Exhibit 5.1

787 Seventh Avenue New York, NY 10019-6099 Tel: 212 728 8000 Fax: 212 728 8111

November 12, 2026

RUM Group Inc.
444 Gulf of Mexico Dr.

Longboat Key, FL 34228

Re: Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to RUM Group Inc., a Delaware corporation (the “Company”), in connection with the automatic shelf registration statement on Form S-3 to be filed by the Company with the Securities and Exchange Commission (the “Commission”) on or about November 12, 2026 (the “Registration Statement”) relating to the registration under the Securities Act of 1933, as amended (the “Securities Act”), of the offering and sale from time to time of (i) shares of the Company’s Class A common stock, par value $0.0001 per share (the “Class A Common Stock”), (ii) shares of the Company’s preferred stock, $0.0001 par value per share (the “Preferred Stock”), (iii) depositary shares of the Company representing a fractional interest in a share of Preferred Stock (the “Depositary Shares”), (iv) one or more series of debt securities of the Company (the “Debt Securities”) issuable pursuant to an indenture (the “Indenture”) by and between the Company and a financial institution to be identified therein as trustee (the “Trustee”), (v) warrants to purchase Class A Common Stock, Preferred Stock, Depositary Shares and/or Debt Securities (the “Warrants”), (vi) subscription rights to purchase Class A Common Stock, Preferred Stock, Depositary Shares and/or Debt Securities (the “Subscription Rights”), and/or (vii) units consisting of any combination of such foregoing securities described in clauses (i) through (vi) above (the “Units”). The Class A Common Stock, the Preferred Stock, the Depositary Shares, the Debt Securities, the Warrants, the Subscription Rights and the Units are collectively referred to herein as the “Securities.” The Securities may be sold from time to time by the Company as set forth in the Registration Statement, the base prospectus contained within the Registration Statement (the “Prospectus”) and supplements to the Prospectus. The Company has informed us that it intends to issue the Securities from time to time on a delayed or continuous basis pursuant to Rule 415 under the Securities Act.

As to matters of fact relevant to the opinions rendered herein, we have examined such documents, certificates and other instruments which we have deemed necessary or advisable. We have not undertaken any independent investigation to verify the accuracy of any such information, representations or warranties or to determine the existence or absence of any fact, and no inference as to our knowledge of the existence or absence of any fact should be drawn from our representation of the Company or the rendering of the opinions set forth below. We have not considered parol evidence in connection with any of the agreements or instruments reviewed by us in connection with this letter.

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RUM Group Inc.
November 12, 2026
Page 2

In our examination of documents for purposes of this letter, we have assumed, and express no opinion as to, the genuineness and authenticity of all signatures on original documents, the authenticity and completeness of all documents submitted to us as originals, that each document is what it purports to be, the conformity to originals of all documents submitted to us as copies, the absence of any termination, modification or waiver of or amendment to any document reviewed by us (other than as has been disclosed to us), the legal competence or capacity of all persons or entities (other than the Company) executing the same and the due authorization, execution and delivery of all documents by each party thereto (other than the Company). We have also assumed the conformity of the documents filed with the Commission via the Electronic Data Gathering, Analysis and Retrieval System (“EDGAR”), except for required EDGAR formatting changes, to physical copies submitted for our examination.

The opinions in this letter are limited to the existing General Corporation Law of the State of Delaware now in effect and, as to the Debt Securities, the Warrants, the Subscription Rights and the Units constituting valid and binding obligations of the Company, the existing internal laws of the State of New York now in effect (collectively, the “Applicable Laws”), and we express no opinion with respect to any other laws.

In connection with our opinions expressed below, we have assumed that, (i) at or prior to the time of the delivery of any of the Securities, there will not have occurred any change in the law or the facts affecting the validity of the Securities, (ii) the Registration Statement and any amendments (including any necessary post-effective amendments) will become automatically effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, (iii) at the time of the offer, issuance and sale of any Securities, no stop order suspending the Registration Statement’s effectiveness will have been issued and remain in effect, (iv) no future amendments will be made to the Company’s current Second Amended and Restated Certificate of Incorporation (as amended from time to time, the “Certificate of Incorporation”) or to the Company’s Amended and Restated Bylaws (as amended from time to time, the “Bylaws” and, together with the Certificate of Incorporation, the “Charter Documents”) that would be in conflict with or inconsistent with the Company’s right and ability to issue the Securities, (v) at the time of the offer, issuance and sale of the Securities, the Company will be validly existing as a corporation and in good standing under the laws of the State of Delaware, and (vi) at the time of each offer, issuance and sale of any Securities, the Company will have a sufficient number of authorized and unissued and unreserved shares of the applicable class or series of its capital stock included in (or purchasable upon exercise or conversion of) the Securities so issued and sold (after taking into account all other outstanding securities of the Company which may require the Company to issue shares of such applicable class or series) to be able to issue all such shares.

The opinions herein are qualified by, and are subject to, and we render no opinion with respect to, the following limitations and exceptions to the enforceability of the Debt Securities, the Warrants, the Subscription Rights and the Units:

RUM Group Inc.
November 12, 2026
Page 3

We express no opinion regarding the effectiveness of any waiver or stay, extension or of unknown future rights. Further, we express no opinion regarding the effect of provisions relating to indemnification, exculpation or contribution to the extent such provisions may be held unenforceable as contrary to federal or state securities laws or public policy.

Based upon the foregoing, and subject to the qualifications and exceptions contained herein, we are of the following opinion:

1. With respect to the shares of Class A Common Stock registered pursuant to the Registration Statement, when (a) the issuance and the terms of the offering of such shares of Class A Common Stock and related matters have been duly authorized by all required corporate action of the Company’s Board of Directors (the “Board”) or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws and (b) if required, certificates representing the shares of Class A Common Stock have been duly executed, countersigned, registered and delivered in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board, or a duly authorized committee thereof, or upon the conversion or exercise of any Security offered under the Registration Statement, and when the consideration therefor (in an amount not less than the par value of the Class A Common Stock) has been paid, then such shares of Class A Common Stock will be validly issued, fully paid and nonassessable.

2. With respect to any particular series of shares of Preferred Stock registered pursuant to the Registration Statement, when (a) the issuance and terms of such series of shares of Preferred Stock, the terms of the offering thereof and related matters, including the adoption of one or more certificates of designations relating to such Preferred Stock (each, a “Certificate of Designations”) conforming to the Charter Documents and the Applicable Law, and the filing of the applicable Certificate of Designations with the Secretary of State of the State of Delaware (or the filing of an amendment to the Certificate of Incorporation to similar effect), have been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws and (b) if required, certificates representing the shares of Preferred Stock have been duly executed, countersigned, registered and delivered in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board or a duly authorized committee thereof, or upon conversion or exercise of any other Security offered under the Registration Statement, and when the consideration therefor (in an amount not less than the par value per share of such Preferred Stock) has been paid, then such shares of Preferred Stock will be validly issued, fully paid and nonassessable.

RUM Group Inc.
November 12, 2026
Page 4

3. With respect to any Depositary Shares registered pursuant to the Registration Statement, when (a) the issuance and the terms of such Depositary Shares, the term, execution and delivery of one or more deposit agreements relating to such Depositary Shares (each, a “Deposit Agreement”), the terms of the offering thereof and related matters have been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws, (b) the applicable Deposit Agreement has been validly executed and delivered by the Company and the depositary appointed by the Company, (c) validly issued, fully paid and non-assessable Preferred Stock represented by such Depositary Shares has been duly issued and delivered to the depositary under the applicable Deposit Agreement and (d) the receipts evidencing such Depositary Shares (each, a “Depositary Receipt”) have been duly executed and delivered by the Company, countersigned by the depositary and issued against the deposit of the underlying shares of Preferred Stock in accordance with the applicable Deposit Agreement approved by the Board or a duly authorized committee thereof, and when payment therefor has been paid, then such Depositary Shares will be validly issued and will entitle the holders thereof to the rights specified in such Depositary Receipts and in the applicable Deposit Agreement.

4. With respect to any Debt Securities registered pursuant to the Registration Statement, when (a) the issuance of such Debt Securities, the term, execution and delivery of one or more indentures relating to such Debt Securities in the form filed with the Registration Statement as an exhibit (each, an “Indenture”), the terms of the offering thereof and related matters has been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws, (b) the applicable Indenture has been duly authorized and validly executed and delivered by each of the Company and the Trustee, (c) the specific form and terms of the Debt Securities have been duly established in accordance with the applicable Indenture, duly authorized pursuant to resolutions duly adopted by the Board or a duly authorized committee thereof and validly executed, authenticated, issued, and delivered in accordance with the applicable Indenture and the applicable definitive purchase, underwriting or similar agreement, in the manner and for the consideration approved by the Board or a duly authorized committee thereof and stated in the prospectus supplement relating thereto (as amended as of the date of such issuance, sale and delivery), or upon the exercise of Warrants to purchase Debt Securities, and when the consideration therefor has been paid, then such Debt Securities will be validly issued and will constitute valid and binding obligations of the Company.

5. With respect to any Warrants registered pursuant to the Registration Statement, when (a) the issuance and terms of such Warrants, the terms, execution and delivery of one or more warrant agreements relating to the Warrants (each, a “Warrant Agreement”), the terms of the offering thereof and related matters have been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws, (b) the applicable Warrant Agreement has been duly authorized and validly executed and delivered by the Company, and (c) such Warrants have been duly executed, issued and delivered by the Company in accordance with the provisions of the applicable Warrant Agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board or a duly authorized committee thereof, and when the consideration therefor has been paid, then such Warrants will constitute valid and binding obligations of the Company.

RUM Group Inc.
November 12, 2026
Page 5

6. With respect to any Subscription Rights registered pursuant to the Registration Statement, when (a) the issuance and terms of such Subscription Rights, the terms, execution and delivery of one or more subscription rights agreements relating to the Subscription Rights (each, a “Subscription Rights Agreement”), the terms of the offering thereof and related matters have been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws, (b) the applicable Subscription Rights Agreement has been duly authorized and validly executed and delivered by the Company, and (c) such Subscription Rights have been duly executed, issued and delivered by the Company in accordance with the provisions of the applicable Subscription Rights Agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board or a duly authorized committee thereof, and when the consideration therefor has been paid, then such Subscription Rights will constitute valid and binding obligations of the Company.

7. With respect to any Units registered pursuant to the Registration Statement, when (a) the conditions outlined in the immediately preceding paragraphs (1) through (6) that apply to the Securities that make up such Units are all met, (b) the issuance and terms of such Units, the terms, execution and delivery of one or more unit purchase agreements relating to such Units (each, an “Unit Agreement”), the terms of the offering thereof and related matters have been duly authorized by all required corporate action of the Board or a duly authorized committee thereof and, if required, of the stockholders of the Company in accordance with the Charter Documents and the Applicable Laws, (c) the applicable Unit Agreement has been duly authorized and validly executed and delivered by the Company, and (d) such Units have been duly executed, issued and delivered by the Company in accordance with the provisions of the applicable Unit Agreement and the applicable definitive purchase, underwriting or similar agreement approved by the Board or a duly authorized committee thereof, and when the consideration therefor has been paid, then such Units will constitute valid and binding obligations of the Company.

In connection with the opinions expressed above, we have assumed that each of the Debt Securities and the applicable Deposit Agreement, the Indenture, Warrant Agreement, Subscription Rights Agreement and Unit Agreement governing such Securities constitutes legally valid and binding obligations of each party thereto other than the Company.

We consent to the use of this opinion letter as an exhibit to the Registration Statement and further consent to all references to us, if any, in the Registration Statement and the Prospectus constituting part thereof and any amendments thereto. In giving this consent, we do not thereby admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.

This opinion letter is intended solely for use in connection with the issuance and sale of the Securities subject to the Registration Statement and is not to be relied upon for any other purpose. In providing this letter, we are opining only as to the specific legal issues expressly set forth above, and no opinion shall be inferred as to any other matter or matters. This opinion letter is rendered on, and speaks only as of, the date of this letter first written above, is based solely on our understanding of facts in existence as of such date after the aforementioned examination and does not address any potential changes in facts, circumstance or law that may occur after the date of this opinion letter. We assume no obligation to advise you of any fact, circumstance, event or change in the law or the facts that may hereafter be brought to our attention, whether or not such occurrence would affect or modify any of the opinions expressed herein.