石桥收购 公司 如果您使用电子投票，请不要退还代理卡 。 23254石桥收购。公司代理卡Rev7正面 您的投票很重要。请今天投票。 立即-一天24小时、一周7天或通过邮寄投票 通过互联网投票-快速轻松 折叠此处不要单独插入信封PROVIDED INTERNET www.cstproxyvote.com Use投票您的代理。当您访问上述网站时，请确保您的 代理卡可用。按照提示投票 您的股票。 在会议上投票 如果您计划参加虚拟在线 特别股东大会，您需要 您的12位数字控制号码才能在临时股东大会上以电子方式投票 。要attend： https://www.cstproxy.com/ stonebridgespac/egm2023邮寄标记，请在您的代理卡上签名并注明日期，然后将其放在提供的已付邮资的信封中 退还。 亲自出席在德克萨斯州休斯敦国会街800号Suite2400， 温斯顿有限责任公司办公室举行的特别大会。 您的互联网投票授权指定的代理 以您 标记的相同方式投票您的股票，已签署并退回您的代理卡。 通过互联网以电子方式提交的投票必须在东部时间晚上11：59之前收到 [●]，2023年。 以下签署人任命 石桥收购公司首席执行官Bhargava Marepally(在业务合并前为“公司”，或业务合并后为“Stonebridge”，“pubco”)为代理人(“代理人”)，有权任命一名代理人在将举行的石桥股东特别大会上投票表决本人有权表决的股份(“股份”) []，2023年于[]:[]上午中部时间，亲自前往温斯顿与施特劳恩律师事务所位于美国得克萨斯州休斯敦2400号国会街800号Suit2400的办公室，或通过网络直播at https://www.cstproxy.com/stonebridgespac/egm2023或任何休会和/或延期。该等股份应按本文件背面所列建议进行表决，并由委托书就股东特别大会或其任何延会或延期的适当其他事项进行表决。 签署人确认已收到随附的委托书，并撤销本次特别大会之前的所有 委托书。 本委托书所代表的股份经适当签署及交付后，将按以下签署的 股东指示的方式投票表决。如果未对反面的提案给出具体指示，本委托书将表决通过提案1、2、3A、3B、3C、3D、3E、3F、 4、5和6。请立即在委托书上注明、签名、注明日期并退还。 (续并在背面注明日期和签名) 本委托书是代表石桥收购公司董事会征集的 纽约世贸中心一号楼8500室，邮编：纽约10007

石桥23254 Acq.公司代理卡版本7背面 关于股东特别大会代理材料供应的重要通知 将于[●], 2023 This notice of meeting and the accompanying proxy statement are available at https://www.cstproxy.com/stonebridgespac/egm2023 1. The Business Combination Proposal to consider and vote upon a proposal to approve the Business Combination Agreement, dated as of January 5, 2023 (as amended on June 22, 2023 by First Amendment to Business Combination Agreement, and as may be further amended, supplemented or otherwise modified from time to time, the “Business Combination Agreement”), by and among StoneBridge Acquisition Corporation, StoneBridge Acquisition Pte. Ltd., a Singapore private company limited by shares with company registration number 202239721R and a direct, wholly owned subsidiary of StoneBridge, DigiAsia Bios Pte. Ltd., a Singapore private company limited by shares with company registration number 201730295C and Prashant Gokarn (solely in his capacity as the Management Representative (as defined in the accompanying proxy statement)) and approve the business combination and the other transactions contemplated by the Business Combination Agreement and the terms thereto (the “Business Combination”). 2. The Amalgamation Proposal to consider and vote upon a proposal to approve, by ordinary resolution, the amalgamation between DigiAsia Bios Pte. Ltd. and StoneBridge Acquisition Pte. Ltd. (the “Amalgamation”) and certain matters relating to the Amalgamation. 3. The Governing Documents Proposal to consider and vote upon six separate proposals to approve, by special resolutions, material differences between StoneBridge’s current amended and restated memorandum and articles of association (the “Existing Charter”) and the second amended and restated memorandum and articles of association of PubCo (the “New Charter”) upon completion of the Business Combination, specifically: 3A to consider and vote for the effective change of PubCo’s corporate name from “StoneBridge Acquisition Corporation” to “DigiAsia Corp.” 3B to consider and vote for the effective change in authorized share capital from the authorized share capital of StoneBridge to the authorized share capital of PubCo. 3C to consider and vote for the effective change from the share structure of StoneBridge, comprising of Class A ordinary shares, par value $0.0001 per share (“StoneBridge Class A Ordinary Shares”), Class B ordinary shares, par value $0.0001 per share (“StoneBridge Class B Ordinary Shares,” and together with the StoneBridge Class A Ordinary Shares, the “StoneBridge Ordinary Shares”) and preference shares, par value $0.0001 per share, to a share structure of PubCo, comprising ordinary shares, par value $0.0001 per share (“PubCo Ordinary Shares”) and preference shares, par value $0.0001 per share. 3D to consider and vote for the effective change from the holders of StoneBridge Class B Ordinary Shares having the power to appoint or remove any director of StoneBridge by ordinary resolution under the terms of the Existing Charter, to the holders of PubCo Ordinary Shares having the power to appoint or remove the directors of PubCo by ordinary resolution under the terms of the New Charter. 3E to consider and vote for the effective change from the classified board of directors of StoneBridge, which is required to be divided into three classes, with directors serving staggered terms, to a declassified board of directors of PubCo, with each director serving until the next succeeding annual general meeting of PubCo after such director’s election and until their successors are appointed and qualified or until their earlier resignation or removal; and 3F to consider and vote for all other changes arising from or in connection with the replacement of the Existing Charter with the New Charter, including the removal of certain provisions relating to StoneBridge’s status as a blank check company that will not be applicable following consummation of the Business Combination. 4. The Nasdaq Proposal to consider and vote upon a proposal to approve, by ordinary resolution, for purposes of complying with Nasdaq Listing Rule 5635, the issuance of PubCo Ordinary Shares in connection with the Business Combination. 5. The Incentive Proposal to consider and vote upon a proposal to approve, by ordinary resolution, the DigiAsia Corp. 2023 Omnibus Incentive Plan. 6. The Adjournment Proposal to consider and approve, if presented, a proposal to adjourn the Extraordinary General Meeting to a later date or dates in the event that there are insufficient votes for, or otherwise in connection with, the approval of one or more proposals. CONTROL NUMBER Signature______________________________ Signature, if held jointly__________________________________ Date_____________, 2023 Note: Please sign exactly as name appears hereon. When shares are held by joint owners, both should sign. When signing as attorney, executor, administrator, trustee, guardian or corporate officer, please give full title as such. When signing as a corporation, please sign in full corporate name by president or other authorized officer. When signing as a partnership, please sign in partnership name by an authorized person. PROXY CARD STONEBRIDGE ACQUISITION CORPORATION - THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” PROPOSALS 1, 2, 3A, 3B, 3C, 3D, 3E, 3F, 4, 5 AND 6. Please mark your votes like this X FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN FOR AGAINST ABSTAIN