October 10, 2017

VIA ELECTRONIC TRANSMISSION

Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Re: Marathon Patent Group, Inc., Form S-3 Registration Statement

Ladies and Gentlemen:

We refer to the above-captioned registration statement on Form S-3 (the “Registration Statement”) under the Securities Act of 1933, as amended (the “Act”), filed by Marathon Patent Group, Inc., a Nevada corporation (the “Company”), with the Securities and Exchange Commission.

We have examined the originals, photocopies, certified copies or other evidence of such records of the Company, certificates of officers of the Company and public officials, and other documents as we have deemed relevant and necessary as a basis for the opinion hereinafter expressed. In such examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as certified copies or photocopies and the authenticity of the originals of such latter documents.

Based on our examination mentioned above, we are of the opinion that (i) the 6,596,000 shares of common stock of the Company (“Common Stock”) being sold pursuant to the Registration Statement, which shares are issuable upon conversion of certain 5% convertible promissory notes issued by the Company in August 2017 (the “Notes”) in a private placement of $3,623,700 of the Notes and five-year warrants to purchase shares of Common Stock, are duly authorized and will be, when issued in the manner described in the Registration Statement, legally and validly issued, fully paid and non-assessable and (ii) 798,000 shares of Common Stock which were issued in exchange for warrants to purchase 760,000 shares of Common Stock, pursuant to an exchange agreement dated July 16, 2017, by and between the Company and the purchaser of securities in the Company’s April 2017 offering, are duly authorized, legally and validly issued, fully paid and non-assessable.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement and to the reference to our firm under “Legal Matters” in the related Prospectus. In giving the foregoing consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Act, or the rules and regulations of the Securities and Exchange Commission.

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