Smurfit Kappa : Circular re Scheme Meeting and EGM

THIS CIRCULAR AND THE ACCOMPANYING FORMS OF PROXY FOR THE SHAREHOLDER MEETINGS ARE IMPORTANT AND REQUIRE YOUR IMMEDIATE ATTENTION. If you are in any doubt about the contents of this Circular or the action you should take, you are recommended to seek your own personal financial advice as soon as possible from your stockbroker, bank, solicitor, accountant or other appropriate independent professional financial adviser (being, in the case of Smurfit Kappa Shareholders in Ireland, an organisation or firm authorised or exempted under the Investment Intermediaries Act, 1995 of Ireland (as amended) or the European Union (Markets in Financial Instruments) Regulations 2017 (as amended) or, in the case of Smurfit Kappa Shareholders in the United Kingdom, an adviser authorised pursuant to the Financial Services and Markets Act 2000, or from another appropriately authorised independent financial adviser if you are in a territory outside Ireland or the United Kingdom).

Capitalised terms used in this Circular are defined in Part XI (Definitions) of this Circular.

Except where stated otherwise or where the context otherwise requires, where the term "Smurfit Kappa Shareholder" is used in this Circular, it refers to a holder of equity securities of Smurfit Kappa regardless of whether the equity securities are traded on the LSE's main market for listed securities in the form of Smurfit Kappa CDIs or quoted on Euronext Dublin in the form of Smurfit Kappa Shares. Similarly, where the term "Smurfit Kappa Share" is used in this Circular in relation to Smurfit Kappa, it includes Smurfit Kappa CDIs, where appropriate. Further, in this Circular, references to "Smurfit WestRock Shares" in the context of the admission to trading on the LSE's main market for listed securities include any Smurfit WestRock DIs.

If you sell or have sold or otherwise transferred your entire holding of Smurfit Kappa Shares, please send this Circular, together with the accompanying Forms of Proxy for the Shareholder Meetings, as soon as possible to the purchaser or transferee, or to the stockbroker, bank or other agent through whom the sale or transfer was effected for onward transmission to the purchaser or transferee. However, such documents should not be forwarded or transmitted in or into any jurisdiction in which such act would constitute a violation of the relevant laws or regulations in such jurisdiction. If you sell or have sold or otherwise transferred only part of your holding of Smurfit Kappa Shares, you should retain this Circular and the accompanying Forms of Proxy and immediately consult the stockbroker, bank or other agent through whom the sale or transfer was effected.

A Prospectus relating to the admission of the Smurfit WestRock Shares to the standard listing segment of the Official List of the FCA and to trading on the LSE's main market for listed securities, and a US Registration Statement pursuant to which the offer and sale of Smurfit WestRock Shares to WestRock Shareholders pursuant to the Merger have been registered pursuant to the US Securities Act, have, in addition to this Circular, been published on Smurfit Kappa's website, at www.smurfitkappa.com/investors/ meetings2024. This Circular should be read in conjunction with the Prospectus and US Registration Statement. This Circular, the Prospectus and the US Registration Statement will also be available on request from Smurfit Kappa. To request copies, please contact Smurfit Kappa by phone on [phone]. Lines are open 9:00 a.m. to 5:00 p.m., Monday to Friday (excluding public holidays in Ireland and England).

This Circular is not a prospectus, and it does not constitute or form part of any offer or invitation to purchase, acquire, subscribe for, sell, dispose of or issue, or any solicitation of any offer to sell, dispose of, purchase, acquire or subscribe for, any security, including any Smurfit WestRock Shares to be issued to Smurfit Kappa Shareholders and WestRock Shareholders in connection with the Combination.

The distribution of this Circular and/or the accompanying documents (in whole or in part) in jurisdictions other than the United Kingdom or Ireland may be restricted by the laws of those jurisdictions and therefore persons into whose possession this Circular comes should inform themselves about and observe any such restrictions. Failure to comply with any such restrictions may constitute a violation of the securities laws of any such jurisdiction.

SMURFIT KAPPA GROUP PLC

(incorporated and registered in Ireland under the Irish Companies Act with

registered number 433527)

Proposed Combination of

Smurfit Kappa and WestRock

Proposed acquisition of Smurfit Kappa Group plc by Smurfit WestRock to be effected by means of a Scheme of Arrangement under Section 450 of the Companies Act 2014 of Ireland

and

Proposed merger of Sun Merger Sub, LLC (a wholly-owned subsidiary of Smurfit

WestRock) with and into WestRock Company

Circular to Smurfit Kappa Shareholders and Explanatory Statement under Section 452

of the Companies Act 2014 of Ireland

Notice of Scheme Meeting

and

Notice of Extraordinary General Meeting

This Circular should be read as a whole. Your attention, in particular, is drawn to the letter from the Chair, which is set out on pages 20 to 37 of this Circular and which contains the unanimous recommendation of the Smurfit Kappa Board that you vote in favour of the Resolutions to be proposed at the Shareholder Meetings referred to below. Your attention is also drawn in particular to the risk factors set out in Part II (Risk Factors) of this Circular.

Notice of an Irish High Court convened shareholder meeting (the "Scheme Meeting") to be held at 10:00 a.m. on 13 June 2024 in the Minerva Suite, RDS, Merrion Road, Ballsbridge, Dublin 4, D04 AK83, Ireland is set out at page 217 of this Circular.

Notice convening an Extraordinary General Meeting (the "EGM") to be held at 10:15 a.m. on 13 June 2024, or if later, as soon as possible following the conclusion or adjournment of the Scheme Meeting in the Minerva Suite, RDS, Merrion Road, Ballsbridge, Dublin 4, D04 AK83, Ireland is also set out at page 221 of this Circular.

A Form of Proxy for use at the Scheme Meeting and a Form of Proxy for use at the EGM are enclosed (the "Forms of Proxy", and each a "Form of Proxy"). To be valid, Forms of Proxy, completed in accordance with the instructions printed thereon, must be returned to the Company Registrar of Smurfit Kappa, Computershare Investor Services (Ireland) Limited, P.O. Box 13030, Dublin 24, Ireland (if delivered by post) or to Computershare Investor Services (Ireland) Limited, 3100 Lake Drive, Citywest Business Campus, Dublin 24, D24 AK82, Ireland (if delivered by hand) by (i) no later than 10:00 a.m. on 11 June 2024 in the case of the Scheme Meeting, and (ii) no later than 10:15 a.m. on 11 June 2024 in the case of the EGM (or, in the case of an adjournment, no later than 48 hours before the time fixed for holding the adjourned meeting).

Alternatively, Smurfit Kappa Shareholders may appoint a proxy electronically, by visiting the website of the Company Registrar of Smurfit Kappa at www.eproxyappointment.com; to do this, Smurfit Kappa Shareholders will need their shareholder reference number (SRN), control number and PIN, all of which can be found on their Form of Proxy.

Electronic proxy voting by Euroclear Nominees Limited in respect of the ordinary shares registered in the name of Euroclear Nominees Limited as nominee for Euroclear Bank may also occur through the use of a secured mechanism to exchange electronic messages as agreed by the Company with Euroclear Bank.

Persons who hold their interests in Smurfit Kappa Shares as Belgian Law Rights through the Euroclear system or as CDIs through the CREST System should consult with their stockbroker or other intermediary at the earliest opportunity for further information on the processes and timelines for submitting proxy votes for the AGM through the respective systems.

For voting services offered by custodians holding Irish corporate securities directly with Euroclear Bank, please contact your custodian. All proxy voting instructions (whether submitted directly or through the Euroclear or (via a holding of CDIs) CREST Systems) must be received by the Company's Registrar not less than 48 hours before the time appointed for the relevant meeting or any adjournment of that meeting. However, persons holding through the Euroclear or (via a holding of CDIs) CREST Systems will also need to comply with any additional voting deadlines imposed by the respective service offerings. Again, all persons affected are recommended to consult with their stockbroker or other intermediary at the earliest opportunity.

Citi, which is authorised by the PRA and regulated by the FCA and the PRA in the United Kingdom, is acting as financial adviser and sponsor to Smurfit Kappa and no one else in connection with the Combination. PJT Partners, which is authorised and regulated by the FCA in the United Kingdom, is acting as financial adviser to Smurfit Kappa and no one else in connection with the Combination and matters described in the Circular. In connection with such matters, Citi and PJT Partners, their affiliates and their respective directors, officers, employees and agents will not regard any other person (whether or not a recipient of this Circular) as their client, nor will they be responsible to anyone other than Smurfit Kappa for providing the protections afforded to their clients or for providing advice in relation to the Combination, the contents of this Circular or any transaction arrangement or other matter referred to herein. Apart from the responsibilities and liabilities, if any, which may be imposed on Citi and PJT Partners by FSMA or the regulatory regime established thereunder, or under the regulatory regime of any jurisdiction where exclusion of liability under the relevant regulatory regime would be illegal, void or unenforceable, Citi, PJT Partners and their respective affiliates, directors, officers, employees and advisers, accept no responsibility or liability whatsoever (directly or indirectly, whether in tort, statute or otherwise) for, and do not make any representation or warranty, express or implied, as to the contents of this Circular, including its accuracy, completeness or verification or for any other statement made or purported to be made in connection with Smurfit Kappa, WestRock, the Combined Group or the Combination, and nothing in this Circular is or shall be relied upon as a promise or representation in this respect, whether as to the past or future. Citi and PJT Partners accordingly disclaim to the fullest extent permitted by law all and

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any responsibility or liability whether arising in tort, contract or otherwise (save as referred to above) which they might otherwise have in respect of this Circular or any such statement.

Important Additional Information

This Circular does not constitute a solicitation of any vote or approval of WestRock Shareholders. Smurfit WestRock has filed with the US SEC a registration statement on Form S-4 (Reg. No. 333-278185) (as amended and as may be further amended or supplemented from time to time, the "US Registration Statement"), which was declared effective by the US SEC on 26 April 2024, that includes a prospectus (the "US Prospectus") relating to the offer and sale of Smurfit WestRock Shares to WestRock Shareholders pursuant to the Merger. In addition, on 26 April 2024, WestRock filed a separate definitive proxy statement with the US SEC with respect to the special meeting of WestRock Shareholders in connection with the Merger (as it may be amended or supplemented from time to time, the "US Proxy Statement"). WestRock commenced mailing of the US Proxy Statement to WestRock Shareholders on or about 1 May 2024. YOU ARE URGED TO READ THE US REGISTRATION STATEMENT AND OTHER DOCUMENTS FILED OR TO BE FILED WITH THE US SEC IN CONNECTION WITH THE COMBINATION CAREFULLY AND IN THEIR ENTIRETY, BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION ABOUT THE COMBINATION, THE PARTIES TO THE COMBINATION, THE RISKS ASSOCIATED WITH THE COMBINATION AND RELATED MATTERS, INCLUDING INFORMATION ABOUT CERTAIN OF THE PARTIES' RESPECTIVE DIRECTORS, EXECUTIVE OFFICERS AND OTHER EMPLOYEES WHO MAY BE DEEMED TO BE PARTICIPANTS IN THE SOLICITATION OF PROXIES IN CONNECTION WITH THE COMBINATION AND ABOUT THEIR INTERESTS IN THE SOLICITATION. The US Registration Statement, the US Prospectus, the US Proxy Statement and other documents filed by Smurfit Kappa, WestRock and Smurfit WestRock with the US SEC are available free of charge at the US SEC's website at www.sec.gov. In addition, investors and shareholders or stockholders are able to obtain free copies of the US Registration Statement, the US Proxy Statement and other documents filed with the US SEC by WestRock online at ir.westrock.com/ir-home/, upon written request delivered to 1000 Abernathy Road, Atlanta, Georgia 30328, United States, or by calling [phone], and are able to obtain free copies of the US Registration Statement, the US Prospectus and other documents filed with the US SEC by Smurfit WestRock or Smurfit Kappa online at www.smurfitkappa.com/investors, upon written request delivered to Beech Hill, Clonskeagh, Dublin 4, D04 N2R2, Ireland or by calling [phone]. The contents of these websites, the US

Registration Statement, the US Proxy Statement, the US Prospectus and other documents filed or to be filed with the US SEC are not incorporated into this Circular by reference and do not form part of this Circular.

The date of publication of this Circular is 14 May 2024.

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TABLE OF CONTENTS
PRESENTATION OF INFORMATION	1
EXPECTED TIMETABLE OF PRINCIPAL EVENTS	7
FAQ REGARDING THE COMBINATION	9
DIRECTORS, SECRETARY, REGISTERED OFFICE AND ADVISERS	18
PART I LETTER FROM THE CHAIR	20
PART II RISK FACTORS	38
PART III PRINCIPAL TERMS AND CONDITIONS OF THE COMBINATION	74
PART IV CHANGES TO THE CORPORATE GOVERNANCE RULES, SECURITIES LAWS AND
COMPANY LAW, AND SUMMARY OF THE DIFFERENCES BETWEEN LISTING CATEGORIES
ON THE OFFICIAL LIST OF THE FCA FOLLOWING THE COMBINATION	106
PART V SETTLEMENT AND DEALINGS IN SMURFIT WESTROCK SHARES FOLLOWING THE
COMBINATION	119
PART VI SUMMARY OF THE TAX CONSEQUENCES OF THE COMBINATION	127
PART VII UNAUDITED PRO FORMA FINANCIAL INFORMATION FOR THE COMBINED
GROUP	141
PART VIII ADDITIONAL INFORMATION	156
PART IX SCHEME OF ARRANGEMENT EXPLANATORY STATEMENT	183
PART X SCHEME OF ARRANGEMENT	189
PART XI DEFINITIONS	197
PART XII NOTICE OF SCHEME MEETING	217
PART XIII NOTICE OF EXTRAORDINARY GENERAL MEETING OF SMURFIT KAPPA GROUP
PUBLIC LIMITED COMPANY	221
PART XIV PROFIT FORECASTS NO LONGER VALID	227
PART XV HISTORICAL FINANCIAL STATEMENTS OF WESTROCK	F-1
APPENDIX I SMURFIT WESTROCK PLC CONSTITUTION	A-1

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PRESENTATION OF INFORMATION

FORWARD-LOOKING STATEMENTS

This Circular, as well as oral statements made or to be made by Smurfit WestRock, Smurfit Kappa and WestRock, include certain "forward-looking statements" (including within the meaning of US federal securities laws) regarding the Combination and the listing of Smurfit WestRock, the rationale and expected benefits of the Combination (including, but not limited to, cost synergies), and any other statements regarding Smurfit WestRock's, Smurfit Kappa's and WestRock's future expectations, beliefs, plans, objectives, results of operations, financial condition and cash flows, or future events or performance. Statements included in this Circular that are not historical facts, including statements about the beliefs and expectations of the management of each of Smurfit WestRock, Smurfit Kappa and WestRock, are forward-looking statements. Words such as "may", "will", "could", "should", "would", "anticipate", "intend", "estimate", "project", "plan", "believe", "expect", "target", "prospects", "potential", "commit", "forecasts", "aims", "considered", "likely", "estimate" and variations of these words and similar future or conditional expressions are intended to identify forward- looking statements but are not the exclusive means of identifying such statements. While Smurfit WestRock, Smurfit Kappa and WestRock believe these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond the control of Smurfit WestRock, Smurfit Kappa and WestRock. By their nature, forward-looking statements involve risk and uncertainty because they relate to events and depend upon future circumstances that may or may not occur. Actual results may differ materially from the current expectations of Smurfit WestRock, Smurfit Kappa and WestRock depending upon a number of factors affecting their businesses and risks associated with the successful execution of the Combination and the integration and performance of their businesses following the Combination. Important factors that could cause actual results to differ materially from such plans, estimates or expectations include:

• developments related to pricing cycles and volumes;
• economic, competitive and market conditions generally, including macroeconomic uncertainty, customer inventory rebalancing, the impact of inflation and increases in energy, raw materials, shipping, labour and capital equipment costs;
• reduced supply of raw materials, energy and transportation, including from supply chain disruptions and labour shortages;
• intense competition;
• risks related to international sales and operations;
• failure to respond to changing customer preferences and to protect intellectual property;
• results and impacts of acquisitions by Smurfit Kappa, WestRock or, following Completion, the Combined Group;
• the amount and timing of Smurfit Kappa's, WestRock's and, following Completion, the Combined Group's capital expenditures;
• evolving legal, regulatory and tax regimes;
• changes in economic, financial, political and regulatory conditions in Ireland, the United Kingdom, the United States and elsewhere, and other factors that contribute to uncertainty and volatility, natural and man-made disasters, civil unrest, pandemics (such as the COVID-19 pandemic), geopolitical uncertainty, and conditions that may result from legislative, regulatory, trade and policy changes associated with the current or subsequent Irish, US or UK administrations;
• the ability of Smurfit Kappa, WestRock or, following Completion the Combined Group, to successfully recover from a disaster or other business continuity problem due to a hurricane, flood, earthquake, terrorist attack, war, pandemic, security breach, cyber-attack, power loss, telecommunications failure or other natural or man-made event, including the ability to function remotely during long-term disruptions such as the COVID-19 pandemic;
• the impact of public health crises, such as pandemics (including the COVID-19 pandemic) and epidemics and any related company or governmental policies and actions to protect the health and safety of individuals or governmental policies or actions to maintain the functioning of national or global economies and markets;
• the potential impairment of assets and goodwill;

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• the scope, costs, timing and impact of any restructuring of operations and corporate and tax structure;
• actions by third parties, including government agencies;
• a Condition to the closing of the Combination may not be satisfied;
• the occurrence of any event that can give rise to termination of the Combination;
• a regulatory approval that may be required for the Combination is delayed, is not obtained in a timely manner or at all or is obtained subject to conditions that are not anticipated;
• Smurfit WestRock may be unable to achieve the synergies and value creation contemplated by the Combination;
• Smurfit WestRock's availability of sufficient cash to distribute to Smurfit WestRock Shareholders in line with current expectations;
• Smurfit WestRock may be unable to promptly and effectively integrate Smurfit Kappa's and WestRock's businesses;
• failure to successfully implement strategic transformation initiatives;
• each of Smurfit Kappa's, WestRock's and, following Completion, the Combined Group's management's time and attention is diverted on issues related to the Combination;
• disruption from the Combination makes it more difficult to maintain business, contractual and operational relationships;
• significant levels of indebtedness;
• credit ratings may decline following the Combination;
• legal proceedings may be instituted against Smurfit WestRock, Smurfit Kappa or WestRock;
• Smurfit Kappa, WestRock and, following Completion the Combined Group, may be unable to retain or hire key personnel;
• the consummation of the Combination may have a negative effect on Smurfit Kappa's or WestRock's share prices, or on their operating results;
• the risk that disruptions from the Combination will harm Smurfit Kappa's or WestRock's business, including current plans and operations;
• certain restrictions during the pendency of the Combination that may impact Smurfit Kappa's or WestRock's ability to pursue certain business opportunities or strategic transactions;
• Smurfit WestRock's ability to meet expectations regarding the accounting and tax treatments of the Combination, including the risk that the Internal Revenue Service (the "IRS") may assert that Smurfit WestRock should be treated as a US corporation or be subject to certain unfavourable US federal income tax rules under Section 7874 of the Code as a result of the Combination; and
• other factors such as future market conditions, currency fluctuations, the behaviour of other market participants, the actions of regulators and other factors such as changes in the political, social and regulatory framework in which the Combined Group will operate or in economic or technological trends or conditions.

Consequently, all of the forward-looking statements Smurfit WestRock, Smurfit Kappa and WestRock make in this Circular are qualified by the information contained in this Circular, including, but not limited to, (i) the information under this heading, (ii) the information discussed in Part II (Risk Factors) of this Circular.

None of Smurfit WestRock, Smurfit Kappa, WestRock or any of their respective associates or directors, officers or advisers provides any representation, assurance or guarantee that the occurrence of the events expressed or implied in any forward-looking statements in this Circular will actually occur. You are cautioned not to place undue reliance on these forward-looking statements. Other than in accordance with its legal or regulatory obligations (including under the UK Prospectus Regulation, the Listing Rules and the DTRs, the Prospectus Regulation Rules, the UK Market Abuse Regulation and other applicable regulations), Smurfit Kappa is under no obligation, and Smurfit Kappa 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.

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Nothing in this paragraph or anywhere else in this Circular should be construed as qualifying the statement in respect of the Combined Group's working capital set out in paragraph 9 of Part VIII (Additional Information) of this Circular. Information in this Circular will be updated as required by the Prospectus Regulation Rules, the Listing Rules and the DTRs, as appropriate.

SYNERGIES INFORMATION

Statements of identified synergies and estimated cost savings relate to future actions and circumstances which by their nature involve risks, uncertainties and contingencies. As a consequence, the identified synergies and estimated cost savings referred to in this document may not be achieved, may be achieved later or sooner than estimated, or those achieved could be materially different from those estimated.

PRESENTATION OF FINANCIAL INFORMATION

Unless otherwise stated:

• financial information included in this Circular relating to Smurfit Kappa has been extracted without material adjustment from the audited consolidated financial statements of Smurfit Kappa as at and for the financial years ended 31 December 2021, 31 December 2022 and 31 December 2023 (the "Smurfit Kappa Annual Financial Statements"), prepared in accordance with US GAAP, which have been published by Smurfit Kappa on or around the date of this Circular; and
• financial information included in this Circular relating to WestRock has been extracted without material adjustment from the audited consolidated financial statements of WestRock for the financial years ended 30 September 2021 (the "WestRock 2021 Annual Financial Statements"), 30 September 2022 (the "WestRock 2022 Annual Financial Statements") and 30 September 2023 (the "WestRock 2023 Annual Financial Statements", and together with the WestRock 2021 Annual Financial Statements and the WestRock 2022 Annual Financial Statements, the "WestRock Annual Financial Statements"), or from the unaudited, interim consolidated financial statements of WestRock as at and for the three months ended 31 December 2023 (the "WestRock Q1 Financial Statements") or as at and for the three and six months ended 31 March 2024 (the "WestRock H1 Financial Statements", and together with the WestRock Q1 Financial Statements and the WestRock Annual Financial Statements, the "WestRock Financial Statements"), each of which is included in Part XV (Historical Financial Statements of WestRock) of this Circular.

Where information in this Circular has been extracted from the audited consolidated financial statements of Smurfit Kappa or the audited consolidated financial statements of WestRock, the information is audited unless otherwise stated. Where information has been extracted from the unaudited, interim consolidated financial statements of WestRock, the information is unaudited.

Unless otherwise indicated, financial information in this document relating to Smurfit Kappa and WestRock has been prepared in accordance with US GAAP.

PRO FORMA FINANCIAL INFORMATION

In this Circular, any reference to pro forma financial information is to information which has been extracted without material adjustments from the unaudited pro forma financial information contained in Part VII (Unaudited Pro Forma Financial Information for the Combined Group). The unaudited pro forma financial information has been prepared for illustrative purposes only and, because of its nature, addresses a hypothetical situation and therefore does not represent the Combined Group's actual financial position or results.

CURRENCIES

Unless otherwise indicated, all references in this Circular to "US dollars", "USD", "US$" or "$" are to the lawful currency of the United States; references to "sterling", "GBP", "£", "pence" or "p" are to the lawful currency of the United Kingdom; references to "EUR", "euro" or "€" are to the official currency of the Eurozone; and references to "R$" are to the lawful currency of Brazil.

ROUNDING

Certain figures contained in this Circular, including financial, statistical and operating information, have been subject to rounding adjustments. Accordingly, in certain instances, the sum of the numbers in a column or row in tables contained in this Circular may not conform exactly to the total figure given for that column or row.

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NON-US GAAP MEASURES

This Circular references Adjusted EBITDA and Consolidated Adjusted EBITDA, which are non-US GAAP measures. These measures are not defined under US GAAP and are presented in this Circular because Smurfit Kappa believes that they provide additional meaningful financial information that may be relevant when assessing the ongoing performance of Smurfit Kappa or WestRock, as applicable. These non-US GAAP financial measures are not intended to be considered in isolation of, as a substitute for, superior to or as an alternative to Smurfit Kappa's and WestRock's respective US GAAP results. These non-US GAAP financial measures may differ from similarly captioned measures presented by other companies.

MARKET AND INDUSTRY INFORMATION

Market data and certain industry forecasts used in this Circular were obtained from internal surveys, reports and studies, where appropriate, as well as market research, publicly available information and industry publications. Industry publications generally state that the information they contain has been obtained from sources believed to be reliable but that the accuracy or completeness of such information is not guaranteed. Similarly, internal surveys, reports and studies and market research, while believed by Smurfit Kappa to be reliable and accurately extracted by Smurfit Kappa for the purposes of this Circular, have not been independently verified and Smurfit Kappa makes no representation as to the accuracy of such information.

TIME

All references in this Circular to times are to UK and Irish times, unless otherwise stated.

DEFINITIONS

Capitalised terms used in this Circular have the meaning ascribed to them in Part XI (Definitions) of this Circular.

NO OFFER OF SECURITIES

This Circular does not constitute or form part of any offer or invitation to purchase, acquire, subscribe for, sell, dispose of or issue, or any solicitation of any offer to sell, dispose of, purchase, acquire or subscribe for, any security, including any Smurfit WestRock Shares to be issued to Smurfit Kappa Shareholders and WestRock Shareholders in connection with the Combination. In particular, the issuance of the Smurfit WestRock Shares in connection with the Combination to Smurfit Kappa Shareholders has not been, and is not expected to be, registered under the US Securities Act or the securities laws of any other jurisdiction. The Smurfit WestRock Shares to be issued in connection with the Combination to Smurfit Kappa Shareholders will be issued pursuant to an exemption from the registration requirements provided by Section 3(a)(10) of the US Securities Act based on the approval of the Scheme by the Irish High Court. Section 3(a)(10) of the US Securities Act exempts securities issued in exchange for one or more bona fide outstanding securities from the general requirement of registration where the fairness of the terms and conditions of the issuance and exchange of the securities have been approved by any court or authorised governmental entity, after a hearing upon the fairness of the terms and conditions of the exchange at which all persons to whom securities will be issued have the right to appear and to whom adequate notice of the hearing has been given. In determining whether it is appropriate to authorise the Scheme, the Irish High Court will consider at the Irish Court Hearing whether the terms and conditions of the Scheme are fair to Scheme Shareholders. The Irish High Court will fix the date and time for the Irish Court Hearing. If the Irish High Court approves the Scheme, its approval will constitute the basis for the Smurfit WestRock Shares to be issued without registration under the US Securities Act in reliance on the exemption from the registration requirements of the US Securities Act provided by Section 3(a)(10) of the US Securities Act. The Smurfit WestRock Shares issued pursuant to Section 3(a)(10) of the US Securities Act will be freely transferable under US federal securities laws, except by any Smurfit Kappa Shareholder who may be deemed an "affiliate" for purposes of Rule 144 of the US Securities Act of Smurfit WestRock after Completion.

In the event that Smurfit WestRock Shares are in fact held by affiliates of Smurfit WestRock, those holders may resell the Smurfit WestRock Shares (a) in accordance with the provisions of Rule 144 under the US Securities Act or (b) as otherwise permitted under the US Securities Act. Rule 144 generally provides that "affiliates" of Smurfit WestRock may not sell securities of Smurfit WestRock received in connection with the Combination unless the sale is effected in compliance with the volume, current public information, manner of sale and timing limitations set forth in such rule. These limitations generally permit sales made by an affiliate in any three-month period that do not exceed the greater of 1% of the outstanding Smurfit WestRock Shares or the average weekly reported trading volume in such securities over the four calendar weeks preceding the

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notice of sale required under Rule 144, provided that the sales are made in unsolicited, open market "brokers' transactions" and that current public information on Smurfit WestRock is available.

PARTICIPANTS IN THE SOLICITATION OF PROXIES

This Circular does not constitute a solicitation of any vote or approval of WestRock Shareholders. However, under US SEC rules, Smurfit Kappa, WestRock, Smurfit WestRock, and certain of their respective directors, executive officers and other members of the management and employees may be deemed to be participants in the solicitation of proxies in connection with the Combination.

Information about (i) WestRock's directors is set forth in the section entitled "Board Composition" on page 8 of WestRock's proxy statement on Schedule 14A filed with the US SEC on December 13, 2023 and

1. WestRock's executive officers is set forth in the section entitled "Executive Officers" on page 141 of WestRock's Annual Report on Form 10-K (the "WestRock 2023 Annual Report") filed with the US SEC on November 17, 2023. Information about the compensation of WestRock's directors for the financial year ended 30 September 2023 is set forth in the section entitled "Director Compensation" starting on page 19 of WestRock's proxy statement on Schedule 14A filed with the US SEC on December 13, 2023. Information about the compensation of WestRock's executive officers for the financial year ended 30 September 2023 is set forth in the section entitled "Executive Compensation Tables" starting on page 38 of WestRock's proxy statement on Schedule 14A filed with the US SEC on December 13, 2023. Transactions with related persons (as defined in Item 404 of Regulation S-K promulgated under the US Securities Act) are disclosed in the section entitled "Certain Relationships and Related Person Transactions" on page 20 of WestRock's proxy statement on Schedule 14A filed with the US SEC on December 13, 2023. Information about the beneficial ownership of WestRock's securities by WestRock's directors and named executive officers as of 22 April 2024 is set forth in the section entitled "Security Ownership of Certain Beneficial Holders, Directors and Management of WestRock" starting on page 277 of each of the US Proxy Statement and the US Prospectus. As of 22 April 2024, none of the participants (within the meaning of Rule 13d-3 under the US Exchange Act) owned more than 1% of WestRock Shares. Other information regarding certain participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise are contained in the section entitled "Interests of WestRock's Directors and Executive Officers in the Combination" beginning on page 139 of each of the US Prospectus and the US Proxy Statement.

Information about Smurfit Kappa's directors and executive officers is set forth in the section entitled "Board of Directors," starting on page 112 of Smurfit Kappa's 2023 Annual Report (the "Smurfit Kappa 2023 Annual Report") published on Smurfit Kappa's website on 15 March 2024 which was filed with the FCA on 15 March 2024 and Euronext Dublin in Ireland on 15 March 2024. Information about the compensation of Smurfit Kappa executive officers and directors is set forth in the remuneration report starting on page 129 of the Smurfit Kappa 2023 Annual Report. Transactions with related persons (as defined under Paragraph 24 of the International Accounting Standards) are disclosed in the subsection entitled "Related Party Transactions" to the section entitled "Notes to the Consolidated Financial Statements," on page 223 of the Smurfit Kappa 2023 Annual Report. Information about the beneficial ownership of Smurfit Kappa's securities by Smurfit Kappa's directors and executive officers is set forth in the section entitled "Executive Directors' Interests in Share Capital at 31 December 2023," on page 147 of the Smurfit Kappa 2023 Annual Report.

Information about the expected beneficial ownership of Smurfit WestRock securities by the individuals who are expected to be executive officers and directors of Smurfit WestRock at Completion is set forth in the section entitled "Security Ownership of Certain Beneficial Holders, Directors and Management of Smurfit WestRock" beginning on page 279 of each of the US Prospectus and the US Proxy Statement. Information required by Item 402 of the SEC's Regulation S-K with respect to the executive officers of Smurfit WestRock who served as executives of Smurfit Kappa during Smurfit Kappa's fiscal year 2023, as well as a description of certain post-Completion compensation arrangements that are expected to apply to the executive officers of Smurfit WestRock, is set forth in the section entitled "Executive Compensation" beginning on page 327 of each of the US Prospectus and the US Proxy Statement.

NO PROFIT FORECASTS OR ESTIMATES

No statement in this Circular is intended to be or is to be construed as a profit forecast or estimate for any period and no other statement in this Circular should be interpreted to mean that earnings or earnings per share for Smurfit Kappa or WestRock for the current or future financial years, or those of the Combined Group, would necessarily match or exceed the historical published earnings or earnings per share for Smurfit Kappa or WestRock.

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PROFIT FORECASTS NO LONGER VALID

Certain long-range, unaudited Projections (as defined in Part XIV (Profit Forecasts No Longer Valid) of this Circular) regarding Smurfit Kappa's and WestRock's future performance (in each case, on a stand-alone basis without giving effect to the Combination) have been included in the US Registration Statement and the US Proxy Statement. The requirement for the Projections to be included within the US Registration Statement and the US Proxy Statement arose in connection with certain opinions produced by each of Evercore and Lazard, WestRock's financial advisers, on the fairness, from a financial point of view, of the Merger Consideration offered to WestRock Shareholders. As part of that disclosure, WestRock was required to disclose the Projections in the US Registration Statement and the US Proxy Statement. For the reasons set out in Part XIV (Profit Forecasts No Longer Valid) of this Circular, Smurfit Kappa considers that the Projections are no longer valid and does not consider reassessment of the Projections to be necessary.

NO REPRESENTATIONS

The summary of the Transaction Agreement and its terms contained in this Circular has been included in order to provide investors with information regarding the principal terms of the Transaction Agreement and is qualified in its entirety by reference to the Transaction Agreement. Except for the status of the Transaction Agreement as a contractual document that establishes and governs the legal relations among the parties thereto with respect to the transactions related thereto, the Transaction Agreement is not intended to be a source of factual, business or operational information about the parties. The representations, warranties and covenants made by the parties in the Transaction Agreement are made solely for the benefit of the parties to such agreement and are qualified, including by information in disclosure schedules that the parties exchanged in connection with the execution of such agreement. Representations and warranties may be used as a tool to promote disclosure and allocate risks between the parties, including where the parties do not have complete knowledge of all facts. Smurfit Kappa Shareholders are not third party beneficiaries under the Transaction Agreement and should not rely on the representations, warranties and covenants or any descriptions thereof as characterisations of the actual state of facts or conditions of Smurfit Kappa, WestRock, Smurfit WestRock or any of their affiliates or subsidiaries.

WEBSITES

The contents of Smurfit Kappa's, WestRock's or Smurfit WestRock's websites, or of any website accessible via hyperlinks from Smurfit Kappa's, WestRock's or Smurfit WestRock's websites, are not incorporated into, and do not form part of, this Circular.

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