Indivior : Notice of 2024 General Meeting

THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION. If you are in any doubt about the action to be taken, you should immediately consult your stockbroker, solicitor, accountant or other independent advisor who, if you are taking advice in the United Kingdom, is duly authorized under the Financial Services and Markets Act 2000, or an appropriately authorized independent advisor if you are in a territory outside the United Kingdom.

If you have recently sold or transferred all of your shares in Indivior PLC, please forward this document, together with the accompanying documents (but not the personalized Form of Proxy), as soon as possible either to the purchaser or transferee or to the person who arranged the sale or transfer so they can pass these documents to the person who now holds the shares. If you have sold or otherwise transferred only part of your holding, you should retain this document and its enclosures.

Indivior PLC

(incorporated in the United Kingdom with registered number 09237894)

Proposed transfer of Indivior's listing category on the

Official List from Premium to Standard to effect a primary listing in the U.S.

and

Notice of General Meeting

You should read the whole of this document. Your attention is drawn to the letter from the Chair of Indivior which is set out in Part I (Letter from the Chair of Indivior PLC) and which contains the unanimous recommendation of the directors of Indivior that you vote in favor of the resolution to be proposed at the General Meeting referred to below (the "Resolution").

Subject to the Resolution being passed, an application will be made to the FCA for the category of Indivior's listing of Indivior Shares on the Official List to be transferred from a Premium Listing to a Standard Listing (the "Proposed Transfer"). Following the Proposed Transfer, Indivior Shares will remain eligible for trading on the Main Market of the London Stock Exchange for listed securities (as a Standard Listing segment issuer) and the listing of Indivior Shares on the Nasdaq Stock Market will continue unchanged.

The Notice of General Meeting to be held at the offices of Freshfields Bruckhaus Deringer, 100 Bishopsgate, London, EC2P 2SR, United Kingdom at 12.00p.m. (U.K. time) on Thursday, May 23, 2024 is set out on page 14 of this document. A Form of Proxy for use in connection with the General Meeting is enclosed and, to be valid, should be completed, signed and returned following the procedures described in the notes to the Notice of General Meeting so as to be received by the Registrar, Computershare Trust Company, N.A., at P.O. Box 43118, Providence, RI 02940-5132, U.S. as soon as possible but, in any event, so as to arrive no later than 12.00p.m. (U.K. time) on Tuesday, May 21, 2024. Alternatively to completing the hard-copy Form of Proxy, you may submit your proxy vote electronically via the InvestorVote service at www.investorvote.com/INPLGM, where full details of the procedure are given. Indivior Shareholders are advised to read the terms and conditions of use carefully and will need the Control Number set out on the Form of Proxy. Electronic proxy appointments must be received by the Company's Registrar, Computershare Trust Company, N.A., by no later than 12.00p.m. (U.K. time) on Tuesday, May 21, 2024.

If you hold Indivior PLC U.K. Depositary Interests directly, you are entitled to provide voting instructions to Computershare Investor Services PLC ("Computershare U.K."), in its capacity as DI Depositary, in respect of the U.K. Depositary Interests registered in your name in accordance with the procedures described in the notes to the Notice of General Meeting and by following the instructions on the Form of Instruction that will accompany this document. Voting instructions must be received by no later than 12.00p.m. (U.K. time) on Monday, May 20, 2024.

If you hold Indivior PLC U.K. Depositary Interests via the CSN, you are entitled to provide voting instructions to Computershare U.K., in its capacity as DI Depositary, in respect of the U.K. Depositary Interests that you are beneficially entitled to in accordance with the procedures described in the notes to the Notice of General Meeting and by following the instructions on the Form of Direction that will accompany this document. Voting instructions must be received by no later than 12.00p.m. (U.K. time) on Friday, May 17, 2024.

If your shares are held in a stock brokerage account or by a broker, bank or other nominee, you are considered the beneficial owner of Indivior Shares, and this Notice of General Meeting is being made available or forwarded to you by or on behalf of your broker, bank or other nominee. As the beneficial owner, you may have the right to direct your broker, bank or other nominee on how to vote your shares by following the instructions for voting on the voting instruction form that will accompany this document. Your broker, bank or nominee will have their own cut-off time for receipt of voting instructions. If you do not direct your broker, bank or other nominee on how to vote your shares by following the instructions on the voting instruction form, your Indivior Shares will not be voted at the General Meeting.

A summary of the action to be taken by Indivior Shareholders is set out in section 5 of Part I (Letter from the Chair of Indivior PLC) and in the Notice of General Meeting.

Capitalized terms have the meanings ascribed to them in Part III (Definitions) of this document.

This document is published on May 3, 2024.

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CONTENTS
SECTION	PAGE
EXPECTED TIMETABLE OF PRINCIPAL EVENTS	4
IMPORTANT CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	5
PART I LETTER FROM THE CHAIR OF INDIVIOR PLC	6
PART II A SUMMARY OF THE DIFFERENCES BETWEEN STANDARD AND PREMIUM
CATEGORIES OF LISTING	10
PART III DEFINITIONS	11
NOTICE OF GENERAL MEETING	14
GENERAL INFORMATION	15
NOTES FOR DIRECT HOLDERS OF INDIVIOR SHARES	16
NOTES FOR HOLDERS OF INDIVIOR PLC U.K. DEPOSITARY INTERESTS (OTHER THAN
VIA THE INDIVIOR PLC CORPORATE SPONSORED NOMINEE FACILITY)	19
NOTES FOR HOLDERS OF INDIVIOR PLC U.K. DEPOSITARY INTERESTS VIA THE
INDIVIOR PLC CORPORATE SPONSORED NOMINEE FACILITY ("CSN")	21
NOTES FOR OTHER BENEFICIAL OWNERS	22
CONTACT DETAILS	23

Indivior ⅼ Notice of General Meeting 2024

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EXPECTED TIMETABLE OF PRINCIPAL EVENTS

The dates given are based on Indivior's current expectations and may be subject to change. If any of the times or dates below change, Indivior will give notice of the change by issuing an announcement through a Regulatory Information Service.

All times shown in this timetable are U.K. time unless otherwise stated.

Event	Expected time/date
Record date for DTC beneficial owners to be eligible to vote	Friday, May 10, 2024
Latest time and date for receipt of Forms of Direction	12.00p.m. on
(U.K. CSN holders)	Friday, May 17, 2024
Record date for CSN holders to be eligible to vote	6.00p.m. on
	Friday, May 17, 2024
Record date for U.K. Depositary Interest holders to be eligible to vote	6.00p.m. on
	Friday, May 17, 2024
Latest time and date for receipt of Forms of Instruction	12.00p.m. on
(U.K. Depositary Interest holders)	Monday, May 20, 2024
Latest time and date for receipt of Forms of Proxy	12.00p.m. on
(direct shareholders)	Tuesday, May 21, 2024
Record date for direct shareholders to attend and vote	12.00p.m. on
at the General Meeting	Tuesday, May 21, 2024
General Meeting	12.00p.m. on
	Thursday, May 23, 2024
Proposed Transfer becomes effective and trading of Indivior Shares	8.00a.m. on
commences as a Standard Listing company	Thursday, June 27, 2024

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IMPORTANT CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This document contains certain statements that are forward-looking.Forward-looking statements include, among other things, statements regarding the expected completion, and timing of completion, of the Proposed Transfer; our expectations regarding potential inclusion in U.S. indices over time; our intention to report on U.S. forms beginning January 1, 2025; our intention to maintain Indivior's U.K. listing as a secondary listing following the transition of our primary listing to the U.S. for as long as it is considered to be in the best interests of Indivior and its shareholders as a whole; and other statements containing the words "believe", "anticipate", "plan", "expect", "intend", "estimate", "forecast", "strategy", "target", "guidance", "outlook", "potential", "project", "priority", "may", "will", "should", "would", "could", "can", "outlook", "guidance", the negatives thereof, and variations thereon and similar expressions. By their nature, such forward-looking statements involve risks and uncertainties as they relate to events or circumstances that may or may not occur in the future. Actual results may differ materially from those expressed or implied in these forward-looking statements.

The forward-looking statements in this document are made based upon our current expectations and beliefs concerning future events and involve a number of known and unknown risks and uncertainties. Such forward-looking statements are based on numerous assumptions regarding our present and future business strategy and the environment in which we operate, which may prove to be inaccurate. In particular, the achievement of such statements could be affected by, among other things: an unsuccessful shareholder vote; the actions of the FCA; changed circumstances; the discretion exercised by any U.S. index; and the material risks described in the most recent Indivior PLC Annual Report and in subsequent releases.

Forward-looking statements contained in this document apply only at the date of this document. To the extent required by applicable law or regulation, including pursuant to the Listing Rules, the DTRs and the U.K. Market Abuse Regulation, Indivior will update or revise the information in this document, as appropriate. Otherwise, Indivior is under no obligation, and Indivior expressly disclaims any intention or obligation, to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

Indivior ⅼ Notice of General Meeting 2024

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PART I

LETTER FROM THE CHAIR OF INDIVIOR PLC

Indivior PLC

(incorporated in the United Kingdom with registered number 09237894)

Directors:	Registered office:
Graham Hetherington (Chair)	Indivior PLC
Mark Crossley (Chief Executive Officer)	234 Bath Road
Ryan Preblick (Chief Financial Officer)	Slough
Peter Bains (Independent Non-Executive Director)	Berkshire
Dr. Keith Humphreys (Independent Non-Executive Director)	United Kingdom
Jerome Lande (Non-Executive Director)	SL1 4EE
Joanna Le Couilliard (Independent Non-Executive Director)
Barbara Ryan (Independent Non-Executive Director)
Mark Stejbach (Independent Non-Executive Director)
Juliet Thompson (Senior Independent Director)
May 3, 2024
Dear Indivior Shareholder,

Proposed transfer of Indivior's listing category on the Official List from a Premium Listing to a Standard Listing to effect a primary listing in the U.S.

1. Introduction and background

On July 28, 2022, the Indivior Board announced its intention to seek the formal approval of Indivior Shareholders for the additional listing of Indivior Shares on a U.S. stock exchange (the "Additional U.S. Listing"). In the shareholder circular relating to the Additional U.S. Listing published on September 5, 2022, the Indivior Board announced that the Additional U.S. Listing would also provide the Company with the optionality to pursue, as a second step, a primary U.S. listing. The Additional U.S. Listing was approved by Indivior Shareholders at a general meeting of the Company on September 30, 2022, with 99.95% of votes cast in favor. The Additional U.S. Listing became effective on June 12, 2023, and Indivior Shares are currently listed both on the Official List (Premium Listing) in London and on the Nasdaq Stock Market in New York.

Subsequently, on February 22, 2024, the Indivior Board announced its intention to consult with shareholders about the proposed relocation of Indivior's primary listing from the U.K. to the U.S. by way of the proposed transfer of Indivior's listing category on the Official List from a Premium Listing (commercial company) to a Standard Listing (shares) (the "Proposed Transfer").

Having completed its consultation with shareholders the Indivior Board announced on April 25, 2024 that, following careful consideration of the feedback received, it had decided to seek the approval of Indivior Shareholders for the Proposed Transfer. At the same time, the Indivior Board announced that it intends to maintain Indivior's U.K. listing as a secondary listing following the transition of its primary listing to the U.S. for as long as it is considered to be in the best interests of Indivior and Indivior Shareholders as a whole.

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2. Reasons for U.S. primary listing

As set out in the announcement dated February 22, 2024, the Board believes a primary U.S. listing will be beneficial to Indivior as it would:

• reflect the Group's current and future growth opportunities for its proprietary treatments (SUBLOCADE, PERSERIS and OPVEE), which are centered in the U.S.;
• be expected to attract more U.S. investors and analysts by further elevating the Group's leadership profile in addiction treatment in U.S. capital markets;
• allow for inclusion in major U.S. indices over time; and
• reflect the growing proportion of the Group's share capital owned by U.S.-based investors, which is currently approaching 50%.

Following the Proposed Transfer, Indivior intends to transition to reporting in U.S. GAAP on the forms applicable to a U.S. domestic issuer for its annual report and quarterly reports commencing January 1, 2025 (regardless of whether or not Indivior has lost its status as a foreign private issuer for U.S. securities laws purposes by then). Accordingly, Indivior intends to release its first annual report on Form 10-K in March 2025 in respect of the financial year ending December 31, 2024, and its first quarterly report on Form 10-Q in May 2025 in respect of the first financial quarter ending March 31, 2025. Reporting on U.S. domestic forms and maintaining a primary U.S. listing are both eligibility requirements for inclusion in important U.S. stock indices, which is a major driver of domestic U.S. fund ownership. The orderly transition to indexation on U.S. indices is an important objective of the Company as the Proposed Transfer is expected to result in Indivior ceasing to be eligible for inclusion in certain U.K. stock indices, including the FTSE 250.

While Indivior expects to become eligible for inclusion in U.S. stock indices in due course following the Proposed Transfer, it is acknowledged that inclusion in these important indices is unlikely to be achieved in the very near term, as it may take some time to demonstrate that the Company has met all the relevant eligibility criteria (including the speed at which the overall balance of trading volume and liquidity migrates to the Nasdaq Stock Market). It is also the case that the providers of certain U.S. indices retain a higher level of discretion around the applicability of eligibility criteria and the time at which companies may be admitted to the relevant index. The Indivior Board nonetheless believes that the overall strategic and capital markets advantages of a primary U.S. listing outweigh these short- term considerations.

3. Transfer to a Standard Listing

Under the Listing Rules, the Proposed Transfer requires Indivior to first obtain the prior approval of Indivior Shareholders. Indivior Shareholders will be asked to vote on the Resolution relating to the Proposed Transfer at the General Meeting on Thursday, May 23, 2024. The approval by special resolution of a majority of not less than 75% of the votes attaching to the Indivior Shares voted on the Resolution (whether in person or by proxy) at the General Meeting will be required.

If the Proposed Transfer does not occur because Indivior Shareholders do not vote in favor of the Resolution, then Indivior's Premium Listing will continue and its primary listing location will remain in the U.K.

Pursuant to the Listing Rules, the date of the Proposed Transfer must not be less than 20 U.K. business days after the passing of the Resolution. The Indivior Board proposes to apply promptly for the Proposed Transfer to be effected and so, subject to the passing of the Resolution, it is anticipated that the date of the Proposed Transfer will be Thursday, June 27, 2024. Indivior Shares will, on completion of the Proposed Transfer, continue to be traded on the Main Market, but under the designation "Listed: Standard".

As a company with a Standard Listing, Indivior will remain subject to the Listing Rules (as applicable to a company whose equity shares have a Standard Listing), the Prospectus Rules and the DTRs. However it will not be required to comply with the super-equivalent provisions of the Listing Rules which apply to companies with a Premium Listing (including provisions which provide shareholders of companies with a Premium Listing with rights to vote on significant and related party transactions).

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Following the Proposed Transfer, the Indivior Board intends to maintain the Standard Listing for as long as it is considered to be in the best interests of Indivior and Indivior Shareholders as a whole.

In December 2023, the FCA published its consultation paper CP23/31 ('Primary Markets Effectiveness Review: Feedback to CP23/10 and detailed proposals for listing rules reforms') setting out a series of proposed reforms to the Listing Rules, including the proposed removal of the current "Premium" and "Standard" listing segments and the introduction of new listing categories in their place (the "Proposed Listing Rules Reforms"). As at the date of publication of this document, the scope and application of the proposed new listing categories is not yet final and, in particular, it is not yet clear which new listing category Indivior will be mapped to following implementation of the Proposed Transfer. However, taking into account the proposed approach to existing Standard listed issuers under the Proposed Listing Rules Reforms, Indivior currently expects that the overall burden of compliance for it under the New Listing Rules will be substantially equivalent to that of the current Standard Listing category. The final New Listing Rules are currently expected to be implemented early in the second half of 2024 and the Indivior Board will update Indivior Shareholders by way of announcement through a Regulatory Information Service once it is clear which new listing category Indivior will be mapped to under the new rules.

The Indivior Board has not made, and does not anticipate or intend to make, any changes to the operation of Indivior's business in connection with the Proposed Transfer.

Furthermore, the Proposed Transfer will not affect the way in which Indivior Shareholders have held, bought or sold Indivior Shares since the implementation of the Additional U.S. Listing.

A more detailed summary of the differences between the regulatory requirements of companies with a Standard Listing and those with a Premium Listing is contained at Part II (A summary of the difference between Standard and Premium categories of listing) of this document.

4. Corporate governance following the Proposed Transfer

As a company with a Standard Listing (and, following implementation of the Proposed Listing Rules Reforms, a company that Indivior expects will be subject to continuing obligations that are substantially equivalent to those that currently apply to a company with a Standard Listing), Indivior will no longer be required to comply (or explain non-compliance) with the U.K. Corporate Governance Code, although it will still be required to make a corporate governance statement under paragraph

7.2 of the DTRs and will be subject to those requirements of the FCA which are applicable to its new category of listing. Against this background, Indivior expects to adjust its corporate governance arrangements over time so as to align with those typically adopted by U.S. domestic issuers of a similar size and nature. As a U.K. company, Indivior will remain subject to the Takeover Code and English company law.

In addition, the governance rules and regulations of the Nasdaq Stock Market and U.S. securities laws have applied to Indivior since the effectiveness of the Additional U.S. Listing in June 2023, although as a foreign private issuer for U.S. securities laws purposes, Indivior is permitted to follow certain home country corporate governance practices. These rules and regulations include, inter alia, requirements with respect to director independence, standards for audit, nomination and remuneration board committees, board approval of related person transactions and shareholder approval of certain share issuances. As set out above, following the Proposed Transfer, Indivior intends to transition to reporting in U.S. GAAP commencing January 1, 2025.

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5. Action to be taken

As outlined above, the Proposed Transfer is conditional on the approval of Indivior Shareholders. This will be sought at the General Meeting to be held at 12.00p.m. (U.K. time) on Thursday, May 23, 2024 at the offices of Freshfields Bruckhaus Deringer, 100 Bishopsgate, London EC2P 2SR, United Kingdom. A notice convening the General Meeting at which the Resolution will be proposed is set out on page 14 of this document.

Please note that attendance and voting procedures differ depending on how you hold your Indivior Shares. Specific instructions are set out in the notes to the Notice of General Meeting on the following pages:

• Direct shareholdings, see page 16
• U.K. Depositary Interests in CREST (other than via the Indivior PLC Corporate Sponsored Nominee Facility), see page 19
• U.K. Depositary Interests in CREST via the Indivior PLC Corporate Sponsored Nominee Facility, see page 21
• Other beneficial owners, see page 22

6. Recommendation

In the Indivior Board's opinion, the Proposed Transfer is in the best interests of the Company and its shareholders as a whole and is most likely to promote the success of the Company for the benefit of its shareholders as a whole. Accordingly, the Indivior Board unanimously recommends that all Indivior Shareholders vote in favor of the Resolution at the General Meeting, as the Directors intend to do in respect of their own beneficial holdings of Indivior Shares.

Yours faithfully,

Graham Hetherington

Chair

Indivior PLC

Indivior ⅼ Notice of General Meeting 2024

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PART II

A SUMMARY OF THE DIFFERENCES BETWEEN STANDARD AND PREMIUM CATEGORIES OF LISTING

The following paragraphs set out the key differences between Standard and Premium categories of Listing.

1. Companies with a Standard Listing are not eligible for inclusion in the U.K. series of FTSE indices.
2. Companies with a Standard Listing are not required to retain a sponsor for certain transactions.
3. Companies with a Standard Listing are not required to comply with the additional six Premium Listing Principles contained in Listing Rule 7.2.1A, which only apply to companies with a Premium Listing.
4. Companies with a Standard Listing are not required to: (i) control the majority of their assets and to have done so for the last three years; and (ii) carry on an independent business as their main activity.
5. A Standard Listing does not require a company to offer pre-emption rights pursuant to the Listing Rules. However, Indivior Shareholders will continue to benefit from pre-emption rights following the Proposed Transfer as a result of the continued application of English company law.
6. A Standard Listing does not require a company to comply with the provisions of Listing Rule 10 which sets out requirements for shareholders to be notified of certain transactions and to have the opportunity to vote on proposed significant transactions.
7. A Standard Listing does not require a company to comply with Listing Rule 11 which contains rules intended to prevent a related party from taking advantage of its position in respect of transactions with the listed company.
8. Companies with a Standard Listing are not required to comply with Listing Rule 12 which applies to companies dealing in their own securities; however, any dealings in such companies' securities will continue to be subject to other general restrictions including those contained in the U.K. Market Abuse Regulation.
9. The U.K. Corporate Governance Code does not apply to companies with a Standard Listing. However, pursuant to paragraph 7.2 of the DTRs, companies with a Standard Listing are still required to make a corporate governance statement in the directors' report which references the corporate governance code to which the company is subject, a description of the main features of the company's internal control and risk management systems in relation to the financial reporting process, information about its share capital and a description of the composition and operation of its committees.
10. A company with a Standard Listing is not required to comply with the more extensive requirements relating to the content of circulars issued to shareholders of companies with a Premium Listing as detailed in Chapter 13 of the Listing Rules.
11. A company with a Standard Listing is not required to comply with a number of miscellaneous continuing obligations imposed by Chapter 9 of the Listing Rules on companies with a Premium Listing.
12. Companies with a Standard Listing are not required to obtain the approval of shareholders for the cancellation of the listing.

Taking into account the proposed approach to existing Standard listed issuers under the Proposed Listing Rules Reforms, Indivior currently expects that the overall burden of compliance for it under the New Listing Rules will be substantially equivalent to that of the current Standard Listing category.

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