# EDGAR Filing Document

**Accession Number:** 0002021880
**File Stem:** 0000950157-26-000464
**Filing Date:** 2026-4
**Character Count:** 16278
**Document Hash:** 3e5f92a85bcea546543b26728202cc24
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000950157-26-000464.hdr.sgml**: 20260402

**ACCESSION NUMBER**: 0000950157-26-000464

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260402

**FILED AS OF DATE**: 20260402

**DATE AS OF CHANGE**: 20260402

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Mercury HoldCo AS
- **CENTRAL INDEX KEY:** 0002124920

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** Q8
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43221
- **FILM NUMBER:** 26833886

**BUSINESS ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** OKSENOYVEIEN 10
- **CITY:** LYSAKER
- **PROVINCE COUNTRY:** Q8
- **ZIP:** 1366
- **BUSINESS PHONE:** 47 67 51 30 00

**MAIL ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** OKSENOYVEIEN 10
- **CITY:** LYSAKER
- **PROVINCE COUNTRY:** Q8
- **ZIP:** 1366
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Akastor ASA
- **CENTRAL INDEX KEY:** 0002037057

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** Q8
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43221
- **FILM NUMBER:** 26833888

**BUSINESS ADDRESS:**
- **STREET 1:** OKSENOYVEIEN 10
- **CITY:** LYSAKER
- **STATE:** Q8
- **ZIP:** 1366
- **BUSINESS PHONE:** 47 67 51 30 00

**MAIL ADDRESS:**
- **STREET 1:** P.O. BOX 124
- **CITY:** LYSAKER
- **STATE:** Q8
- **ZIP:** 1325
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Mercury HoldCo Inc.
- **CENTRAL INDEX KEY:** 0002124922

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43221
- **FILM NUMBER:** 26833885

**BUSINESS ADDRESS:**
- **STREET 1:** 3300 NORTH SAM HOUSTON PARKWAY EAST
- **CITY:** HOUSTON
- **STATE:** TX
- **ZIP:** 77032
- **BUSINESS PHONE:** (281) 682-3087

**MAIL ADDRESS:**
- **STREET 1:** 3300 NORTH SAM HOUSTON PARKWAY EAST
- **CITY:** HOUSTON
- **STATE:** TX
- **ZIP:** 77032
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Akastor AS
- **CENTRAL INDEX KEY:** 0002124921

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** Q8
- **FISCAL YEAR END:** 1231
- **LEGAL ENTITY IDENTIFIER:** 549300DOU3BOW2TJRN20

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43221
- **FILM NUMBER:** 26833887

**BUSINESS ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** OKSENOYVEIEN 10
- **CITY:** LYSAKER
- **PROVINCE COUNTRY:** Q8
- **ZIP:** 1366
- **BUSINESS PHONE:** 47 67 51 30 00

**MAIL ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** OKSENOYVEIEN 10
- **CITY:** LYSAKER
- **PROVINCE COUNTRY:** Q8
- **ZIP:** 1366
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** HMH Holding Inc
- **CENTRAL INDEX KEY:** 0002021880
- **STANDARD INDUSTRIAL CLASSIFICATION:** OIL & GAS FILED MACHINERY & EQUIPMENT [3533]
- **ORGANIZATION NAME:** 01 Energy & Transportation
- **EIN:** 992746883
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 3300 NORTH SAM HOUSTON PARKWAY EAST
- **CITY:** HOUSTON
- **STATE:** TX
- **ZIP:** 77032
- **BUSINESS PHONE:** 281-449-2000

**MAIL ADDRESS:**
- **STREET 1:** 3300 NORTH SAM HOUSTON PARKWAY EAST
- **CITY:** HOUSTON
- **STATE:** TX
- **ZIP:** 77032

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Akastor ASA<br><sub>(Last) (First) (Middle)</sub><br>OKSENOYVEIEN 10<br><sub>(Street)</sub><br>LYSAKER, NORWAY 1366<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-04-02 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>HMH Holding Inc [ HMH ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Akastor AS<br><sub>(Last) (First) (Middle)</sub><br>OKSENOYVEIEN 10<br><sub>(Street)</sub><br>LYSAKER, NORWAY 1366<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-04-02 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [X] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_Director by Deputization_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>HMH Holding Inc [ HMH ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Mercury HoldCo AS<br><sub>(Last) (First) (Middle)</sub><br>OKSENOYVEIEN 10<br><sub>(Street)</sub><br>LYSAKER, NORWAY 1366<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-04-02 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>HMH Holding Inc [ HMH ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Mercury HoldCo Inc.<br><sub>(Last) (First) (Middle)</sub><br>3300 NORTH SAM HOUSTON PARKWAY EAST<br><sub>(Street)</sub><br>HOUSTON, TX 77032<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-04-02 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [X] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_Director by Deputization_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>HMH Holding Inc [ HMH ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Class B common stock | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  | 8144374 | A | $0 | 8144374 | I | Mercury HoldCo Inc. See footnotes<sup>(1)(2)(3)(4)(5)(6)</sup> |
| Class B common stock | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  | 8144374 | A | $0 | 16288748 | I | Akastor AS See footnotes<sup>(1)(2)(3)(4)(5)(6)</sup> |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| B.V. Voting Class A Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  |  | 1050000 | <sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 1050000 | $9.4 | 16288748 | I | Mercury HoldCo Inc.<sup>(1)(2)(3)(4)(5)(6)</sup> |
| B.V. Voting Class B Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  |  | 1050000 | <sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 1050000 | $9.4 | 16288748 | I | Akastor AS<sup>(1)(2)(3)(4)(5)(6)</sup> |
| B.V. Voting Class A Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  |  | 16288748 | <sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 16288748 | $0 | 0 | I | Mercury HoldCo Inc.<sup>(1)(2)(3)(4)(5)(6)</sup> |
| B.V. Voting Class B Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  |  | 16288748 | <sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 16288748 | $0 | 0 | I | Akastor AS<sup>(1)(2)(3)(4)(5)(6)</sup> |
| B.V. Non-Voting Class A Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  | 16288748 |  | 2026-09-27<sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 16288748 | $0 | 16288748 | I | Mercury HoldCo Inc.<sup>(1)(2)(3)(4)(5)(6)</sup> |
| B.V. Non-Voting Class B Shares | <sup>(1)(2)(3)(5)</sup> | 2026-04-02 |  | J<sup>(1)(2)(3)(5)</sup> |  | 16288748 |  | 2026-09-27<sup>(1)(2)(3)(5)</sup> | <sup>(1)(2)(3)(5)</sup> | Class A common stock | 16288748 | $0 | 16288748 | I | Akastor AS<sup>(1)(2)(3)(4)(5)(6)</sup> |

---

### Footnotes:

(1) Prior to the initial public offering ("IPO") of HMH Holding Inc. (the "Issuer"), (a) Akastor AS, a direct wholly owned subsidiary of Akastor ASA, held 50 Class B ordinary shares (the "B.V. Voting Class B Shares") of HMH Holding B.V. ("HMH B.V.") and (b) Mercury HoldCo Inc., an indirect wholly owned subsidiary of Akastor ASA (with Mercury HoldCo AS as an intermediary subsidiary between Akastor ASA and Mercury HoldCo Inc.) held 50 Class A ordinary shares (the "B.V. Voting Class A Shares") of HMH B.V. In this filing, Akastor ASA, Akastor AS, Mercury HoldCo AS and Mercury HoldCo Inc. are collectively referred to as "Akastor". (cont'd in fn 2)

(2) (cont'd from fn 1) In connection with the corporate reorganization and Akastor's participation in the synthetic secondary as described in the Issuer's Registration Statement on Form S-1 (Registration No. 333-281497), the following transactions have occurred: first, HMH B.V., the predecessor entity to the Issuer, underwent a 346,774.96 for 1 stock split, after which Akastor held 17,338,748 B.V. Voting Class B Shares (through Akastor AS) and 17,338,748 B.V. Voting Class A Shares (through Mercury HoldCo Inc.); second, HMH B.V. recapitalized to convert (i) 16,288,748 of Mercury HoldCo Inc.'s B.V. Voting Class A Shares to non-voting Class A ordinary shares (the "B.V. Non-Voting Class A Shares") and (ii) 16,288,748 of Akastor AS's B.V. Voting Class B Shares to non-voting Class B ordinary shares (the "B.V. Non-Voting Class B Shares"); (cont'd in fn 3)

(3) (cont'd from fn. 2) third, (i) Akastor AS sold 1,050,000 B.V. Voting Class B Shares, and Mercury HoldCo Inc. sold 1,050,000 B.V. Voting Class A Shares, in each case, to the Issuer in exchange cumulatively for $19,740,000 and (ii) each of Akastor AS and Mercury HoldCo Inc. received 8,144,374 shares of Class B common stock of the Issuer (the "Issuer Class B Shares") in exchange for relinquishing voting rights on their respective remaining 16,288,748 B.V. Voting Class B Shares (held by Akastor AS) and 16,288,748 B.V. Voting Class A Shares (held by Mercury HoldCo Inc.) that were recapitalized into 16,288,748 B.V. Non-Voting Class B Shares (held by Akastor AS) and 16,288,748 B.V. Non-Voting Class A Shares (held by Mercury HoldCo Inc.), respectively.

(4) Akastor ASA has an indirect pecuniary interest in the securities held by each of Akastor AS and Mercury HoldCo Inc. Mercury HoldCo AS has an indirect pecuniary interest in the securities held by Mercury HoldCo Inc.  Consequently, Akastor ASA may be deemed to share beneficial ownership in the securities held directly by Akastor AS, and Akastor ASA and Mercury HoldCo AS may be deemed to share beneficial ownership in the securities held directly by Mercury HoldCo Inc. The board of directors and officers of Akastor ASA, Mercury HoldCo Inc., Akastor AS and Mercury HoldCo AS disclaim beneficial ownership with respect to such securities.

(5) Pursuant to the Exchange Agreement, dated as of April 2, 2026, by and among the Issuer, HMH B.V. and the other parties thereto, Akastor has the right to exchange one Issuer Class B Share, one B.V. Non-Voting Class A Share and one B.V. Non-Voting Class B Share for cash or shares of the Issuer's Class A common stock on a one-for-one basis, subject to customary conversion rate adjustments (e.g. for stock splits, stock dividends and reclassifications). These rights are exercisable at any time after the conclusion of the Issuer's IPO lock-up period (i.e., September 27, 2026, unless the IPO lock-up is earlier released or waived by the underwriters of the Issuer's IPO) and do not expire.

(6) Karl Erik Kjelstad and Svein Oskar Stoknes are directors of the Issuer and were nominated for such roles by Akastor AS and Mercury HoldCo Inc. By virtue of their service on the Board of Directors of the Issuer, for purposes of Section 16, Akastor AS and Mercury HoldCo Inc. may be deemed to be a "director by deputization" of the Issuer.

**Signature:** /s/ Karl Erik Kjelstad, as Chief Executive Officer of Akastor ASA  
**Date:** 2026-04-02

**Signature:** /s/ Oyvind Paaske, Chair of Akastor AS  
**Date:** 2026-04-02

**Signature:** /s/ Oyvind Paaske, Chair of Mercury HoldCo AS  
**Date:** 2026-04-02

**Signature:** /s/ Askel Matre, Director of Mercury HoldCo Inc.  
**Date:** 2026-04-02

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**