Form of Proxy - Special Meeting to be held on September 12, 2023 01XMYB This Form of Proxy is solicited by and on behalf of Management. Fold Fold CONTROL NUMBER VOTE USING THE TELEPHONE OR INTERNET 24 HOURS A DAY 7 DAYS A WEEK! To vote by telephone or the Internet, you will need to provide your CONTROL NUMBER listed below. If you vote by telephone or the Internet, DO NOT mail back this proxy. Voting by mail may be the only method for securities held in the name of a corporation or securities being voted on behalf of another individual. Voting by mail or by Internet are the only methods by which a holder may appoint a person as proxyholder other than the Management Nominees named on the reverse of this proxy. Instead of mailing this proxy, you may choose one of the three voting methods outlined above to vote this proxy. Notes to proxy 1. Every holder has the right to appoint some other person or company of their choice, who need not be a holder, to attend and act on their behalf at the meeting or any adjournment or postponement thereof. If you wish to appoint a person or company other than the Management Nominees whose names are printed herein, please insert the name of your chosen proxyholder in the space provided (see reverse). 2. If the securities are registered in the name of more than one owner (for example, joint ownership, trustees, executors, etc.), then all those registered should sign this proxy. If you are voting on behalf of a corporation or another individual you may be required to provide documentation evidencing your power to sign this proxy with signing capacity stated. 3. This proxy should be signed in the exact manner as the name(s) appear(s) on the proxy. 4. If a date is not inserted in the space provided on the reverse of this proxy, it will be deemed to bear the date on which it was mailed to the holder by Management. 5. The securities represented by this proxy will be voted as directed by the holder, however, if such a direction is not made in respect of any matter, and the proxy appoints the Management Nominees listed on the reverse, this proxy will be voted as recommended by Management. 6. The securities represented by this proxy will be voted in favour, or withheld from voting, or voted against each of the matters described herein, as applicable, in accordance with the instructions of the holder, on any ballot that may be called for. If you have specified a choice with respect to any matter to be acted on, the securities will be voted accordingly. 7. This proxy confers discretionary authority in respect of amendments or variations to matters identified in the Notice of Meeting and Management Information Circular or other matters that may properly come before the meeting or any adjournment or postponement thereof, unless prohibited by law. 8. This proxy should be read in conjunction with the accompanying documentation provided by Management. Proxies submitted must be received by 4:00 pm (Toronto time), on September 8, 2023. 8th Floor, 100 University Avenue Toronto, Ontario M5J 2Y1 www.computershare.com To Vote Using the Telephone • Call the number listed BELOW from a touch tone telephone. To Vote Using the Internet • Go to the following web site: www.investorvote.com • Smartphone? Scan the QR code to vote now. To Vote by Fax • Complete, sign and date the reverse hereof. • Forward it by fax to 1-866-249-7775 for calls within Canada and the U.S. There is NO CHARGE for this call. • Forward it by fax to 416-263-9524 for calls outside Canada and the U.S. Mr A Sample Designation (if any) Add1 Add2 add3 add4 add5 add6 C1234567890 XXX 000001 COMMON SHARES CPUQC01.E.INT/000001/i1234 123456789012345 Holder Account Number Security Class 1-866-732-VOTE (8683) Toll Free

356765 01XMZB Fold Fold AR0 Signature of Proxyholder I/We authorize you to act in accordance with my/our instructions set out above. I/We hereby revoke any proxy previously given with respect to the meeting. If no voting instructions are indicated above, and the proxy appoints the Management Nominees, this Proxy will be voted as recommended by Management. MM / DD / YY Signature(s) Date 1. Approval of Arrangement Resolution To consider and, if deemed advisable, to pass, with or without variation, pursuant to an interim order of the Supreme Court of British Columbia dated August 11, 2023, a special resolution (the “Arrangement Resolution”), the full text of which is set forth in “Schedule “C” – Arrangement Resolution” to the accompanying management information circular (the “Circular”), approving a plan of arrangement under Division 5 of Part 9 of the Business Corporations Act (British Columbia), involving, among others, the Corporation, Hut 8 Holdings Inc., its direct wholly-owned subsidiary existing under the laws of British Columbia, and Hut 8 Corp., a Delaware corporation (“New Hut”), in accordance with the terms of the business combination agreement dated February 6, 2023 by and among the Corporation, U.S. Data Mining Group, Inc., a Nevada corporation doing business as “US Bitcoin Corp” (“USBTC”), and New Hut (the “Business Combination Agreement”). For Against 2. Approval of New Hut Shares To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “D” – New Hut Resolution” to the accompanying Circular, to authorize the issuance of up to 49,665,834 shares of common stock of New Hut (the “New Hut Shares”), consisting of: (i) up to 44,161,669 New Hut Shares issuable to USBTC stockholders pursuant to the Business Combination Agreement and up to 4,530,326 New Hut Shares issuable upon the exercise of USBTC replacement options to be issued to USBTC stockholders in exchange for their USBTC options outstanding immediately prior to the Merger Effective Time (as defined under the Circular), which figures represent approximately 50% of the common stock of New Hut expected to be outstanding upon completion of the Business Combination (as defined under the Circular), and (ii) and up to 973,839 New Hut Shares, which represents an additional 2% buffer to account for clerical and administrative matters (the “New Hut Resolution”). For Against 3. Approval of the adoption of the New Hut incentive plan To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “E” – Incentive Plan Resolution” to the accompanying Circular, to approve the adoption of the New Hut incentive plan (the “Incentive Plan Resolution”, together with the Arrangement Resolution and New Hut Resolution, the “Hut 8 Resolutions”). For Against I/We being holder(s) of securities of Hut 8 Mining Corp. (the “Corporation”) hereby appoint: Jaime Leverton, or failing this person, Shenif Visram, or failing this person, Aniss Amdiss (the “Management Nominees”) Appointment of Proxyholder Print the name of the person you are appointing if this person is someone other than the Management Nominees listed herein. OR as my/our proxyholder with full power of substitution and to attend, act and to vote for and on behalf of the holder in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and on all other matters that may properly come before the Special Meeting of shareholders of the Corporation to be held at Bennett Jones LLP, 3400 One First Canadian Place, Toronto, ON M5X 1A4 on September 12, 2023 at 10:00 am (Toronto time), and at any adjournment or postponement thereof. VOTING RECOMMENDATIONS ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. C1234567890 XXX 123 MR SAM SAMPLE ORJQ XXXX 999999999999

Voting Instruction Form (“VIF”) - Special Meeting to be held on September 12, 2023 01XMWB This VIF is solicited by and on behalf of Management. Fold Fold CONTROL NUMBER VOTE USING THE TELEPHONE OR INTERNET 24 HOURS A DAY 7 DAYS A WEEK! To vote by telephone or the Internet, you will need to provide your CONTROL NUMBER listed below. If you vote by telephone or the Internet, DO NOT mail back this VIF. Voting by mail may be the only method for securities held in the name of a corporation or securities being voted on behalf of another individual. Voting by mail or by Internet are the only methods by which a holder may appoint a person as proxyholder other than the Management Nominees named on the reverse of this VIF. Instead of mailing this VIF, you may choose one of the three voting methods outlined above to vote this VIF. Notes 1. Every holder has the right to appoint some other person or company of their choice, who need not be a holder, to attend and act on their behalf at the meeting or any adjournment or postponement thereof. If you wish to appoint a person or company other than the Management Nominees whose names are printed herein, please insert the name of your chosen proxyholder in the space provided (see reverse). 2. If the securities are registered in the name of more than one owner (for example, joint ownership, trustees, executors, etc.), then all those registered should sign this VIF. If you are voting on behalf of a corporation or another individual you may be required to provide documentation evidencing your power to sign this VIF with signing capacity stated. 3. This VIF should be signed in the exact manner as the name(s) appear(s) on the VIF. 4. If a date is not inserted in the space provided on the reverse of this VIF, it will be deemed to bear the date on which it was mailed to the holder by Management. 5. The securities represented by this VIF will be voted as directed by the holder, however, if such a direction is not made in respect of any matter, and the VIF appoints the Management Nominees listed on the reverse, this VIF will be voted as recommended by Management. 6. The securities represented by this VIF will be voted in favour, or withheld from voting, or voted against each of the matters described herein, as applicable, in accordance with the instructions of the holder, on any ballot that may be called for. If you have specified a choice with respect to any matter to be acted on, the securities will be voted accordingly. 7. This VIF confers discretionary authority in respect of amendments or variations to matters identified in the Notice of Meeting and Management Information Circular or other matters that may properly come before the meeting or any adjournment or postponement thereof, unless prohibited by law. 8. This VIF should be read in conjunction with the accompanying documentation provided by Management. VIFs submitted must be received by 4:00 pm (Toronto time), on September 8, 2023. 8th Floor, 100 University Avenue Toronto, Ontario M5J 2Y1 www.computershare.com To Vote Using the Telephone • Call the number listed BELOW from a touch tone telephone. To Vote Using the Internet • Go to the following web site: www.investorvote.com • Smartphone? Scan the QR code to vote now. To Vote by Fax • Complete, sign and date the reverse hereof. • Forward it by fax to 1-866-249-7775 for calls within Canada and the U.S. There is NO CHARGE for this call. • Forward it by fax to 416-263-9524 for calls outside Canada and the U.S. Mr A Sample Designation (if any) Add1 Add2 add3 add4 add5 add6 C1234567890 XXX 000001 Plans CPUQC01.E.INT/000001/i1234 123456789012345 Holder Account Number Security Class 1-866-732-VOTE (8683) Toll Free

356765 01XMXB Fold Fold AR0 Signature of Proxyholder I/We authorize you to act in accordance with my/our instructions set out above. I/We hereby revoke any VIF previously given with respect to the meeting. If no voting instructions are indicated above, and the VIF appoints the Management Nominees, this VIF will be voted as recommended by Management. MM / DD / YY Signature(s) Date 1. Approval of Arrangement Resolution To consider and, if deemed advisable, to pass, with or without variation, pursuant to an interim order of the Supreme Court of British Columbia dated August 11, 2023, a special resolution (the “Arrangement Resolution”), the full text of which is set forth in “Schedule “C” – Arrangement Resolution” to the accompanying management information circular (the “Circular”), approving a plan of arrangement under Division 5 of Part 9 of the Business Corporations Act (British Columbia), involving, among others, the Corporation, Hut 8 Holdings Inc., its direct wholly-owned subsidiary existing under the laws of British Columbia, and Hut 8 Corp., a Delaware corporation (“New Hut”), in accordance with the terms of the business combination agreement dated February 6, 2023 by and among the Corporation, U.S. Data Mining Group, Inc., a Nevada corporation doing business as “US Bitcoin Corp” (“USBTC”), and New Hut (the “Business Combination Agreement”). For Against 2. Approval of New Hut Shares To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “D” – New Hut Resolution” to the accompanying Circular, to authorize the issuance of up to 49,665,834 shares of common stock of New Hut (the “New Hut Shares”), consisting of: (i) up to 44,161,669 New Hut Shares issuable to USBTC stockholders pursuant to the Business Combination Agreement and up to 4,530,326 New Hut Shares issuable upon the exercise of USBTC replacement options to be issued to USBTC stockholders in exchange for their USBTC options outstanding immediately prior to the Merger Effective Time (as defined under the Circular), which figures represent approximately 50% of the common stock of New Hut expected to be outstanding upon completion of the Business Combination (as defined under the Circular), and (ii) and up to 973,839 New Hut Shares, which represents an additional 2% buffer to account for clerical and administrative matters (the “New Hut Resolution”). For Against 3. Approval of the adoption of the New Hut incentive plan To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “E” – Incentive Plan Resolution” to the accompanying Circular, to approve the adoption of the New Hut incentive plan (the “Incentive Plan Resolution”, together with the Arrangement Resolution and New Hut Resolution, the “Hut 8 Resolutions”). For Against I/We being holder(s) of securities of Hut 8 Mining Corp. (the “Corporation”) hereby appoint: Jaime Leverton, or failing this person, Shenif Visram, or failing this person, Aniss Amdiss (the “Management Nominees”) Appointment of Proxyholder Print the name of the person you are appointing if this person is someone other than the Management Nominees listed herein. OR as my/our proxyholder with full power of substitution and to attend, act and to vote for and on behalf of the holder in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and on all other matters that may properly come before the Special Meeting of shareholders of the Corporation to be held at Bennett Jones LLP, 3400 One First Canadian Place, Toronto, ON M5X 1A4 on September 12, 2023 at 10:00 am (Toronto time), and at any adjournment or postponement thereof. VOTING RECOMMENDATIONS ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. C1234567890 XXX 123 MR SAM SAMPLE ORJQ XXXX 999999999999

The control number has been assigned to you to identify your shares for voting. You must keep your control number confidential and not disclose it to others other than when you vote using one of the voting options set out on this form. Should you send this form or provide your control number to others, you are responsible for any subsequent voting of, or subsequent inability to vote, your shares. Dear Client: A meeting is being held for securityholders of the above noted issuer. 1. You are receiving this Voting Instruction Form and the enclosed meeting materials at the direction of the issuer as a beneficial owner of securities. You are a beneficial owner because we, as your intermediary, hold the securities in an account for you and the securities are not registered in your name. 2. Votes are being solicited by or on behalf of the management of the issuer. 3. Even if you have declined to receive materials, a reporting issuer is entitled to deliver these materials to you and if requested to do so, it is our responsibility to forward them. These materials are being sent at no cost to you, in the language you requested, if available. 4. Unless you attend the meeting and vote in person or virtually (as applicable), your securities can only be voted through us as registered holder or proxyholder of the registered holder in accordance with your instructions. We cannot vote for you if we do not receive your voting instructions. Please provide your voting instructions to us promptly using one of the available voting methods or complete and return this form. We will submit a proxy vote on your behalf according to the voting instructions you provide, unless you elect to attend the meeting and vote in person or virtually (as applicable). 5. When you give us your voting instructions, you acknowledge that: • You are the beneficial owner or are authorized to provide these voting instructions; and • You have read the material and the voting instructions on this form. 6. You may not present this Voting Instruction Form at the meeting in order to vote. 7. To attend and vote your shares at the meeting: •Write your name or the name of your designate to act on your behalf on the “Appointee” line on the other side of this form, sign and date the form, and return it by mail, or •Go to ProxyVote.com (if available) and insert the name in the “Change Appointee(s)” section on the voting site. • For virtual meetings, you may need to complete additional information or take additional action for you or your Appointee to attend the meeting. Refer to the meeting material accompanying this voting instruction form for details. You, or your designate, as the named “Appointee”, must attend the meeting for your vote to be counted. 8. Unless prohibited by law or you instruct otherwise, the Appointee(s) or the person whose name is written in the space provided will have full authority to attend and otherwise act at, and present matters to the meeting and any adjournment or postponement thereof, and vote on all matters that are brought before the meeting or any adjournment or postponement thereof, even if these matters are not set out in this form or in the management proxy circular. Consult a legal advisor if you wish to modify the authority of that person in any way. If you require assistance, please contact the person who services your account. 9. If these voting instructions are given on behalf of a body corporate, set out the full legal name of the body corporate, the name and position of the person giving voting instructions on behalf of the body corporate and the address for service of the body corporate. 10. If the items listed in the management proxy circular are different from the items listed on the other side of this form, the management proxy circular will be considered correct. 11. The Appointee named in this form will exercise the voting rights attached to the securities in accordance with the instructions given. In the absence of any specific instructions as to voting being provided by you on this form, the item(s) will be voted as recommended on the reverse of this form or as stated in the management proxy circular, except in the case of your appointment of an Appointee. 12. This Voting Instruction Form should be read in conjunction with the accompanying management proxy circular. 13. To ensure that your instructions are received in sufficient time to be processed, please ensure that the Voting Instruction Form is received by us or voted online at least one business day before the proxy deposit date noted above or the proxy deadline specified in the management proxy circular. Voting instructions received on the proxy deposit date or later may not be able to be included in the final tabulation. This Voting Instruction Form confers discretionary authority to vote on such other business as may properly come before the meeting or any adjournment thereof. If you have any questions or require help, please contact the person who services your account. Disclosure of Information – Electing to Receive Financial Statements or Requesting Meeting Materials By electing to receive the financial statements or requesting meeting materials, your name and address may be provided to the reporting issuer (or its agent) for mailing purposes. PLEASE SEE OVER G-18062020 CONTROL NO.:➔ WE NEED TO RECEIVE YOUR VOTING INSTRUCTIONS AT LEAST ONE BUSINESS DAY BEFORE THE PROXY DEPOSIT DATE. SCAN TO VIEW MATERIAL AND VOTE NOW STEP 1 REVIEW YOUR VOTING OPTIONS BY TELEPHONE: YOU MAY ENTER YOUR VOTING INSTRUCTIONS BY TELEPHONE AT: ENGLISH: 1-800-474-7493 OR FRENCH: 1-800-474-7501 BY MAIL: THIS VOTING INSTRUCTION FORM MAY BE RETURNED BY MAIL IN THE ENVELOPE PROVIDED. REMINDER: PLEASE REVIEW THE INFORMATION / PROXY CIRCULAR BEFORE VOTING. ONLINE: VOTE AT PROXYVOTE.COM USING YOUR COMPUTER OR MOBILE DATA DEVICE. YOUR CONTROL NUMBER IS LOCATED BELOW. BROKER ADDRESS 123 ANY STREET ANY CITY/PROVINCE A1A 1A1 JOHN A. SAMPLE 123 ANY STREET ANYCITY PR A1A 1A1 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX BROKER LOGO 1 OF 2 S91970 81 010 E: C S:3 E:2 1/1 M A:A V: 1 PROXY DEPOSIT DATE: September 8, 2023 Tuesday, September 12, 2023 at 10:00 am EDT Bennett Jones LLP 3400 One First Canadian Place Toronto, ON M5X 1A4 Special Meeting Hut 8 Mining Corp. (the “Corporation”) WHEN: WHERE: VOTING INSTRUCTION FORM

IF YOU WISH TO ATTEND THE MEETING OR DESIGNATE ANOTHER PERSON TO ATTEND, VOTE AND ACT ON YOUR BEHALF AT THE MEETING, OR ANY ADJOURNMENT OR POSTPONEMENT THEREOF, OTHER THAN THE PERSON(S) SPECIFIED ABOVE, PRINT YOUR NAME OR THE NAME OF THE OTHER PERSON ATTENDING THE MEETING IN THE SPACE PROVIDED HEREIN. UNLESS YOU INSTRUCT OTHERWISE, THE PERSON WHOSE NAME IS WRITTEN IN THIS SPACE WILL HAVE FULL AUTHORITY TO ATTEND, VOTE AND OTHERWISE ACT IN RESPECT OF ALL MATTERS THAT MAY COME BEFORE THE MEETING OR ANY ADJOURNMENT OR POSTPONEMENT THEREOF, EVEN IF THESE MATTERS ARE NOT SET OUT IN THE FORM OR THE CIRCULAR. FOR VIRTUAL MEETINGS, YOU MAY NEED TO COMPLETE ADDITIONAL INFORMATION OR TAKE ADDITIONAL ACTION FOR YOU OR YOUR APPOINTEE TO ATTEND THE MEETING. CONTROL NO.: ➔ PLEASE PRINT APPOINTEE NAME ABOVE APPOINT A PROXY (OPTIONAL) STEP 4 THIS DOCUMENT MUST BE SIGNED AND DATED SIGNATURE(S) *INVALID IF NOT SIGNED* M M D D Y Y COMPLETE YOUR VOTING DIRECTIONS STEP 2 STEP 3 APPOINTEE(S): Jaime Leverton, or failing this person, Shenif Visram, or failing this person, Aniss Amdiss E-R3 VOTING INSTRUCTION FORM ACCOUNT NO: CUSIP: CUID: RECORD DATE: PROXY DEPOSIT DATE: August 8, 2023 September 8, 2023 MEETING DATE: Tuesday, September 12, 2023 at 10:00 am EDT MEETING TYPE: Special Meeting Hut 8 Mining Corp. (the “Corporation”) ITEM(S): HIGHLIGHTED TEXT 01 02 To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “E” – Incentive Plan Resolution” to the accompanying Circular, to approve the adoption of the New Hut incentive plan (the “Incentive Plan Resolution”, together with the Arrangement Resolution and New Hut Resolution, the “Hut 8 Resolutions”). 03 To consider and, if deemed advisable, to pass, with or without variation, pursuant to an interim order of the Supreme Court of British Columbia dated August 11, 2023, a special resolution (the “Arrangement Resolution”), the full text of which is set forth in “Schedule “C” – Arrangement Resolution” to the accompanying management information circular (the “Circular”), approving a plan of arrangement under Division 5 of Part 9 of the Business Corporations Act (British Columbia), involving, among others the Corporation, Hut 8 Holdings Inc., its direct wholly-owned subsidiary existing under the laws of British Columbia, and Hut 8 Corp., a Delaware corporation (“New Hut”), in accordance with the terms of the business combination agreement dated February 6, 2023 by and among the Corporation, U.S. Data Mining Group, Inc., a Nevada corporation doing business as “US Bitcoin Corp.” (“USBTC”), and New Hut (the “Business Combination Agreement”). To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “D” – New Hut Resolution” to the accompanying Circular, to authorize the issuance of up to 49,665,834 shares of common stock of New Hut (the “New Hut Shares”), consisting of: (i) up to 44,161,669 New Hut Shares issuable to USBTC stockholders pursuant to the Business Combination Agreement and up to 4,530,326 New Hut Shares issuable upon the exercise of USBTC replacement options to be issued to USBTC stockholders in exchange for their USBTC options outstanding immediately prior to the Merger Effective Time (as defined under the Circular), which figures represent approximately 50% of the common stock of New Hut expected to be outstanding upon completion of the Business Combination (as defined under the Circular), and (ii) and up to 973,839 New Hut Shares, which represents an additional 2% buffer to account for clerical and administrative matters (the “New Hut Resolution”). VOTING RECOMMENDATIONS ARE INDICATED BY OVER THE BOXES (FILL IN ONLY ONE BOX “ ” PER ITEM IN BLACK OR BLUE INK) FOR AGAINST FOR FOR AGAINST 34 AGAINST

VOIR AU VERSO Le numéro de contrôle vous a été attribué aux fins d’identification des actions à l’égard desquelles vous exercerez vos droits de vote. Vous devez préserver la confidentialité de votre numéro de contrôle et éviter de le divulguer à des tiers, sauf lorsque vous votez à l’aide de l’une des options de vote indiquées dans le présent formulaire. Si vous envoyez le présent formulaire ou fournissez votre numéro de contrôle à des tiers, vous êtes responsable de l’exercice subséquent des droits de vote rattachés à vos actions ou de l’incapacité subséquente de les exercer. Madame, Monsieur, Une assemblée sera tenue à l'intention des porteurs de titres de l'émetteur mentionné ci-dessus. 1. Vous recevez le présent formulaire d’instructions de vote et les documents relatifs à l’assemblée ci-joints, selon les directives de l’émetteur, en tant que propriétaire véritable des titres. Vous êtes le propriétaire véritable des titres parce qu’en tant qu’intermédiaires, nous détenons les titres dans un compte pour vous, mais ils ne sont pas immatriculés à votre nom. 2. Les votes sont sollicités par la direction de l’émetteur ou en son nom. 3. Même si vous ne souhaitez pas recevoir ces documents, l’émetteur assujetti a le droit de vous les faire parvenir et, si on nous le demande, il est de notre responsabilité de vous les envoyer. Ces documents vous sont envoyés sans frais, dans la langue de correspondance de votre choix, dans la mesure où ils sont disponibles dans cette langue. 4. À moins que vous n’assistiez à l’assemblée et que vous n’y votiez en personne ou virtuellement (selon le cas), nous sommes les seuls à pouvoir exercer les droits de vote rattachés à vos titres en notre qualité de porteurs inscrits ou de fondés de pouvoir du porteur inscrit conformément à vos instructions. Nous ne pouvons pas voter pour votre compte si nous ne recevons pas vos instructions de vote. Veuillez nous fournir vos instructions de vote dès que possible à l’aide de l’une ou l’autre des méthodes de vote disponibles ou remplir et nous retourner le présent formulaire. Nous soumettrons un vote par procuration en votre nom conformément aux instructions de vote que vous nous donnerez, à moins que vous ne choisissiez d’assister à l’assemblée et d’y voter en personne ou virtuellement (selon le cas). 5. En nous donnant vos instructions de vote, vous confirmez ce qui suit : • vous êtes le propriétaire véritable des titres ou vous êtes autorisé à donner ces instructions de vote; • vous avez lu les documents et les instructions de vote mentionnés dans le présent formulaire. 6. Vous ne pouvez pas présenter le présent formulaire d'instructions de vote lors de l’assemblée pour voter. 7. Pour assister à l’assemblée et y exercer les droits de vote rattachés à vos actions, veuillez procéder de l’une des manières suivantes : • écrivez votre nom ou le nom de la personne que vous avez désignée pour qu’elle agisse en votre nom sur la ligne « Fondé de pouvoir » au verso du présent formulaire que vous devez dater, signer et nous renvoyer par la poste; • allez au site ProxyVote.com (s’il est disponible) et inscrivez le nom dans la section « Changement de fondé de pouvoir » du site de vote; • en ce qui concerne les assemblées virtuelles, vous pourriez devoir fournir d’autres renseignements ou prendre d’autres mesures pour que vous ou votre fondé de pouvoir puissiez assister à l’assemblée. Pour de plus amples détails, veuillez vous reporter aux documents relatifs à l’assemblée qui accompagnent les présentes instructions de vote. Vous ou votre « fondé de pouvoir » devez assister à l’assemblée pour que votre vote soit comptabilisé. 8. Sauf si la loi l’interdit ou à moins d’instructions contraires de votre part, le ou les fondés de pouvoir ou la personne dont le nom est inscrit dans l’espace prévu à cet effet auront les pleins pouvoirs pour assister, soumettre des questions et agir à l’assemblée ou à toute reprise de celle-ci en cas d’ajournement ou de report, ainsi que pour voter à l’égard de toutes les questions qui y seront présentées, même si ces questions ne sont pas mentionnées dans le présent formulaire ou dans la circulaire de sollicitation de procurations. Consultez un conseiller juridique si vous souhaitez modifier les pouvoirs de cette personne de quelque façon que ce soit. Si vous avez besoin d’aide, veuillez communiquer avec le responsable de votre compte. 9. Si les présentes instructions de vote sont données au nom d’une société, indiquez la dénomination sociale complète de cette dernière, le nom et le titre de la personne donnant les instructions de vote au nom de la société, ainsi que l’adresse aux fins de signification de la société. 10. Si les points énoncés dans la circulaire de sollicitation de procurations sont différents des points mentionnés au verso du présent formulaire, la circulaire de sollicitation de procurations prévaudra. 11. Le fondé de pouvoir dont le nom figure dans le présent formulaire exercera les droits de vote rattachés aux titres en conformité avec les instructions données. En l’absence d’instructions de vote particulières de votre part dans le présent formulaire, les droits de vote seront exercés comme il est recommandé au verso du présent formulaire ou indiqué dans la circulaire de sollicitation de procurations, à moins que vous n’ayez nommé un fondé de pouvoir. 12. Le présent formulaire d’instructions de vote doit être lu conjointement avec la circulaire de sollicitation de procurations qui l’accompagne. 13. Afin que vos instructions soient reçues à temps pour être traitées, assurez-vous que le formulaire d’instructions de vote nous parvienne ou veuillez voter en ligne au moins un jour ouvrable avant la date de dépôt des procurations indiquée ci-dessus ou dans la circulaire de sollicitation de procurations. Les instructions de vote reçues à la date de dépôt des procurations ou par la suite pourraient ne pas être prises en compte dans la compilation finale. Le présent formulaire d’instructions de vote confère le pouvoir discrétionnaire de voter relativement aux autres questions qui peuvent être dûment soumises à l'assemblée ou à toute reprise de celle-ci. Si vous avez des questions ou avez besoin d’aide, veuillez communiquer avec le responsable de votre compte. Communication de l’information – Choix de recevoir les états financiers ou demande de documents relatifs à l’assemblée Si vous choisissez de recevoir les états financiers ou demandez les documents relatifs à l’assemblée, votre nom et votre adresse pourront être communiqués à l’émetteur assujetti (ou à son mandataire) aux fins d’envoi par la poste. H-18062020 NOUS DEVONS RECEVOIR VOS INSTRUCTIONS DE VOTE AU MOINS UN JOUR OUVRABLE AVANT LA DATE DE DÉPÔT DES PROCURATIONS. N DATE DE DÉPÔT : 8 septembre 2023 o DE CONTRÔLE : ➔ PASSEZ EN REVUE VOS OPTIONS DE VOTE NUMÉRISEZ POUR VOIR LES DOCUMENTS ET VOTEZ DÈS MAINTENANT ÉTAPE 1 ÉTAPE 3 VOTE PAR TÉLÉPHONE : VEUILLEZ TRANSMETTRE VOS INSTRUCTIONS AU 1 800 474-7501 (EN FRANÇAIS) OU 1 800 474-7493 (EN ANGLAIS). VOTE PAR LA POSTE : VEUILLEZ RETOURNER LE PRÉSENT FORMULAIRE D'INSTRUCTIONS DE VOTE DANS L’ENVELOPPE FOURNIE. RAPPEL : PASSEZ EN REVUE LA CIRCULAIRE DE SOLLICITATION DE PROCURATIONS AVANT DE VOTER. EN LIGNE : VOTEZ SUR PROXYVOTE.COM À L'AIDE DE VOTRE ORDINATEUR OU DE VOTRE APPAREIL PORTABLE. VOTRE NUMÉRO DE CONTRÔLE EST INDIQUÉ CI-DESSOUS. BROKER ADDRESS 123 ANY STREET ANY CITY/PROVINCE A1A 1A1 JOHN A. SAMPLE 123 ANY STREET ANYCITY PR A1A 1A1 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX BROKER LOGO 1 OF 2 S91970 81 010 E: C S:3 E:2 1/1 M A:A V: 1 DATE : ADRESSE : Mardi 12 septembre 2023 à 10 h HAE Bennett Jones LLP 3400 One First Canadian Place Toronto, ON M5X 1A4 Hut 8 Mining Corp. (the “Corporation”) Assemblée extraordinaire FORMULAIRE D’INSTRUCTIONS DE VOTE

SI VOUS VOULEZ ASSISTER À L’ASSEMBLÉE OU DÉSIGNER UNE AUTRE PERSONNE POUR QU’ELLE ASSISTE, VOTE ET AGISSE EN VOTRE NOM À L’ASSEMBLÉE OU À TOUTE ASSEMBLÉE RÉSULTANT D’UN AJOURNEMENT OU D’UN REPORT, AUTRE QUE LA OU LES PERSONNES MENTIONNÉES CI-DESSUS, INSCRIVEZ VOTRE NOM OU LE NOM DE L’AUTRE PERSONNE QUI ASSISTERA À L’ASSEMBLÉE DANS L’ESPACE PRÉVU À CET EFFET. À MOINS QUE VOUS NE DONNIEZ DES INSTRUCTIONS CONTRAIRES, LA PERSONNE DONT LE NOM EST ÉCRIT DANS CET ESPACE AURA LES PLEINS POUVOIRS POUR ASSISTER À L’ASSEMBLÉE, Y VOTER ET Y AGIR À L’ÉGARD DES QUESTIONS PRÉSENTÉES À L’ASSEMBLÉE OU À TOUTE ASSEMBLÉE RÉSULTANT D’UN AJOURNEMENT OU D’UN REPORT, MÊME SI CES QUESTIONS NE SONT PAS MENTIONNÉES DANS LE FORMULAIRE OU DANS LA CIRCULAIRE. EN CE QUI CONCERNE LES ASSEMBLÉES VIRTUELLES, VOUS POURRIEZ DEVOIR FOURNIR D’AUTRES RENSEIGNEMENTS OU PRENDRE D’AUTRES MESURES POUR QUE VOUS OU VOTRE FONDÉ DE POUVOIR PUISSIEZ Y ASSISTER. NOMMEZ UN FONDÉ DE POUVOIR (FACULTATIF) LE PRÉSENT DOCUMENT DOIT ÊTRE SIGNÉ ET DATÉ SIGNATURE(S) *INVALIDE EN L'ABSENCE DE SIGNATURE* MMJ J A A FONDÉ(S) DE POUVOIR : POINT(S) : TEXTE SURLIGNÉ INSTRUCTIONS DE VOTE ÉTAPE 4 ÉTAPE 3 ÉTAPE 2 ÉTAPE 3 ÉTAPE 3 ÉTAPE 3 INSCRIVEZ CI-DESSUS LE NOM DU FONDÉ DE POUVOIR EN LETTRES MAJUSCULES Jaime Leverton, ou à défaut, Shenif Visram, ou à défaut, Aniss Amdiss No DE CONTRÔLE : ➔ POUR CONTRE POUR CONTRE POUR CONTRE F-R3 FORMULAIRE D’INSTRUCTIONS DE VOTE N° DE COMPTE : DATE DE RÉFÉRENCE : DATE DE DÉPÔT : DATE DE L'ASSEMBLÉE : TYPE D'ASSEMBLÉE : 8 août 2023 8 septembre 2023 Mardi 12 septembre 2023 à 10 h HAE Assemblée extraordinaire Hut 8 Mining Corp. (the “Corporation”) N° CUSIP : N° CUID : LES RECOMMANDATIONS DE VOTE SONT INDIQUÉES AU MOYEN DU AU-DESSUS DES CASES (REMPLISSEZ UNE SEULE CASE « » PAR POINT, À L'ENCRE NOIRE OU BLEUE) 01 02 To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “E” – Incentive Plan Resolution” to the accompanying Circular, to approve the adoption of the New Hut incentive plan (the “Incentive Plan Resolution”, together with the Arrangement Resolution and New Hut Resolution, the “Hut 8 Resolutions”). 03 To consider and, if deemed advisable, to pass, with or without variation, pursuant to an interim order of the Supreme Court of British Columbia dated August 11, 2023, a special resolution (the “Arrangement Resolution”), the full text of which is set forth in “Schedule “C” – Arrangement Resolution” to the accompanying management information circular (the “Circular”), approving a plan of arrangement under Division 5 of Part 9 of the Business Corporations Act (British Columbia), involving, among others the Corporation, Hut 8 Holdings Inc., its direct wholly-owned subsidiary existing under the laws of British Columbia, and Hut 8 Corp., a Delaware corporation (“New Hut”), in accordance with the terms of the business combination agreement dated February 6, 2023 by and among the Corporation, U.S. Data Mining Group, Inc., a Nevada corporation doing business as “US Bitcoin Corp.” (“USBTC”), and New Hut (the “Business Combination Agreement”). To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “D” – New Hut Resolution” to the accompanying Circular, to authorize the issuance of up to 49,665,834 shares of common stock of New Hut (the “New Hut Shares”), consisting of: (i) up to 44,161,669 New Hut Shares issuable to USBTC stockholders pursuant to the Business Combination Agreement and up to 4,530,326 New Hut Shares issuable upon the exercise of USBTC replacement options to be issued to USBTC stockholders in exchange for their USBTC options outstanding immediately prior to the Merger Effective Time (as defined under the Circular), which figures represent approximately 50% of the common stock of New Hut expected to be outstanding upon completion of the Business Combination (as defined under the Circular), and (ii) and up to 973,839 New Hut Shares, which represents an additional 2% buffer to account for clerical and administrative matters (the “New Hut Resolution”). 34

WHEN: WHERE: VOTING INSTRUCTION FORM BROKER ADDRESS 123 ANY STREET ANY CITY/PROVINCE A1A 1A1 JOHN A. SAMPLE 123 ANY STREET ANYCITY PR A1A 1A1 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX BROKER LOGO 1 OF 2 S91970 81 010 E: C S:3 E:2 1/1 M A:A V: 1 PLEASE SEE OVER About Voting A meeting is being held for the holders of the securities listed on the other side of this form. As a beneficial holder of the securities you have the right to vote on the item(s) being covered at the meeting, which are described in the Proxy Statement. The control number has been assigned to you to identify your shares for voting. You must keep your control number confidential and not disclose it to others other than when you vote using one of the voting options set out on this form. Should you send this form or provide your control number to others, you are responsible for any subsequent voting of, or subsequent inability to vote, your shares. Please read the Proxy Statement carefully and take note of any relevant proxy deposit date. We need to receive your voting instructions at least one business day before the proxy deposit date noted on the reverse. If you have any questions, please contact the person who services your account. We have been requested to forward to you the enclosed proxy material relative to securities held by us in your account but not registered in your name. Only we as the holder of record can vote such securities. We shall be pleased to vote your securities in accordance with your wishes, if you will execute the form and return it to us promptly in the enclosed business reply envelope. It is understood that if you sign without otherwise marking the form your securities will be voted as recommended in the Proxy Statement. For this meeting, the extent of our authority to vote your securities in the absence of your instructions can be determined by referring to the applicable voting instruction number indicated on the face of your form. For margin accounts, in the event your securities have been loaned over record date, the number of securities we vote on your behalf has been or can be adjusted downward. Please note that under a rule amendment adopted by the New York Stock Exchange for shareholder meetings held on or after January 1, 2010, brokers are no longer allowed to vote securities held in their clients’ accounts on uncontested elections of directors unless the client has provided voting instructions (it will continue to be the case that brokers cannot vote their clients’ securities in contested director elections). Consequently, if you want us to vote your securities on your behalf on the election of directors, you must provide voting instructions to us. Voting on matters presented at shareholder meetings, particularly the election of directors is the primary method for shareholders to influence the direction taken by a publicly-traded company. We urge you to participate in the election by returning the enclosed voting instruction form to us with instructions as to how to vote your securities in this election. If your securities are held by a broker who is a member of the New York Stock Exchange (NYSE), the rules of the NYSE will guide the voting procedures. These rules provide that if instructions are not received from you prior to the issuance of the first vote, the proxy may be given at the discretion of your broker (on the tenth day, if the material was mailed at least 15 days prior to the meeting date or on the fifteenth day, if the proxy material was mailed 25 days or more prior to the meeting date). In order for your broker to exercise this discretionary authority, proxy material would need to have been mailed at least 15 days prior to the meeting date, and one or more of the matters before the meeting must be deemed “routine” in nature according to NYSE guidelines. If these two requirements are met and you have not communicated to us prior to the first vote being issued, we may vote your securities at our discretion on any matters deemed to be routine. We will nevertheless follow your instructions, even if our discretionary vote has already been given, provided your instructions are received prior to the meeting date. The following instructions provide specifics regarding the meeting for which this voting form applies. Instruction 1 All proposals for this meeting are considered “routine”. We may vote in our discretion on all proposals, if your instructions are not received. If your securities are held by a bank, your securities cannot be voted without your specific instructions. Instruction 2 In order for your securities to be represented at the meeting on one or more matters before the meeting, it will be necessary for us to have your specific voting instructions. If your securities are held by a bank, your securities cannot be voted without your specific instructions. Instruction 3 In order for your securities to be represented at the meeting, it will be necessary for us to have your specific voting instructions. Instruction 4 We have previously sent you proxy soliciting material pertaining to the meeting of shareholders of the company indicated. According to our latest records, we have not as of yet received your voting instruction on the matter(s) to be considered at this meeting and the company has requested us to communicate with you in an endeavor to have your securities voted. **If you hold your securities through a Canadian broker or bank, please be advised that you are receiving the voting instruction form and meeting materials, at the direction of the issuer. Even if you have declined to receive securityholder materials, a reporting issuer is required to deliver these materials to you. If you have advised your intermediary that you object to the disclosure of your beneficial ownership information to the reporting issuer, it is our responsibility to deliver these materials to you on behalf of the reporting issuer. These materials are being sent at no cost to you. To attend the meeting and vote your shares in person or virtually (as applicable) If you wish to attend the meeting, mark the appropriate box on the other side of this form, and a legal proxy will be issued and mailed to you. The legal proxy will grant you or your designate the right to attend the meeting and vote in person or virtually (as applicable), subject to any rules described in the Proxy Statement applicable to the delivery of a proxy. The legal proxy will be mailed to the name and address of the beneficial holder noted above. You need to submit and deliver the legal proxy in accordance with the proxy deposit date and any instructions or disclosures noted in the Proxy Statement. You or your designate must attend the meeting for your vote to be counted. Allow sufficient time for the mailing and return of the legal proxy by the proxy deposit date to the issuer or its agent. Please be advised that if you, the beneficial holder, ask for a legal proxy to be issued, you may have to take additional steps in order for the proxy to be fully effective under applicable law. For example, it may be necessary that you deposit the legal proxy with the issuer or its agent in advance of the meeting. Further, if a legal proxy is issued, all other voting instructions given on this voting instruction form will not be effective. This Voting Instruction Form confers discretionary authority to vote on such other business as may properly come before the meeting or any adjournment thereof. Disclosure of Information – Electing to Receive Financial Statements or Requesting Meeting Materials By electing to receive the financial statements or requesting meeting materials, your name and address may be provided to the issuer (or its agent) for mailing purposes. B-05022021 Tuesday, September 12, 2023 at 10:00 am EDT Bennett Jones LLP 3400 One First Canadian Place Toronto, ON M5X 1A4 Special Meeting Hut 8 Mining Corp. (the “Corporation”)

VOTING INSTRUCTION FORM A/C RECORD DATE: PROXY DEPOSIT DATE: MEETING DATE: MEETING TYPE: STEP 1 REVIEW YOUR VOTING OPTIONS BY TELEPHONE: YOU MAY ENTER YOUR VOTING INSTRUCTIONS BY TELEPHONE AT: BY MAIL: THIS VOTING INSTRUCTION FORM MAY BE RETURNED BY MAIL IN THE ENVELOPE PROVIDED. REMINDER: PLEASE REVIEW THE INFORMATION / PROXY CIRCULAR BEFORE VOTING. SEE VOTING INSTRUCTION NO. 2 ON REVERSE ONLINE: VOTE AT PROXYVOTE.COM USING YOUR COMPUTER OR MOBILE DATA DEVICE. ***WE NEED TO RECEIVE YOUR VOTING INSTRUCTIONS AT LEAST ONE BUSINESS DAY BEFORE THE PROXY DEPOSIT DATE.*** SCAN TO VIEW MATERIAL AND VOTE NOW ➔ STEP 2 COMPLETE YOUR VOTING DIRECTIONS ITEM(S): VOTING RECOMMENDATIONS ARE INDICATED BY OVER THE BOXES HIGHLIGHTED TEXT (FILL IN ONLY ONE BOX “ ” PER ITEM IN BLACK OR BLUE INK) FOR AGAINST FOR FOR AGAINST FILL IN THE BOX “ “ TO THE RIGHT IF YOU PLAN TO ATTEND THE MEETING AND VOTE THESE SHARES IN PERSON. STEP 3 THIS DOCUMENT MUST BE SIGNED AND DATED SIGNATURE(S) *INVALID IF NOT SIGNED* MMD D Y Y 0-R3 AGAINST August 8, 2023 September 8, 2023 Tuesday, September 12, 2023 at 10:00 am EDT Special Meeting Hut 8 Mining Corp. (the “Corporation”) 01 02 To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “E” – Incentive Plan Resolution” to the accompanying Circular, to approve the adoption of the New Hut incentive plan (the “Incentive Plan Resolution”, together with the Arrangement Resolution and New Hut Resolution, the “Hut 8 Resolutions”). 03 To consider and, if deemed advisable, to pass, with or without variation, pursuant to an interim order of the Supreme Court of British Columbia dated August 11, 2023, a special resolution (the “Arrangement Resolution”), the full text of which is set forth in “Schedule “C” – Arrangement Resolution” to the accompanying management information circular (the “Circular”), approving a plan of arrangement under Division 5 of Part 9 of the Business Corporations Act (British Columbia), involving, among others the Corporation, Hut 8 Holdings Inc., its direct wholly-owned subsidiary existing under the laws of British Columbia, and Hut 8 Corp., a Delaware corporation (“New Hut”), in accordance with the terms of the business combination agreement dated February 6, 2023 by and among the Corporation, U.S. Data Mining Group, Inc., a Nevada corporation doing business as “US Bitcoin Corp.” (“USBTC”), and New Hut (the “Business Combination Agreement”). To consider and, if deemed advisable, to pass, with or without variation, an ordinary resolution, the full text of which is set forth in “Schedule “D” – New Hut Resolution” to the accompanying Circular, to authorize the issuance of up to 49,665,834 shares of common stock of New Hut (the “New Hut Shares”), consisting of: (i) up to 44,161,669 New Hut Shares issuable to USBTC stockholders pursuant to the Business Combination Agreement and up to 4,530,326 New Hut Shares issuable upon the exercise of USBTC replacement options to be issued to USBTC stockholders in exchange for their USBTC options outstanding immediately prior to the Merger Effective Time (as defined under the Circular), which figures represent approximately 50% of the common stock of New Hut expected to be outstanding upon completion of the Business Combination (as defined under the Circular), and (ii) and up to 973,839 New Hut Shares, which represents an additional 2% buffer to account for clerical and administrative matters (the “New Hut Resolution”).