Exhibit 5.1

August 14, 2017

New BKH Corp.

601 Riverside Avenue

Jacksonville, Florida 32204

(904) 854-5100

Ladies and Gentlemen:

We have acted as counsel to New BKH Corp., a Delaware corporation (the “Company”), in connection with the preparation and filing with the Securities and Exchange Commission (“The Commission”) of, and the consummation of the transactions contemplated by, the Company’s Registration Statement on Form S-1 (as it may be amended from time to time, the “Registration Statement”), filed by the Company with The Commission on the date hereof , under the Securities Act of 1933, as amended (the “Act”), relating to the registration and distribution by the Company of the number of shares of common stock, par value $0.0001 per share (the “common stock”), of the Company specified in the Registration Statement (the “Shares”). The Shares are to be distributed by the Company pursuant to a Reorganization Agreement by and among the Company, Fidelity National Financial, Inc., a Delaware corporation and Black Knight Holdings, Inc., a Delaware corporation (the “Agreement”), the form of which has been filed as Exhibit 2.2 to the Registration Statement.

In so acting, we have examined originals or copies (certified or otherwise identified to our satisfaction) of (i) the Certificate of Incorporation of the Company, which is filed as Exhibit 3.1 to the Registration Statement; (ii) the Amended and Restated Certificate of Incorporation of the Company, the form of which is filed as Exhibit 3.3 to the Registration Statement; (iii) the Bylaws of the Company, which are filed as Exhibit 3.2 to the Registration Statement; (iv) the Amended and Restated Bylaws of the Company, the form of which is filed as Exhibit 3.4 to the Registration Statement; (v) the Registration Statement; (vi) the prospectus contained within the Registration Statement; (vii) the Agreement; (vii) such corporate records, agreements, documents and other instruments, and such certificates or comparable documents of public officials and of officers and representatives of the Company, and have made such inquiries of such officers and representatives, as we have deemed relevant and necessary as a basis for the opinion hereinafter set forth.

In such examination, we have assumed the genuineness of all signatures, the legal capacity of all natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as certified, conformed or photostatic copies, and the authenticity of the originals of such latter documents. As to all questions of fact material to this opinion that have not been independently established, we have relied upon certificates or comparable documents of officers and representatives of the Company.

Based on the foregoing, and subject to the qualifications stated herein, we are of the opinion that the Shares, when distributed as contemplated by the Registration Statement and the Agreement, and upon

payment and delivery in accordance with the Agreement, will be validly issued, fully paid and non-assessable.

The opinions expressed herein are limited to the corporate laws of the State of Delaware and we express no opinion as to the effect on the matters covered by this letter of the laws of any other jurisdiction.

We hereby consent to the filing of this letter as an exhibit to the Registration Statement and to the reference to our firm under the caption “Legal Matters” in the prospectus which is a part of the Registration Statement. In giving such 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.

Very truly yours,