EX-10.4

**Exhibit 10.4 **

**AMENDED BUSINESS ALLIANCE AGREEMENT **

**BETWEEN **

**HOLTEC INTERNATIONAL, HOLTEC ASIA PRIVATE **

**LIMITED & MSl1 **

**Notice of Confidential and Proprietary Status **

**This document is confidential and proprietary to Holtec International and Holtec Asia. Unauthorized **

**dissemination to third parties is expressly forbidden. **

| | | | : | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | 1 | This document is subject to internal review and approval by both parties and must be entered in Holtec’s HI-COP app. at each stage of revision to be considered valid for use. This document will be updated as necessary to address the evolving business needs of HA and HI. |

1 | Page

This Alliance Agreement (“Agreement”) between Holtec International (HI), a Delaware corporation, and Holtec Asia Private Limited (HA), a private company organized under the laws of India, which was previously a subsidiary of HI, and Mariner Strategic Investments (MSI), is being established in recognition of HA being acquired by Holtec Holding Company, LLC (HHL) on December 31, 2025 at which time HA will transition to a sister company of HI. Accordingly, this Alliance Agreement between HI and HA is being executed to establish an arms-length relationship between the two parties which means all transactions will be conducted as if between unrelated parties. Under this arrangement, each party will be compensated for work completed by the other with utmost transparency and fairness. The Agreement contemplates a simplified billing mechanism by each party using a standardized invoicing process to ensure both parties’ compensation is fair and equitable.

HI is evaluating a potential public offering in 2026. HA intends to remain a privately held company for the foreseeable future and is owned by HHL which will also continue to own substantial equity in HI. The Nuclear Power Division (NPD) of HI is the principal business unit through which HI and HA each purchase goods and services from, and sell goods and services to, the other. Both HI and HA maintain three identically named business divisions, as set forth below, whose activities are complementary and, in some cases, overlapping:

As reflected above, HI and HA each purchase goods and services from, and sell goods and services to, the other. Accordingly, this Agreement establishes a costing and invoicing framework intended to ensure that such transactions are conducted on an arm’s-length basis and do not favor either party.

Accordingly, this Agreement establishes the framework under which HA and HI will conduct business transactions with one another. It sets forth the terms governing such transactions, including applicable fees and rates chargeable by each party to the other. The purpose of this Agreement is to provide for such transactions to be conducted on an arm’s length basis and to establish appropriate governance and transparency with respect to those transactions.

2 | Page

Both HI and HA may rely on MSI for Letters-of-Credit, performance bond, and other financial instruments, as necessary, to meet their evolving business needs.

MSI will charge the borrower the fee charged by the lending institution with n% adder where n is .75% for a facility under $30 million and would increase by .25% per $30 million per year in additional facility.

Both HI and HA have outstanding loans from HHL, which are due and payable to MSI (HHL’s Fund manager).

The MSI loan (s) will be interest free until April 1 2026 after which time the interest charged to both HI and HA will be equal to SOFR plus 1,5% where SOFR will correspond to the rate effective as of April 1 1 of each calendar year. The interest may be added to the principal annually until the borrower pays back to MSI.

3 | Page

HA shall pay HI the fees set forth below for goods, services, and support provided by HI to HA (collectively, the “HI Receivables”):

The monetary data for each receivable is listed in the table below:

Notwithstanding the foregoing, HA’s total aggregate financial obligation to **HI **under items (A), (B) and (C) above for any calendar year shall be capped at 8% of HA’s revenue for such calendar year.

4 | Page

For each engineering task assigned by HI to HA, a Not-to-Exceed (“NTE”) person-hour estimate shall be established prior to commencement of the work by an independent technical expert designated by HI. For Applied Mechanics assignments, the designated expert shall be Chuck Bullard. For Fluid Mechanics and Heat Transfer assignments, the designated expert shall be Abrar Mohammad. Additional technical experts may be designated by HI from time to time for other technical disciplines.

HA’s compensation for a task shall be determined by multiplying the approved NTE person hours by a fixed billing rate of Forty-Four Dollars and Forty Cents (US $44.40) per hour. Payment shall be based solely on the approved NTE hours and shall not be adjusted upward or downward based upon the actual hours expended or recorded by HA in performing the work.

If Debu Mitra-Majumdar, as HA’s representative, disagrees with an NTE determination made by the designated technical expert, he may formally challenge the determination. In such event, Dr. Kris Singh shall review the matter and act as a neutral mediator. Following such review, the NTE hours shall be confirmed or revised, and the resulting determination shall be final for purposes of compensation under this Agreement.

The parties acknowledge that this compensation methodology is intended to incentivize efficient execution of assigned work and to provide a transparent, objective basis for evaluating engineering productivity and cost performance.

The invoicing for engineering services provided by HI to HA shall be governed by the following provisions:

Both HI and HA will devote their resources to bid on heat exchange equipment, ACCs, HI-THERM HCSP, Green Boiler projects, including projects anticipated to be manufactured in India. If such a bid is successful and HA is the manufacturing entity, then HA will pay HI a fee that will not exceed 5% of the applicable selling price. HA will manufacture the equipment and carry the risk of profit and loss. If HI is the manufacturing entity, the foregoing allocation of fees, manufacturing responsibility, and profit and loss risk shall apply on a reciprocal basis.

5 | Page

The compensation schedules set forth in this Agreement are intended to apply to substantially all of the transactions between the HI and HA. In the event of a transaction not expressly addressed by this Agreement, the CFOs of HI and HA shall through mutual agreement determine an appropriate allocation of fees, profits, and losses consistent with the principles of this Agreement.

HI has the right to use another supplier for its engineering services and hardware needs if HA’s billing rate escalated beyond market price. Likewise, HA can elect to use another partner if Hi’s quality of service deteriorate or the cost is above the prevailing market rate in the United States.

HI’s CD-39 provides a comprehensive guidance on accounting and bookkeeping aspects of inter-company and intra-company transactions. This CD shall be used to the extent it is applicable to this Agreement.

HI’s GTC-07 will apply to all business transactions between HI and HA.

This Agreement will be governed by the laws of the State of New Jersey.

IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed by their respective authorized officers.

6 | Page

7 | Page