Harbour Energy PLC — Proxy Solicitation & Information Statement 2020

Dec 16, 2020

PREMIER OIL PLC (THE "COMPANY") – GENERAL MEETING

To be held at 23 Lower Belgrave Street, London, SW1W 0NR at 2 p.m. on 12 January 2021.

You may submit your proxy electronically at www.premier-oil-shares.com (see note 7 overleaf). If you have not previously registered, you will need your Investor Code shown below.

In view of the current COVID-19 restrictions, physical attendance at the General Meeting will not be possible. Accordingly, your Board strongly encourages you to vote electronically or to vote by proxy. You can cast your vote online at www.premier-oil-shares.com or by post using the proxy card below. We understand that the General Meeting is an opportunity for shareholders to ask questions of the Board in relation to the business of the General Meeting and the Company's operations. We are keen to ensure that this dialogue continues, even though we face challenging external circumstances. The Company will therefore be accepting questions for the General Meeting via email (investor.relations@premier-oil.com) or, alternatively, we would be happy to receive written questions by post sent to our Registrar, Link Asset Services. Any questions to be put to the General Meeting should be submitted by the close of business on Friday 8 January 2021.

FORM OF PROXY PREMIER OIL PLC – GENERAL MEETING

Event Code:

Barcode:

Investor Code:

Number of shares:

I/We being a member of the Company hereby appoint the Chairman of the General Meeting (see note 1 overleaf) as my/our proxy to exercise all or any of my/our rights to vote in respect of my/our voting entitlement on my/our behalf at the General Meeting of the Company to be held at 23 Lower Belgrave Street, London, SW1W 0NR at 2 p.m. on 12 January 2021 and at any adjournment thereof. On any motion to amend any resolution, to propose a new resolution, to adjourn the meeting or any other motion put to the meeting, the proxy will act at his discretion.

I/We have indicated with an "X" how I/we wish my/our votes to be cast on the following resolution:

Resolutions Please mark "X" to indicate how you wish to vote.

ORDINARY RESOLUTIONS Please mark 'X' to indicate

how you wish to vote

• ¹To approve the proposed merger of Chrysaor and the Company X X X
• ²To approve the waiver granted by the Takeover Panel in respect of the Rule 9 obligations which may otherwise arise X X X
• 3 To authorise the Directors to allot relevant securities pursuant to Section 551 of the Companies Act in connection with the Merger and Debt Restructuring X X X
• ⁴To approve the Subdivision of existing Ordinary Shares into Ordinary Shares and Non-Voting Deferred Shares X X X
• 5 To authorise the Directors to allot relevant securities pursuant to Section 551 of the Companies Act in substitution for the similar authority provided at the 2020 AGM X X X

SPECIAL RESOLUTIONS

• 6 To authorise the Directors to disapply pre-emption rights (under section 561 of the Companies Act) in respect of the Merger and Debt Restructuring X X X
• 7 To authorise the Directors to disapply pre-emption rights (under section 561 of the Companies Act) in substitution for the similar authority provided at the 2020 AGM X X X

Signature Date

For

Against

Vote Withheld

You may submit your proxy electronically at www.premier-oil-shares.com

Premier Oil plc – General Meeting

To be held at 23 Lower Belgrave Street, London, SW1W 0NR at 2 p.m. on 12 January 2021.

Notes:

• 1. Please indicate in the 'number of shares' box the shares you would like the Chairman to vote on your behalf (which, in aggregate, should not exceed the number of shares held by you). If the box is left blank, all the shares registered in your name will be cast in accordance with your instructions.
• 1. CREST members should refer to the Notice of General Meeting for instructions regarding the CREST electronic proxy appointment service.
• 1. Please indicate with a mark in the boxes opposite the resolution how you wish the proxy to vote on your behalf. In the absence of instructions, the person appointed proxy may vote or refrain from voting as he thinks fit on the resolution and, unless instructed otherwise, the person appointed proxy may also vote or refrain from voting as he thinks fit on any other business (including amendments to the resolution) which may properly come before the meeting.
• 1. The "Withheld" option is provided to enable you to refrain from voting on the resolution. However, it should be noted that a vote "Withheld" is not a vote in law and will not be counted in the calculation of the proportion of the votes "For" and "Against" the resolution.
• 1. This form must be signed and dated by the shareholder or his/her attorney duly authorised in writing. If the shareholder is a company, it may execute by the signature(s) of a duly authorised officer or attorney. In the case of joint holdings, any one holder may sign this form. The vote of the senior joint holder who tenders a vote, whether in person or by proxy, will be accepted to the exclusion of the votes of the other joint holders and for this purpose seniority will be determined by the order in which the names stand in the Register of Members in respect of the joint holding.
• 1. To be valid, this form of proxy, together with any power of attorney under which it is signed, should be returned to the Company's Registrar at Link Asset Services, PXS 1, 34 Beckenham Road, Beckenham, BR3 4TU, by not later than 2 p.m. on Friday 8 January 2021 (or in the case of an adjournment, not later than 48 hours before the time fixed for the holding of the adjournment meeting). You may also deliver this form of proxy by hand to Link Asset Services, PXS 1, 34 Beckenham Road, Beckenham, BR3 4ZF during usual business hours.
• 1. You can submit your proxy via the internet by accessing www. premier-oil-shares.com. You will need your Investor Code to log in. Before you can submit your proxy you will be asked to agree certain terms and conditions. You will be issued with confirmation of your voting once the process is complete.
• 1. To be entitled to vote at the meeting, shareholders' names must be entered on the Register of Members at close of business on Friday 8 January 2021.
• 1. If you prefer, you may return the proxy form to Link Asset Services in an envelope addressed to FREEPOST PXS 1, 34 Beckenham Road, BR3 9ZA. Please note delivery using this service may take up to 5 business days.

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