# EDGAR Filing Document

**Accession Number:** 0002069856
**File Stem:** 0001213900-25-068934
**Filing Date:** 2025-7
**Character Count:** 41391
**Document Hash:** d3b6be2c4108a23c0e15351a49f326e4
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-25-068934.hdr.sgml**: 20250730

**ACCESSION NUMBER**: 0001213900-25-068934

**CONFORMED SUBMISSION TYPE**: S-1/A

**PUBLIC DOCUMENT COUNT**: 4

**FILED AS OF DATE**: 20250730

**DATE AS OF CHANGE**: 20250730

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** HCM III ACQUISITION CORP.
- **CENTRAL INDEX KEY:** 0002069856
- **STANDARD INDUSTRIAL CLASSIFICATION:** BLANK CHECKS [6770]
- **ORGANIZATION NAME:** 05 Real Estate & Construction
- **EIN:** 981854444
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-1/A
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-287841
- **FILM NUMBER:** 251163869

**BUSINESS ADDRESS:**
- **STREET 1:** 100 FIRST STAMFORD PLACE, #330
- **CITY:** STAMFORD
- **STATE:** CT
- **ZIP:** 03902
- **BUSINESS PHONE:** 203-930-2200

**MAIL ADDRESS:**
- **STREET 1:** 100 FIRST STAMFORD PLACE, #330
- **CITY:** STAMFORD
- **STATE:** CT
- **ZIP:** 03902

#### As filed with the Securities and Exchange Commission on July 30 , 2025

#### Registration No. 333-287841

#### UNITED STATES<br>SECURITIES AND EXCHANGE COMMISSION<br>Washington, D.C. 20549
**_________________________**

#### AMENDMENT NO. 3 <br>TO<br>FORM S-1<br>REGISTRATION STATEMENT<br>UNDER<br>THE SECURITIES ACT OF 1933
**_________________________**

#### HCM III Acquisition Corp.<br> (Exact name of registrant as specified in its charter)
**_________________________**

---

| | | |
|:---|:---|:---|
|  **Cayman Islands** | **6770** | **98-1854444** |
|  (State or other jurisdiction of <br>incorporation or organization) | (Primary Standard Industrial <br>Classification Code Number) | (I.R.S. Employer <br>Identification Number) |

---

**Shawn Matthews<br>Chairman and Chief Executive Officer<br>100 First Stamford Place, Suite 330<br>Stamford, CT 06902<br>(203) 930-2200<br>(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)**

**_________________________**

**Shawn Matthews<br>Chairman and Chief Executive Officer<br>100 First Stamford Place, Suite 330<br>Stamford, CT 06902<br>(203) 930-2200<br>(Name, address, including zip code, and telephone number, including area code, of agent for service)**

**_________________________**

*Copies to:*

---

| | |
|:---|:---|
|  **Kevin E. Manz <br>King & Spalding LLP <br>1185 Avenue of the Americas, 34**<sup>th</sup> **Floor <br>New York, New York 10036 <br>(212) 556, 2100** | **Douglas S. Ellenoff <br>Stuart Neuhauser <br>Ellenoff Grossman & Schole LLP <br>1345 Avenue of the Americas, 11**<sup>th</sup> **Floor <br>New York, New York 10105 <br>(212) 370**-1300 |

---

**_________________________**

**Approximate date of commencement of proposed sale to the public:** As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box. ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

<u> Large accelerated filer </u>   <u> ☐ </u>   <u> Accelerated filer </u>   <u> ☐ </u> <br> <u> Non-accelerated filer </u>   <u> ☒ </u>   <u> Smaller reporting company </u>   <u> ☒ </u> <br>         <u> Emerging growth company </u>   <u> ☒ </u>

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

**The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.**

------

#### EXPLANATORY NOTE
HCM III Acquisition Corp is filing this Amendment No. 3 (this "Amendment") to its Registration Statement on Form S-1 (File No. 333-287841) (the "Registration Statement") as an exhibit-only filing to file Exhibit 5.2. Accordingly, this Amendment consists only of the facing page, this explanatory note, Part II of the Registration Statement, the signature page to the Registration Statement and the filed exhibit. The remainder of the Registration Statement is unchanged and has been omitted.

------

#### Part II

#### Information not required in prospectus
**Item 13. *Other Expenses of Issuance and Distribution.***

The estimated expenses payable by us in connection with the offering described in this registration statement (other than the underwriting discount and commissions) will be as follows:

---

| | |
|:---|:---|
|  Legal fees and expenses | 300000 |
|  Printing and engraving expenses | 40000 |
|  Trustee fees and expenses | 40000 |
|  Accounting fees and expenses | 50000 |
|  SEC/FINRA expenses | 61120 |
|  Travel and road show expenses | 7000 |
|  Nasdaq listing fees | 85000 |
|  Miscellaneous | 166880 |
|  **Total** | $**750000** |

---

**Item 14. *Indemnification of Directors and Officers.***

Cayman Islands law does not limit the extent to which a company's memorandum and articles of association may provide for indemnification of officers and directors, except to the extent any such provision may be held by the Cayman Islands courts to be contrary to public policy, such as to provide indemnification against willful default, willful neglect, actual fraud or the consequences of committing a crime. Our amended and restated memorandum and articles of association will provide for indemnification of our officers and directors to the maximum extent permitted by law, including for any liability incurred in their capacities as such, except through their own actual fraud, willful default or willful neglect. We will enter into agreements with our directors and officers to provide contractual indemnification in addition to the indemnification provided for in our amended and restated memorandum and articles of association. We expect to purchase a policy of directors' and officers' liability insurance that insures our officers and directors against the cost of defense, settlement or payment of a judgment in some circumstances and insures us against our obligations to indemnify our officers and directors.

Our officers and directors have agreed to waive any right, title, interest or claim of any kind in or to any monies in the trust account, and have agreed to waive any right, title, interest or claim of any kind they may have in the future as a result of, or arising out of, any services provided to us and will not seek recourse against the trust account for any reason whatsoever (except to the extent they are entitled to funds from the trust account due to their ownership of public shares). Accordingly, any indemnification provided will only be able to be satisfied by us if (i) we have sufficient funds outside of the trust account or (ii) we consummate an initial business combination.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or persons controlling us pursuant to the foregoing provisions, we have been informed that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

**Item 15. *Recent Sales of Unregistered Securities.***

On April 16, 2025, our sponsor paid $25,000, or approximately $0.004 per share, to cover certain of our offering costs in exchange for 7,666,667 founder shares. On May 29, 2025, the Company through a share recapitalization issued an additional 766,666 Class B ordinary shares to the Sponsor and therefore the Sponsor now holds 8,433,333 founder shares, at approximately, $0.003 per share. Such securities were issued in connection with our organization pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act. The number of founder shares outstanding was determined based on the expectation that the total size of this offering would be a maximum of 25,300,000 units if the underwriters' over-allotment option is exercised in full and therefore that such founder shares would represent 25% of the outstanding shares after this offering. Up to 1,100,000 of these shares will be surrendered for no consideration depending on the extent to which the underwriters' over-allotment option is exercised.

Our sponsor is an accredited investor for purposes of Rule 501 of Regulation D. Each of the equity holders in our sponsor is an accredited investor under Rule 501 of Regulation D. The sole business of our sponsor is to act as the company's sponsor in connection with this offering. The limited liability company agreement of our sponsor provides that its membership interests may only be transferred to our officers or directors or other persons affiliated with our sponsor, or in connection with estate planning transfers.

Our sponsor and Cantor Fitzgerald & Co., the representative of the underwriters, have committed to, pursuant to written agreements, purchase an aggregate of 4,266,667 warrants (whether or not the underwriters' over-allotment option is exercised in full), each exercisable to purchase one Class A ordinary share at $11.50 per share, at a price of $1.50 per warrant, or $6,400,000 in the aggregate, in a private placement that will close simultaneously with the closing of this offering. Of those 4,266,667 Private Placement Warrants, the Sponsor has agreed to purchase 3,533,333 Private Placement Warrants and Cantor Fitzgerald & Co. has agreed to purchase 733,334 Private Placement Warrants. The private placement warrants will also be worthless if we do not complete our initial business combination. This purchase will take place on a private placement basis simultaneously with the completion of our initial public offering. This issuance will be made pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act.

No underwriting discounts or commissions were paid with respect to such sales.

**Item 16. *Exhibits and Financial Statement Schedules.***

#### Exhibit Index

---

| | |
|:---|:---|
|  **Exhibit No.** | **Description** |
|  1.1\* | [Form of Underwriting Agreement.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex1-1_hcmacq3.htm) |
|  3.1\* | [Memorandum and Articles of Association.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex3-1_hcmacq3.htm) |
|  3.2\* | [Form of Amended and Restated Memorandum and Articles of Association.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex3-2_hcmacq3.htm) |
|  4.1\* | [Specimen Unit Certificate.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex4-1_hcmacq3.htm) |
|  4.2\* | [Specimen Ordinary Share Certificate.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex4-2_hcmacq3.htm) |
|  4.3\* | [Specimen Warrant Certificate.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex4-3_hcmacq3.htm) |
|  4.4\* | [Form of Warrant Agreement between Continental Stock Transfer & Trust Company and the Registrant.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex4-4_hcmacq3.htm) |
|  5.1\* | [Opinion of King & Spalding LLP.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025066991/ea024160805ex5-1_hcmacq3.htm) |
|  5.2† | [<u>Opinion of Maples and Calder (Cayman) LLP, Cayman Islands counsel to the Registrant.</u>](ea024160807ex5-2_hcm3.htm) |
|  10.1\* | [Form of Letter Agreement among the Registrant, HCM Investor Holdings III, LLC and each of the officers and directors of the Registrant.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-1_hcmacq3.htm) |
|  10.2\* | [Form of Investment Management Trust Agreement between Continental Stock Transfer & Trust Company and the Registrant.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-2_hcmacq3.htm) |
|  10.3\* | [Form of Registration Rights Agreement among the Registrant, HCM Investor Holdings III, LLC and the Holders signatory thereto.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-3_hcmacq3.htm) |
|  10.4\* | [Form of Private Placement Warrants Purchase Agreement between the Registrant and HCM Investor Holdings III, LLC.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-4_hcmacq3.htm) |
|  10.5\* | [Form of Private Placement Warrants Purchase Agreement between the Registrant and Cantor Fitzgerald & Co.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-5_hcmacq3.htm) |
|  10.6\* | [Form of Indemnity Agreement.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-6_hcmacq3.htm) |
|  10.7\* | [Promissory Note issued to HCM Investor Holdings III, LLC.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-7_hcmacq3.htm) |
|  10.8\* | [Securities Subscription Agreement between HCM Investor Holdings III, LLC and the Registrant.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-8_hcmacq3.htm) |
|  10.9\* | [Form of Administrative Services Agreement.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex10-9_hcmacq3.htm) |
|  14.1\* | [Form of Code of Ethics.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex14-1_hcmacq3.htm) |
|  23.1\* | [Consent of Withum Smith+Brown, PC.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025066991/ea024160805ex23-1_hcmacq3.htm) |
|  23.2\* | [Consent of King & Spalding LLP (included on Exhibit 5.1).](http://www.sec.gov/Archives/edgar/data/2069856/000121390025066991/ea024160805ex5-1_hcmacq3.htm) |
|  23.3† | [<u>Consent of Maples and Calder (Cayman) LLP (included on Exhibit 5.2).</u>](ea024160807ex5-2_hcm3.htm) |
| 24.1 | [Power of Attorney (included on the signature page of the initial filing).](#T500) |
|  99.1\* | [Audit Committee Charter.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex99-1_hcmacq3.htm) |

---

---

| | |
|:---|:---|
|  **Exhibit No.** | **Description** |
|  99.2\* | [Compensation Committee Charter.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex99-2_hcmacq3.htm) |
|  99.3\* | [Consent of Richard Donohoe to be named as director nominee.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex99-3_hcmacq3.htm) |
|  99.4\* | [Consent of Craig Goos to be named as director nominee.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex99-4_hcmacq3.htm) |
|  99.5\* | [Consent of Jacob Loveless to be named as director nominee.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025063336/ea024160803ex99-5_hcmacq3.htm) |
|  107\* | [Filing Fee Table.](http://www.sec.gov/Archives/edgar/data/2069856/000121390025052085/ea024160801ex-fee_hcm3.htm) |

---

____________

\* Filed previously.

† Filed herewith

**Item 17. *Undertakings.***

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) The undersigned registrant hereby undertakes to provide to the underwriters at the closing specified in the underwriting agreement, certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c) The undersigned registrant hereby undertakes that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1) For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) For the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial *bona fide* offering thereof.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3) For the purpose of determining liability under the Securities Act of 1933 of any purchaser, if the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(4) For the purpose of determining liability of a registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of an undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by an undersigned registrant;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) the portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv) any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

#### Signatures
Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in New York, New York, on the 30<sup>th</sup> day of July, 2025.

---

| | |
|:---|:---|
|  **HCM III Acquisition Corp.** | **HCM III Acquisition Corp.** |
|  By: | /s/ Shawn Matthews |
|  Name: | Shawn Matthews |
|  Title: | Chief Executive Officer |

---

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
|  **Name** | **Position** | **Date** |
|  /s/ Shawn Matthews | Chief Executive Officer and Director | July 30, 2025 |
|  Shawn Matthews | (principal executive officer) |  |
|  /s/ Steven Bischoff | Chief Financial Officer | July 30, 2025 |
|  Steven Bischoff | (principal financial and accounting officer) |  |

---

#### Authorized representative IN THE UNITED STATES
Pursuant to the requirements of Section 6(a) of the Securities Act of 1933, the undersigned has signed this registration statement, solely in its capacity as the duly authorized representative of HCM III Acquisition Corp., in New York, New York, on the 30<sup>th</sup> day of July, 2025.

---

| | |
|:---|:---|
|  By: | /s/ Shawn Matthews |
|  Name: | Shawn Matthews |
|  Title: | Chief Executive Officer |

---

## Exhibit 5.2

**Exhibit 5.2**

![](ex5-2_001.jpg)

Our ref ZAX/836253-000001/83130496v5

HCM III Acquisition Corp.

PO Box 309, Ugland House

Grand Cayman

KY1-1104

Cayman Islands

30 July 2025

**HCM III Acquisition Corp.**

We have acted as counsel as to Cayman Islands law to HCM III Acquisition Corp. (the "**Company**") in connection with the Company's registration statement on Form S-1, including all amendments or supplements thereto, filed with the United States Securities and Exchange Commission (the "**Commission**") under the United States Securities Act of 1933, as amended (the "**Act**") (including its exhibits, the "**Registration Statement**") for the purposes of, registering with the Commission under the Act, the offering and sale to the public of:

(a) up to 25,300,000 units (including 3,300,000 units, which the several underwriters ()"**Underwriters** "),
for whom Cantor Fitzgerald & Co. is acting as representative ()"**Representative** "), will have a 45-day option to purchase
from the Company to cover over-allotments, if any) ()"**Units**") at an offering price of US$10 per Unit, each Unit consisting
of:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1) one Class A ordinary share of a par value of US$0.0001 of the Company ()"**Class A Ordinary Shares** ");
and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) one-third of one redeemable warrant, each whole warrant exercisable to purchase one Class A Ordinary Share
at a price of US$11.50 per Class A Ordinary Share ()"**Warrants** "); and

(b) all Class A Ordinary Shares and Warrants issued as part of the Units; and

(c) all Class A Ordinary Shares that may be issued upon exercise of the Warrants included in the Units.

This opinion letter is given in accordance with the terms of the Legal Matters section of the Registration Statement.

1 Documents Reviewed

We have reviewed originals, copies, drafts or conformed copies of the following documents:

1.1 The certificate of incorporation dated 15 April 2025 and the memorandum and articles of association of
the Company as registered or adopted on 15 April 2025 (the "**Memorandum and Articles** ").

![](ex5-2_002.jpg)

1.2 The written resolutions of the board of directors of the Company dated 29 May 2025 and 15 April 2025 (the
" **Resolutions** ").

1.3 A certificate of good standing with respect to the Company issued by the Registrar of Companies (the "**Certificate of Good Standing** ").

1.4 A certificate from a director of the Company a copy of which is attached to this opinion letter (the "**Director's Certificate** ").

1.5 The Registration Statement.

1.6 A draft of the form of the unit certificate representing the Units (the "**Unit Certificate** ").

1.7 A draft of the form of the warrant agreement and the warrant certificate constituting the Warrants (the
" **Warrant Documents** ").

1.8 A draft of the underwriting agreement between the Company and the Representative.

The documents listed in paragraphs 1.6 to 1.8 inclusive above shall be referred to collectively herein as the "**Documents**".

2 Assumptions

The following opinions are given only as to, and based on, circumstances and matters of fact existing and known to us on the date of this opinion letter. These opinions only relate to the laws of the Cayman Islands which are in force on the date of this opinion letter. In giving the following opinions, we have relied (without further verification) upon the completeness and accuracy, as at the date of this opinion letter, of the Director's Certificate and the Certificate of Good Standing. We have also relied upon the following assumptions, which we have not independently verified:

2.1 The Documents have been or will be authorised and duly executed and unconditionally delivered by or on
behalf of all relevant parties in accordance with all relevant laws (other than, with respect to the Company, the laws of the Cayman Islands).

2.2 The Documents are, or will be, legal, valid, binding and enforceable against all relevant parties in accordance
with their terms under the laws of the State of New York (the "**Relevant Law**") and all other relevant laws (other than,
with respect to the Company, the laws of the Cayman Islands).

2.3 The choice of the Relevant Law as the governing law of the Documents has been made in good faith and would
be regarded as a valid and binding selection which will be upheld by the courts of the State of New York and any other relevant jurisdiction
(other than the Cayman Islands) as a matter of the Relevant Law and all other relevant laws (other than the laws of the Cayman Islands).

2.4 Copies of documents, conformed copies or drafts of documents provided to us are true and complete copies
of, or in the final forms of, the originals.

2.5 All signatures, initials and seals are genuine.

2.6 The capacity, power, authority and legal right of all parties under all relevant laws and regulations
(other than, with respect to the Company, the laws and regulations of the Cayman Islands) to enter into, execute, unconditionally deliver
and perform their respective obligations under the Documents.

2.7 No invitation has been or will be made by or on behalf of the Company to the public in the Cayman Islands
to subscribe for any of the Units, the Warrants or the Class A Ordinary Shares.

2.8 There is no contractual or other prohibition or restriction (other than as arising under Cayman Islands
law) binding on the Company prohibiting or restricting it from entering into and performing its obligations under the Documents.

2.9 No monies paid to or for the account of any party under the Documents or any property received or disposed
of by any party to the Documents in each case in connection with the Documents or the consummation of the transactions contemplated thereby
represent or will represent proceeds of criminal conduct or criminal property or terrorist property (as defined in the Proceeds of Crime
Act (As Revised) and the Terrorism Act (As Revised), respectively).

2.10 There is nothing under any law (other than the laws of the Cayman Islands) which would or might affect
the opinions set out below. Specifically, we have made no independent investigation of the Relevant Law.

Save as aforesaid we have not been instructed to undertake and have not undertaken any further enquiry or due diligence in relation to the transaction the subject of this opinion letter.

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| 3 | Opinions |

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Based upon, and subject to, the foregoing assumptions and the qualifications set out below, and having regard to such legal considerations as we deem relevant, we are of the opinion that:

3.1 The Company has been duly incorporated as an exempted company with limited liability and is validly existing
and in good standing with the Registrar of Companies under the laws of the Cayman Islands.

3.2 The Class A Ordinary Shares to be offered and issued by the Company as contemplated by the Registration
Statement have been duly authorised for issue, and when issued by the Company against payment in full of the consideration as set out
in the Registration Statement and in accordance with the terms set out in the Registration Statement, such Class A Ordinary Shares will
be validly issued, fully paid and non-assessable. As a matter of Cayman Islands law, a share is only issued when it has been entered in
the register of members (shareholders).

3.3 The execution, delivery and performance of the Unit Certificate and the Warrant Documents have been authorised
by and on behalf of the Company and, once the Unit Certificate and the Warrant Documents have been executed and delivered by any director
or officer of the Company, the Unit Certificate and the Warrant Documents will be duly executed and delivered on behalf of the Company
and will constitute the legal, valid and binding obligations of the Company enforceable in accordance with their terms.

4 Qualifications

The opinions expressed above are subject to the following qualifications:

4.1 The obligations assumed by the Company under the Documents will not necessarily be enforceable in all
circumstances in accordance with their terms. In particular:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) enforcement may be limited by bankruptcy, insolvency, liquidation, reorganisation, readjustment of debts
or moratorium or other laws of general application relating to protecting or affecting the rights of creditors and/or contributories;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) enforcement may be limited by general principles of equity. For example, equitable remedies such as specific
performance may not be available, *inter alia*, where damages are considered to be an adequate remedy;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c) where obligations are to be performed in a jurisdiction outside the Cayman Islands, they may not be enforceable
in the Cayman Islands to the extent that performance would be illegal under the laws of that jurisdiction; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d) some claims may become barred under relevant statutes of limitation or may be or become subject to defences
of set off, counterclaim, estoppel and similar defences.

4.2 To maintain the Company in good standing with the Registrar of Companies under the laws of the Cayman
Islands, annual filing fees must be paid and returns made to the Registrar of Companies within the time frame prescribed by law.

4.3 Under Cayman Islands law, the register of members (shareholders) is *prima facie* evidence of title
to shares and this register would not record a third party interest in such shares. However, there are certain limited circumstances where
an application may be made to a Cayman Islands court for a determination on whether the register of members reflects the correct legal
position. Further, the Cayman Islands court has the power to order that the register of members maintained by a company should be rectified
where it considers that the register of members does not reflect the correct legal position. As far as we are aware, such applications
are rarely made in the Cayman Islands and for the purposes of the opinion given in paragraph 3.2, there are no circumstances or matters
of fact known to us on the date of this opinion letter which would properly form the basis for an application for an order for rectification
of the register of members of the Company, but if such an application were made in respect of the Class A Ordinary Shares, then the validity
of such shares may be subject to re-examination by a Cayman Islands court.

4.4 In this opinion letter the phrase "non-assessable" means, with respect to the issuance of shares,
that a shareholder shall not, in respect of the relevant shares and in the absence of a contractual arrangement, or an obligation pursuant
to the memorandum and articles of association, to the contrary, have any obligation to make further contributions to the Company's assets
(except in exceptional circumstances, such as involving fraud, the establishment of an agency relationship or an illegal or improper purpose
or other circumstances in which a court may be prepared to pierce or lift the corporate veil).

We hereby consent to the filing of this opinion letter as an exhibit to the Registration Statement and to the references to our firm under the headings "Legal Matters", "Risk Factors", "Shareholders' Suits" and "Enforcement of Civil Liabilities" in the prospectus included in the Registration Statement. In providing our consent, we do not thereby 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 Commission thereunder.

We express no view as to the commercial terms of the Documents or whether such terms represent the intentions of the parties and make no comment with regard to warranties or representations that may be made by the Company.

The opinions in this opinion letter are strictly limited to the matters contained in the opinions section above and do not extend to any other matters. We have not been asked to review and we therefore have not reviewed any of the ancillary documents relating to the Documents and express no opinion or observation upon the terms of any such document.

This opinion letter is addressed to you and may be relied upon by you, your counsel and purchasers of Units pursuant to the Registration Statement. This opinion letter is limited to the matters detailed herein and is not to be read as an opinion with respect to any other matter.

Yours faithfully

Maples and Calder (Cayman) LLP

HCM III Acquisition Corp.

PO Box 309, Ugland House

Grand Cayman

KY1-1104

Cayman Islands

To: Maples and Calder (Cayman) LLP

PO Box 309, Ugland House

Grand Cayman

KY1-1104

Cayman Islands

30 July 2025

**HCM III Acquisition Corp.** (the "**Company**")

I, the undersigned, being a director of the Company, am aware that you are being asked to provide an opinion letter (the "**Opinion**") in relation to certain aspects of Cayman Islands law. Unless otherwise defined herein, capitalised terms used in this certificate have the respective meanings given to them in the Opinion. I hereby certify that:

1 The Memorandum and Articles remain in full force and effect and are unamended.

2 The Company has not entered into any mortgages or charges over its property or assets other than those entered in the register of mortgages and charges of the Company.

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| 3 | The shareholders of the Company (the "**Shareholders**") have not restricted the powers of the directors of the Company in any way. |

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4 The sole director of the Company at the date of the Resolutions and at the date of this certificate was and is as follows: Shawn Matthews.

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| 5 | The minute book and corporate records of the Company as maintained at its registered office in the Cayman Islands and made available to you are complete and accurate in all material respects (including, without limitation, with respect to the disclosure of interests (if any) by directors of the Company), and all minutes and resolutions filed therein represent a complete and accurate record of all meetings of the Shareholders and directors (or any committee thereof) of the Company (duly convened in accordance with the Memorandum and Articles) and all resolutions passed at the meetings or passed by written resolution or consent, as the case may be. |

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| 6 | Prior to, at the time of, and immediately following the approval of the transactions contemplated by the Registration Statement, the Company was, or will be, able to pay its debts as they fell, or fall, due and has entered, or will enter, into the transactions contemplated by the Registration Statement for proper value and not with an intention to defraud or wilfully defeat an obligation owed to any creditor or with a view to giving a creditor a preference. |

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| 7 | Each director of the Company considers the transactions contemplated by the Registration Statement to be of commercial benefit to the Company and has acted in good faith in the best interests of the Company, and for a proper purpose of the Company, in relation to the transactions which are the subject of the Opinion. |

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| 8 | To the best of my knowledge and belief, having made due inquiry, the Company is not the subject of legal, arbitral, administrative or other proceedings in any jurisdiction and neither the directors nor Shareholders have taken any steps to have the Company struck off or placed in liquidation. Further, no steps have been taken to wind up the Company or to appoint restructuring officers or interim restructuring officers, and no step has been taken to appoint a receiver in relation to any of the Company's property or assets. |

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9 To the best of my knowledge and belief, having made due inquiry, there are no circumstances or matters of fact existing which may properly form the basis for an application for an order for rectification of the register of members of the Company.

10 The Registration Statement has been, or will be, authorised and duly executed and delivered by or on behalf of all relevant parties in accordance with all relevant laws.

11 No invitation has been made or will be made by or on behalf of the Company to the public in the Cayman Islands to subscribe for any of the Class A Ordinary Shares.

12 The Class A Ordinary Shares to be issued pursuant to the Registration Statement have been, or will be, duly registered, and will continue to be registered, in the Company's register of members (shareholders).

13 The Company is not a central bank, monetary authority or other sovereign entity of any state and is not a subsidiary, direct or indirect, of any sovereign entity or state.

14 There is no contractual or other prohibition or restriction (other than as arising under Cayman Islands law) binding on the Company prohibiting or restricting it from entering into and performing its obligations under the Documents.

(Signature Page follows)

I confirm that you may continue to rely on this certificate as being true and correct on the day that you issue the Opinion unless I shall have previously notified you in writing personally to the contrary.

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| Signature: | /s/ Shawn Matthews |
| Name: | Shawn Matthews |
| Title: | Director |

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