OSH & STO Merger Update

For personal use only

11 November 2021

Oil Search and Santos merger update: Court approves distribution of Scheme Booklet and convening of Scheme Meeting

• The Independent Expert has concluded that the Merger is in the best interests of Oil Search shareholders in the absence of a superior proposal
• The Oil Search Board continues to unanimously recommend that Oil Search shareholders vote in favour of the Scheme at the Scheme Meeting in the absence of a superior proposal

Oil Search Limited ("Oil Search") and Santos Limited ("Santos") are pleased to provide the following update in relation to their proposed merger announced to the ASX on 10 September 2021. As set out in that announcement, the Merger is proposed to be effected by a scheme of arrangement under PNG law whereby Santos will acquire all of the shares in Oil Search and Oil Search shareholders will receive 0.6275 new Santos shares for each Oil Search share ('the Scheme").

The National Court of Papua New Guinea ("PNG") has today made orders:

• that Oil Search convene a meeting of Oil Search shareholders on Tuesday 7 December 2021, to consider and vote on the proposed Scheme ("Scheme Meeting"); and
• approving the distribution to Oil Search shareholders of an explanatory statement providing information about the Scheme and notice of the Scheme Meeting ("Scheme Booklet").

Scheme Booklet

A copy of the Scheme Booklet, and a Notice of Scheme Meeting, is attached to this announcement.

The Scheme Booklet provides Oil Search shareholders with information about the Scheme.

The Scheme Booklet includes a copy of the Independent Expert's Report prepared by Grant Samuel & Associates Pty Limited ("Independent Expert").

The Independent Expert has concluded that the Merger is in the best interests of Oil Search shareholders in the absence of a superior proposal. A complete copy of the Independent Expert's Report is included in Annexure A to the Scheme Booklet. Oil Search shareholders should carefully review the Independent Expert's Report in its entirety.

Directors' recommendation

The Oil Search Board continues to unanimously recommend that Oil Search shareholders vote in favour of the Scheme at the Scheme Meeting in the absence of a superior proposal. Each Oil Search Director intends to vote all the Oil Search shares held or controlled by them in favour of the Scheme, in the absence of a superior proposal.

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Oil Search Chairman, Rick Lee, said "The Merger brings together two highly complementary businesses and creates an oil and gas company of significant size with a portfolio of geographically and product diversified long-life and low-cost assets. We look forward to Oil Search's shareholders participation in the Scheme Meeting and encourage you to vote in favour of the Merger, which the Oil Search Directors believe, is in the best interests of Oil Search shareholders."

Santos Chairman, Keith Spence, said "The merger represents an attractive combination of two industry leaders to create a regional champion with the balance sheet and strong diversified cashflows necessary to fund growth, the energy transition to a lower carbon future including Santos' leading carbon capture and storage capability, and deliver shareholder returns.

"We look forward to integrating our businesses to create one high performing team - with a vision of becoming a global leader in the energy transition," Mr Spence said.

Accessing the Scheme Booklet

Oil Search shareholders who have previously elected to receive communications electronically will receive an email to their nominated email address during the course of this week, that will contain instructions about how to view or download a copy of the Scheme Booklet. Oil Search shareholders who have not made such an election will receive a letter (sent by post to their registered address) containing details of where they can view and download the Scheme Booklet.

Oil Search shareholders who wish to receive a printed copy of the Scheme Booklet may request one by calling the Oil Search Shareholder Information Line on 1300 150 530 (within Australia) or [phone] (outside Australia), Monday to Friday between 9:00am and 5:00pm (Sydney time) other than public holidays in Sydney, Australia.

Oil Search shareholders are advised to read the Scheme Booklet in its entirety before making a decision on whether or not to vote in favour of the Scheme.

Scheme Meeting

The Scheme Meeting will be conducted as a virtual meeting at 11:00am (Sydney time) / 10:00am (Port Moresby time) on Tuesday, 7 December 2021. There will be no physical Scheme Meeting. Oil Search shareholders (or their proxies, attorneys or corporate representatives) will be able to attend and vote at the Scheme Meeting through an online platform available at https://web.lumiagm.com/399778470(meeting ID 399778470).

All Oil Search shareholders are encouraged to vote either by attending and voting at the virtual Scheme Meeting or by lodging a proxy to attend and vote at the virtual Scheme Meeting. The Notice of Scheme Meeting provides information on how to lodge your Proxy Form (if applicable).

Queries

If Oil Search shareholders have any questions in relation to this Scheme Booklet or the Scheme, they can call the Oil Search Shareholder Information Line on 1300 150 530 (within Australia) or [phone] (outside Australia), Monday to Friday between 9:00am and 5:00pm (Sydney time) other than public holidays in Sydney, Australia. If you are not able to

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access the Oil Search Shareholder Information Line you can request a call back from [e-mail] you can view further information at

https://www.oilsearch.com/scheme-meeting.

This ASX announcement was approved and authorised for release by Peter Fredricson, Acting Chief Executive Officer of Oil Search and Kevin Gallagher, Managing Director and Chief Executive Officer of Santos.

Oil Search Limited ARBN 055 079 868	Media enquiries	Investor enquiries
GPO Box 2442, Sydney NSW 2001	Ian Pemberton	Narelle Checchin
T [phone] F [phone]	[phone]	[phone]
oilsearch.com	[e-mail]	[e-mail]

Santos Limited ABN 80 007 550 923	Media enquiries	Investor enquiries
GPO Box 2455, Adelaide SA 5001	James Murphy	Andrew Nairn
T [phone] F [phone]	[phone]	[phone]
www.santos.com	[e-mail]	[e-mail]

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Oil Search Limited (ARBN 055 079 868)

SCHEME BOOKLET

In relation to the proposed merger of Oil Search Limited (Oil Search)

and Santos Limited (Santos) by way of Scheme of Arrangement

VOTE IN FAVOUR

Your Directors unanimously recommend that you VOTE IN FAVOUR

of the Scheme in the absence of a Superior Proposal

For personal use only

This Scheme Booklet is important and requires your prompt attention. You should read it in its entirety, and consider its contents carefully, before deciding whether or not to vote in favour of the Scheme. If you are in any doubt about what you should do, you should consult with a financial, legal, taxation or other professional adviser.

If you have any questions in relation to this Scheme Booklet or the Scheme, please contact the Oil Search Shareholder Information Line on 1300 150 530 (within Australia) or [phone] (outside Australia), Monday to Friday between 9:00am and 5:00pm (Sydney time) other than public holidays in Sydney, Australia.

Financial Advisers		Legal Advisers

Oil Search Limited  Scheme Booklet

Important notices

Nature of this Scheme Booklet

This Scheme Booklet is prepared for persons shown in the Oil Search Share Register as holding Oil Search Shares. If you have recently sold all of your Oil Search Shares, please disregard this Scheme

onlyBooklet.

This Scheme Booklet provides Oil Search Shareholders with information about a proposed scheme of arrangement under which Santos will acquire all of the issued share capital in Oil Search, subject to the relevant conditions precedent being satisfied or waived (where capable of waiver), including shareholder, regulatory and court approvals, as explained in this booklet. You should review all of the information in this Scheme Booklet carefully. Section 1.1 sets out the reasons why you should vote in favour of the Scheme and section

1.2 sets out the reasons why you may wish to vote useagainst the Scheme.

D fined terms

A number of defined terms are used in this Scheme Booklet. These terms are explained in section 10 of this Scheme Booklet. Some of the documents reproduced in the annexures to this Scheme Booklet have their own defined terms, which are sometimes different to those set out in section 10.

No investment advice

The information contained in this Scheme Booklet personaldoes not constitute financial product advice and has

been prepared without reference to your individual investment objectives, financial situation, taxation position or particular needs. It is important that you read this Scheme Booklet in its entirety before making any decision as to whether or not to vote in favour of the Scheme or to deal in your Oil Search Shares. If you are in any doubt in relation to these matters, you should consult with a financial, legal, taxation or other professional adviser.

N t an offer

This Scheme Booklet does not constitute or contain an offer to Oil Search Shareholders, or a olicitation of an offer from Oil Search Shareholders, in any jurisdiction.

Regulatory information

This Scheme Booklet is an explanatory statement for the scheme of arrangement between Oil Search and the Scheme Shareholders for the purposes of section 250(2)(a) of the PNG Companies Act. A co y of the proposed Scheme is included in this Scheme Booklet in Annexure C.

Notice of Scheme Meeting

The Notice of Meeting is set out in Annexure E.

ForOil Search's Shareholder's right to appear at the Second Court Hearing

At the Second Court Hearing, the Court will

c nsider whether to approve the Scheme following the vote at the Scheme Meeting.

Any Oil Search Shareholder may appear at the Second Court Hearing, expected to be held in Port Moresby, National Capital District on Thursday, 9 December 2021 at the National Court of Justice of Papua New Guinea at Waigani, Port Moresby, PNG.

Any Oil Search Shareholder who wishes to oppose approval of the Scheme at the Second Court Hearing may seek to do so by filing with the Court and serving on Oil Search

a notice of appearance in the prescribed form together with any affidavit that the Oil Search Shareholder proposes to rely on and subject to any Court direction.

It is possible that, because of restrictions imposed in response to the COVID-19 pandemic, the Second Court Hearing will be (or will also be) conducted by remote access technology, including via a dedicated video conferencing service or telephone conferencing. Any change to the date or arrangements for the conduct of the Second Court Hearing will be announced on the ASX website (www.asx.com.au), the PNGX website (https://www.pngx.com.pg/) and will also be notified on Oil Search's Website.

Important notice associated with the Court Order under section 250(2)(b) of the PNG Companies Act

The fact that under section 250(2)(b) of the PNG Companies Act, the Court has ordered that a meeting be convened and has directed that an explanatory statement accompany the Notice of Meeting does not mean that the Court:

• has formed any view as to the merits of the proposed Scheme or as to how members should vote (members must reach their own decision on this matter); or
• has prepared, or is responsible for, the content of the explanatory statement.

Disclaimer as to forward-looking statements

Certain statements appearing in this Scheme Booklet (including in the Independent Expert's Report) may be in the nature of forward-looking statements. Forward-looking statements generally may be identified by the use of forward-looking words such as "believe", "aim", "expect", "anticipate", "intending", "foreseeing", "likely", "should", "planned", "may", "estimate", "potential", or other similar words. Similarly, statements that describe the objectives, plans, goals, intentions or expectations of Oil Search, Santos or the Merged Group are or may be forward- looking statements.

Forward-looking statements should not be taken to be forecasts or predictions that events will occur or that objectives, plans, goals, intentions or expectations will be achieved. Such statements are only opinions and are subject to inherent risks and uncertainties. Those risks and uncertainties include factors and risks specific to Oil Search, Santos, the Merged Group and/or the industries in which they operate, as well as general economic conditions, prevailing exchange rates and interest rates and conditions in financial markets. Actual events or results may differ materially from the events or results expressed or implied in any forward-looking statement and deviations are both normal and to be expected. Neither Oil Search nor Santos, nor any of their respective affiliates, officers, directors, employees or advisers or any person named in this Scheme Booklet or involved in the preparation of this Scheme Booklet makes any representation or warranty (either express or implied) as to the accuracy or likelihood of fulfilment of any forward-looking statement, or any events or results expressed or implied in any forward-looking statement. Accordingly, you are cautioned not to place undue reliance on those statements.

The forward-looking statements in this Scheme Booklet reflect opinions held only at the date of this Scheme Booklet. Subject to any continuing obligations under relevant laws, the ASX Listing Rules or PNGX Listing Rules, Oil Search, Santos and their respective affiliates, officers, directors, employees and advisers, disclaim any obligation or undertaking to update or revise any such statements after the date of this Scheme Booklet, to reflect any change in expectations in relation to such statements or any change in events, conditions or circumstances on which any such statement is based.

Responsibility statement

Oil Search has prepared, and is responsible for, the Oil Search Information. Neither Santos nor any of its affiliates, officers, directors, employees or advisers assumes any responsibility for the accuracy or completeness of such information.

Santos has prepared, and is responsible for, the Santos Information. Neither Oil Search nor any of its affiliates, officers, directors, employees or advisers assumes any responsibility for the accuracy or completeness of such information.

Grant Samuel has prepared the Independent Expert's Report (including the Independent Technical Expert's Report) and the Independent Expert takes responsibility for that report. Neither Oil Search nor Santos, nor any of their respective affiliates, officers, directors, employees or advisers assume any responsibility for the accuracy or completeness of the information contained in

the Independent Expert's Report (including the Independent Technical Expert's Report). The Independent Expert's Report (including the Independent Technical Expert's Report) is set out in Annexure A.

Ernst & Young as Investigating Accountant has prepared the Investigating Accountant's Report in relation to the Scheme and Investigating Accountant takes responsibility for that report. Neither Oil Search nor Santos, nor any of their respective affiliates, officers, directors, employees or advisers assume any responsibility for the accuracy or completeness of the information contained in the Investigating Accountant's Report. The Investigating Accountant's Report is set out in Annexure B.

Computershare has had no involvement in the preparation of any part of this Scheme Booklet other than being named as the Oil Search Share Registry. Computershare has not authorised or caused

the issue of, and expressly disclaims and takes no responsibility for, any part of this Scheme Booklet.

Foreign jurisdictions

The release, publication or distribution of this Scheme Booklet in jurisdictions other than PNG, Australia, New Zealand, Hong Kong, Malaysia, Singapore, the United Kingdom, Ireland and the United States of America may be restricted by law or regulation in such other jurisdictions. Persons outside of PNG, Australia, New Zealand, Hong Kong, Malaysia, Singapore, the United Kingdom, Ireland and the United States of America who come into possession of this Scheme Booklet should seek advice on and observe any such restrictions. Any failure to comply with such restrictions

may constitute a violation of applicable laws or regulations.

This Scheme Booklet has been prepared in accordance with PNG law and the information contained in this Scheme Booklet may not be the same as that which would have been disclosed if this Scheme Booklet had been prepared in accordance with the laws and regulations outside of PNG. This Scheme Booklet and the Scheme do not constitute an offer of securities in any place in which, or to any person to whom, it would not be lawful to make such an offer.

A Scheme Shareholder whose address shown in the Oil Search Share Register is a place outside of Australia (including its external territories), New Zealand, PNG, Hong Kong, Malaysia, Singapore, the United Kingdom, Ireland and the United States of America as at the Record Date will be an Ineligible Foreign Shareholder.

Oil Search Limited  Scheme Booklet