Supplement No. 1 to Collateral Agreement by NewPage Holdings Inc. and Wilmington Trust, National Association

Exhibit 10.6

EXECUTION VERSION

SUPPLEMENT NO. 1 dated as of January 7, 2015 (this “Supplement”), to the Collateral Agreement dated as of August 1, 2014 (the “Collateral Agreement”), among VERSO PAPER HOLDINGS LLC, a Delaware limited liability company (the “Company”), VERSO PAPER INC., a Delaware corporation (“Finance Co.” and, together with the Company, the “Issuers”), each Subsidiary of the Issuers identified on Schedule I or otherwise identified therein as a party (each, a “Subsidiary Party”) and WILMINGTON TRUST, NATIONAL ASSOCIATION, as Collateral Agent (in such capacity, the “Collateral Agent”) for the Secured Parties (as defined therein).

A. Reference is made to the Indenture dated as of August 1, 2014 (as amended, restated, supplemented or otherwise modified from time to time, the “Indenture”), among the Issuers, the Subsidiary Parties and Wilmington Trust, National Association, as Trustee (the “Trustee”).

B. Capitalized terms used herein and not otherwise defined herein shall have the meanings assigned to such terms in the Indenture and the Collateral Agreement referred to therein.

C. The Pledgors have entered into the Collateral Agreement in order to induce the Trustee to enter into the Indenture. Section 7.16 of the Collateral Agreement provides that additional Subsidiaries may become Subsidiary Parties under the Collateral Agreement by execution and delivery of an instrument in the form of this Supplement. The undersigned Subsidiary (the “New Subsidiary”) is executing this Supplement in accordance with the requirements of the Indenture to become a Subsidiary Party under the Collateral Agreement as consideration for credit previously extended to the Issuers.

Accordingly, the Collateral Agent and the New Subsidiary agree as follows:

SECTION 1. In accordance with Section 7.16 of the Collateral Agreement, the New Subsidiary by its signature below becomes a Subsidiary Party and a Pledgor under the Collateral Agreement with the same force and effect as if originally named therein as a Subsidiary Party and a Pledgor, and the New Subsidiary hereby (a) agrees to all the terms and provisions of the Collateral Agreement applicable to it as a Subsidiary Party and a Pledgor thereunder and (b) represents and warrants that the representations and warranties made by it as a Pledgor thereunder are true and correct, in all material respects, on and as of the date hereof. In furtherance of the foregoing, the New Subsidiary, as security for the payment and performance in full of the Obligations (as defined in the Collateral Agreement), does hereby create and grant to the Collateral Agent, for the ratable benefit of the Secured Parties, a security interest in and Lien on all the New Subsidiary’s right, title and interest in and to the Collateral (as defined in the Collateral Agreement) of the New Subsidiary. Each reference to a “Subsidiary Party” or a “Pledgor” in the Collateral Agreement shall be deemed to include the New Subsidiary. The Collateral Agreement is hereby incorporated herein by reference.

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SECTION 2. The New Subsidiary represents and warrants to the Collateral Agent and the other Secured Parties that this Supplement has been duly authorized, executed and delivered by it and constitutes its legal, valid and binding obligation, enforceable against it in accordance with its terms, subject to (i) the effects of bankruptcy, insolvency, moratorium, reorganization, fraudulent conveyance or other similar laws affecting creditors’ rights generally, (ii) general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law) and (iii) implied covenants of good faith and fair dealing.

SECTION 3. This Agreement may be executed in two or more counterparts, each of which shall constitute an original but all of which when taken together shall constitute but one contract. This Supplement shall become effective when (a) the Collateral Agent shall have received a counterpart of this Supplement that bears the signature of the New Subsidiary and (b) the Collateral Agent has executed a counterpart hereof.

SECTION 4. The New Subsidiary hereby represents and warrants that (a) set forth on Schedule I attached hereto is a true and correct schedule of all the Pledged Securities of the New Subsidiary as of the date hereof, (b) set forth on Schedule II attached hereto is a true and correct schedule of all of the material Patents, Trademarks and Copyrights of the New Subsidiary as of the date hereof, (c) set forth on Schedule III attached hereto is a true and correct schedule of all Commercial Tort Claims of the New Subsidiary individually in excess of $5.0 million as of the date hereof and (d) set forth under its signature hereto, is the true and correct legal name of the New Subsidiary, its jurisdiction of formation and the location of its chief executive office.

SECTION 5. Except as expressly supplemented hereby, the Collateral Agreement shall remain in full force and effect.

SECTION 6. THIS SUPPLEMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES UNDER THIS SUPPLEMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

SECTION 7. In the event any one or more of the provisions contained in this Supplement should be held invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein and in the Collateral Agreement shall not in any way be affected or impaired thereby. The parties shall endeavor in good-faith negotiations to replace the invalid, illegal or unenforceable provisions with valid provisions the economic effect of which comes as close as possible to that of the invalid, illegal or unenforceable provisions.

SECTION 8. All communications and notices hereunder shall be in writing and given as provided in Section 7.01 of the Collateral Agreement.

SECTION 9. The New Subsidiary agrees to reimburse the Collateral Agent for its reasonable out-of-pocket expenses in connection with this Supplement, including the reasonable fees, disbursements and other charges of counsel for the Collateral Agent.

EXECUTION VERSION

IN WITNESS WHEREOF, the New Subsidiary and the Collateral Agent have duly executed this Supplement to the Collateral Agreement as of the day and year first above written.

[Signature Page – Supplement to Guarantee and Collateral Agreement (New Second Lien Notes)]

Schedule I

to Supplement No. 1 to

the Collateral Agreement

Pledged Securities of the New Subsidiary

EQUITY INTERESTS

DEBT SECURITIES

Schedule II

to Supplement No. 1

to the Collateral Agreement

PATENTS, TRADEMARKS AND COPYRIGHTS

None.

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Schedule III

to Supplement No. 1

to the Collateral Agreement

COMMERCIAL TORT CLAIMS

None.

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