National Storage Mechanism | Additional information

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FORM 8.3

IRISH TAKEOVER PANEL

OPENING POSITION DISCLOSURE/DEALING DISCLOSURE UNDER RULE 8.3 OF THE IRISH TAKEOVER PANEL ACT, 1997, TAKEOVER

RULES, 2022 BY PERSONS WITH INTERESTS IN RELEVANT SECURITIES REPRESENTING 1% OR MORE

1. KEY INFORMATION

(a) Full name of discloser	Citadel Group
(b) Owner or controller of interests and short positions disclosed, if different from 1(a) The naming of nominee or vehicle companies is insufficient. For a trust, the trustee(s), settlor and beneficiaries must be named.	N/A
(c) Name of offeror/offeree in relation to whose relevant securities this form relates Use a separate form for each offeror/offeree	HORIZON THERAPEUTICS PLC
(d) If an exempt fund manager connected with an offeror/offeree, state this and specify identity of offeror/offeree (Note 1)	N/A
(e) Date position held/dealing undertaken For an opening position disclosure, state the latest practicable date prior to the disclosure	5 April 2023
(f) In addition to the company in 1(c) above, is the discloser also making disclosures in respect of any other party to the offer? If it is a cash offer or possible cash offer, state "N/A"	N/A

2. INTERESTS AND SHORT POSITIONS

If there are interests and short positions to disclose in more than one class of relevant securities of the offeror or offeree named in 1(c), copy table 2 for each additional class of relevant security.

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Interests and short positions in the relevant securities of the offeror or offeree to which the disclosure relates following the dealing (if any)

(Note 2)

Class of relevant security (Note 3)	Common Stock ISIN IE00BQPVQZ61
	Interests		Short positions
	Number	%	Number	%
(1) Relevant securities owned and/or controlled	3,981,563	1.74	0	0.00
(2) Cash-settled derivatives	0	0.00	0	0.00
(3) Stock-settled derivatives (including options) and agreements to purchase/ sell	0	0.00	0	0.00
Total	3,981,563	1.74	0	0.00

All interests and all short positions should be disclosed.

Details of options including rights to subscribe for new securities and any open stock-settled derivative positions (including traded options), or agreements to purchase or sell relevant securities, should be given on a Supplemental Form 8.

3. DEALINGS (IF ANY) BY THE PERSON MAKING THE DISCLOSURE (Note 4)

Where there have been dealings in more than one class of relevant securities of the offeror or offeree named in 1(c), copy table 3(a), (b), (c) or (d) (as appropriate) for each additional class of relevant security dealt in.

The currency of all prices and other monetary amounts should be stated.

(a) Purchases and sales

Class of relevant security	Purchase/sale	Number of securities	Price per unit (Note 5)
Common	Buy Transaction	325	107.8169 USD
Common	Buy Transaction	100	107.9350 USD
Common	Buy Transaction	1,000	107.9500 USD
Common	Buy Transaction	300	108.2033 USD
Common	Buy Transaction	694	108.4212 USD
Common	Buy Transaction	697	108.5091 USD
Common	DVP Transaction	1,918	107.9900 USD
Common	RVP Transaction	1,918	107.9900 USD
Common	Sell Transaction	1,918	107.9900 USD
Common	Sell Transaction	109	108.0997 USD
Common	Sell Transaction	117	108.3760 USD
Common	Sell Transaction	883	108.4240 USD
Common	Sell Transaction	231	108.5497 USD
Common	Sell Transaction	210	108.6019 USD

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(b) Cash-settled derivative transactions

Class of
relevant
security

Product
description
e.g. CFD

Nature of dealing
e.g. opening/ closing a long/ short position, increasing/ reducing a long/ short position

Number of
reference
securities
(Note 6)

Price
per unit
(Note 5)

(i) Writing, selling, purchasing or varying

Class of
relevant
security

Product
description e.g. call
option

Writing, purchasing, selling, varying
etc.

Number
of
securities
to which
option
relates
(Note 6)

Exercise
price per
unit

Type
e.g.
American,
European
etc.

Expiry
date

Option
money
paid/
received per unit

(ii) Exercise

Class of
relevant
security

Product
description
e.g. call
option

Exercising/
exercised
against

Number of
securities

Exercise
price per
unit
(Note 5)

(d) Other dealings (including transactions in respect of new securities) (Note 3)

Class of relevant security	Nature of dealing e.g. subscription, conversion, exercise	Details	Price per unit (if applicable) (Note 5)

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4. OTHER INFORMATION

(a) Indemnity and other dealing arrangements

Details of any indemnity or option arrangement, or any agreement or understanding, formal or informal, relating to relevant securities which may be an inducement to deal or refrain from dealing entered into by the person making the disclosure and any party to the offer or any person acting in concert with a party to the offer.

Irrevocable commitments and letters of intent should not be included. If there are no such agreements, arrangements or understandings, state "none"

None

(b) Agreements, arrangements or understandings relating to options or derivatives

Full details of any agreement, arrangement or understanding between the person disclosing and any other person relating to the voting rights of any relevant securities under any option referred to on this form or relating to the voting rights or future acquisition or disposal of any relevant securities to which any derivative referred to on this form is referenced. If none, this should be stated.

None

Is a Supplemental Form 8 attached?

Date of disclosure	6 April 2023
Contact name	Paula Sharp
Telephone number	020 7645 9700

Public disclosures under Rule 8.3 of the Rules must be made to a Regulatory Information Service.