physical	-
UBS Switzerland AG	Right of use over Reverse Convertible		At any time	9,195	0.01%	cash	-
UBS AG	Swaps on Baskets	30.06.2026		80	0.00%	cash	-
UBS AG	Swaps on Baskets	01.06.2027		1,730,950	1.63%	cash	+
	TOTAL			3,052,739	2.88%

The totals will be updated once you have clicked on

OTAL (A & B)		# of voting rights	% of voting rights
	CALCULATE	3,232,683	3.05%

1	1)	Full chain of	controlled	undertakings	through	which the	holding is	effectively	held,	if applicable

Please see full chain of control attached.

12) In case of proxy voting f	or only one GM
			1	(DD/MM/YYYY)
Holder		will cease to hold / will hold again	voting rights as of

13) Additional information

he disclosure obligation arose due to the total indirect holdings of UBS Group AG in voting rights of Solvay SA, held directly by controlled undertakings, going above 3% on 27th November 2025.
	_

Done at	Zurich, Switzerland
---------	---------------------

On 02.12.2025 (DD/MM/YYYY)

Name & capacity Ewa Zajac

Associate Director Signature Iwona Konwinska Associate Director Signature

11. Information in relation to the person subject to the notification obligation – organizational
chart
UBS Group AG
UBS AG
UBS Asset Management AG
UBS Asset Management (Europe) S.A.
-
UBS Group AG
UBS AG
UBS Asset Management AG
UBS Asset Management (Singapore) Ltd
-
UBS Group AG
UBS AG
UBS Europe SE
-
UBS Group AG
UBS AG
UBS Asset Management AG
UBS Asset Management Switzerland AG
UBS Fund Management (Switzerland) AG
-
UBS Group AG
UBS AG
UBS Switzerland AG