Sintana Energy Inc.

Major Shareholding Notification • Oct 28, 2025

National Storage Mechanism | Additional information

RNS Number : 1799F

Sintana Energy Inc

28 October 2025

FORM 8 (OPD)

PUBLIC OPENING POSITION DISCLOSURE BY A PARTY TO AN OFFER

Rules 8.1 and 8.2 of the Takeover Code (the "Code")

1.         KEY INFORMATION

(a) Full name of discloser:	Sintana Energy, Inc
(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	Challenger Energy Group
(d) Is the discloser the offeror or the offeree?	OFFEROR
(e) Date position held:      The latest practicable date prior to the disclosure	27 October 2025
(f)  In addition to the company in 1(c) above, is the discloser making disclosures in respect of any other party to the offer?      If it is a cash offer or possible cash offer, state "N/A"	YES - Sintana Energy Inc

2.         POSITIONS OF THE PARTY TO THE OFFER MAKING THE DISCLOSURE

If there are positions or rights to subscribe to disclose in more than one class of relevant securities of the offeror or offeree named in 1(c), copy table 2(a) or (b) (as appropriate) for each additional class of relevant security.

(a)        Interests and short positions in the relevant securities of the offeror or offeree to which the disclosure relates

Class of relevant security:	Ordinary Shares
	Interests		Short positions
Number	%	Number	%
(1) Relevant securities owned and/or controlled:	Nil	-	nil	-
(2) Cash-settled derivatives:	Nil	-	nil	-
(3) Stock-settled derivatives (including options) and agreements to purchase/sell:	Nil	-	nil	-
TOTAL:	Nil	-	nil	-

All interests and all short positions should be disclosed.

Details of 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 (Open Positions).

Details of any securities borrowing and lending positions or financial collateral arrangements should be disclosed on a Supplemental Form 8 (SBL).

(b)        Rights to subscribe for new securities

Class of relevant security in relation to which subscription right exists:
Details, including nature of the rights concerned and relevant percentages:

3.         POSITIONS OF PERSONS ACTING IN CONCERT WITH THE PARTY TO THE OFFER MAKING THE DISCLOSURE

Details of any interests, short positions and rights to subscribe (including directors' and other employee options) of any person acting in concert with the party to the offer making the disclosure:

(a)   Interests held by Charlestown, their directors, close relatives and related trusts:

Name	Common Shares	% of ISC
Charlestown Energy Partners LLC	9,000,000	3.61%

(b)   Options and warrants held by Charlestown and their directors:

Type of Award / Share Plan	Name	Warrants	Options	Ratio	Exercise Price	Date of Grant	Expiry Date
N/A	Charlestown Energy Partners LLC	2,100,000	-	1:1	10p	22/05/24	28/05/26
Board & Executive / Staff Options	Robert Bose*	-	370,000	-	8p	04/11/24	04/11/29
Board & Executive / Staff Options	Robert Bose*	-	370,000	-	12p	04/11/24	04/11/29
Board & Executive / Staff Options	Robert Bose*	-	370,000	-	18p	04/11/24	04/11/29
Board & Executive / Staff Options	Robert Bose*	-	370,000	-	24p	04/11/24	04/11/29

*Robert Bose is a Principal and Managing Member of Charlestown Energy Partners

NB. 50% of Robert Bose's options became exercisable immediately upon the date of grant and 50% become exercisable on 1 March 2026, unless accelerated in accordance with their terms.

Details of 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 (Open Positions).

Details of any securities borrowing and lending positions or financial collateral arrangements should be disclosed on a Supplemental Form 8 (SBL).

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 party to the offer making the disclosure or any person acting in concert with it: 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

Details of any agreement, arrangement or understanding, formal or informal, between the party to the offer making the disclosure, or any person acting in concert with it, and any other person relating to: (i)  the voting rights of any relevant securities under any option; or (ii) the voting rights or future acquisition or disposal of any relevant securities to which any derivative is referenced: If there are no such agreements, arrangements or understandings, state "none"
None

(c)        Attachments

Are any Supplemental Forms attached?

Supplemental Form 8 (Open Positions)	NO
Supplemental Form 8 (SBL)	NO

###### Date of disclosure:	28 October 2025
###### Contact name:	Robert Bose
###### Telephone number:	+1 646 322 4688

Public disclosures under Rule 8 of the Code must be made to a Regulatory Information Service.

The Panel's Market Surveillance Unit is available for consultation in relation to the Code's disclosure requirements on +44 (0)20 7638 0129.

The Code can be viewed on the Panel's website at www.thetakeoverpanel.org.uk .

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