# EDGAR Filing Document

**Accession Number:** 0001374339
**File Stem:** 0001903360-26-000013
**Filing Date:** 2026-3
**Character Count:** 9295
**Document Hash:** 692f6fe71abda58a57de4f5eed628dae
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001903360-26-000013.hdr.sgml**: 20260318

**ACCESSION NUMBER**: 0001903360-26-000013

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13G

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260318

**DATE AS OF CHANGE**: 20260318

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ProMIS Neurosciences Inc.
- **CENTRAL INDEX KEY:** 0001374339
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** Z4
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-93797
- **FILM NUMBER:** 26767305

**BUSINESS ADDRESS:**
- **STREET 1:** SUITE 200, 1920 YONGE STREET
- **CITY:** TORONTO
- **STATE:** A6
- **ZIP:** M4S 3E2
- **BUSINESS PHONE:** 416-847-6898

**MAIL ADDRESS:**
- **STREET 1:** SUITE 200, 1920 YONGE STREET
- **CITY:** TORONTO
- **STATE:** A6
- **ZIP:** M4S 3E2

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** AMORFIX LIFE SCIENCES LTD
- **DATE OF NAME CHANGE:** 20060831
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Wellington Biomedical Innovation Master Investors (Cayman) II L.P.
- **CENTRAL INDEX KEY:** 0001903360

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** E9

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G

**BUSINESS ADDRESS:**
- **STREET 1:** 280 CONGRESS STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210
- **BUSINESS PHONE:** 617-951-5000

**MAIL ADDRESS:**
- **STREET 1:** 280 CONGRESS STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210

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

## SCHEDULE 13G

### Under the Securities Exchange Act of 1934

**Issuer:** ProMIS Neurosciences, Inc.

**Title of Class of Securities:** Common Stock

**CUSIP Number:** —

**Date of Event Which Requires Filing of this Statement:** 03/11/2026

**Check the appropriate box to designate the rule pursuant to which this Schedule is filed:**

- [ ] Rule 13d-1(b)

- [x] Rule 13d-1(c)

- [ ] Rule 13d-1(d)

---

| 1. | Names of Reporting Persons<br>Wellington Biomedical Innovation Master Investors (Cayman) II, L.P. | Names of Reporting Persons<br>Wellington Biomedical Innovation Master Investors (Cayman) II, L.P. |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>X1 | Citizenship or Place of Organization<br>X1 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>895877 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>895877 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>895877.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>895877.00 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>9.99% | Percent of Class Represented by Amount in Row (9)<br>9.99% |
| 12. | Type of Reporting Person (See Instructions)<br>PN | Type of Reporting Person (See Instructions)<br>PN |

---

**Item 1(a). Name of Issuer:**
ProMIS Neurosciences, Inc.

**Item 1(b). Address of Issuer's Principal Executive Offices:**
Suite 200, 1920 Yonge Street, Toronto ON M4S 3E2

**Item 2(a). Name of Person Filing:**
Wellington Biomedical Innovation Master Investors (Cayman) II, L.P.

**Item 2(b). Address of Principal Business Office:**
c/o Wellington Management Company LLP, 280 Congress Street, Boston MA 02210

**Item 2(c). Citizenship:**
Cayman Islands

**Item 2(d). Title of Class of Securities:**
Common Stock

**Item 2(e). CUSIP Number:**
—

**Item 3. If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:**

(a) [ ] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b) [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c) [ ] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d) [ ] Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e) [ ] An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);

(f) [ ] An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);

(g) [ ] A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h) [ ] A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i) [ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j) [ ] A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), if filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:

(k) [ ] Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).

**Item 4. Ownership:**

**(a) Amount beneficially owned:**

Wellington Biomedical Innovation Master Investors (Cayman) II L.P. may be deemed to beneficially own an aggregate of 895,877 shares (the "Shares") of Common Stock, of ProMIS Neurosciences Inc. (the "Issuer"). The 895,877 Shares reported as beneficially owned on this Schedule 13G consists of (i) 696,378 Shares held directly by Wellington Biomedical Innovation Master Investors (Cayman) II L.P., (ii) 199,499 Shares underlying warrants (the "Warrants") held directly by Wellington Biomedical Innovation Master Investors (Cayman) II L.P. The securities beneficially owned by each Filer excludes 496,879 Shares underlying Warrants which contain an issuance limitation that prohibits the holder from exercising the Warrants to the extent that after giving effect to such issuance after the exercise, the holder (together with the holder's affiliates and any other persons acting as a group together with the holder or any of the holder's affiliates, including the other Filers) would beneficially own in excess of 9.99% of the Shares outstanding immediately after giving effect to the issuance of the Shares issuable upon exercise of the Warrants. As a result, Wellington Biomedical Innovation Master Investors (Cayman) II L.P. beneficially owns 9.99% of the outstanding Shares of the Issuer. Ownership percentages are based on approximately 8,967,740 shares of Common Stock outstanding, comprised of (i) 2,152,444 shares of Common Shares outstanding, following a one-for-twenty-five reverse stock split effective as of November 28, 2025 reported by the Issuer in Exhibit 99.1 to its Form 8-K filed with the SEC on November 24, 2025 and (ii) 6,815,296 shares of Common Stock reported by the Issuer as issued as of February 3, 2026 in the Issuer's Form 8-K filed with the SEC on January 30, 2026.

**(b) Percent of class:**

9.99

**(c) Number of shares as to which the person has:**

**(i) Sole power to vote or to direct the vote:**

0

**(ii) Shared power to vote or to direct the vote:**

895,877

**(iii) Sole power to dispose or to direct the disposition of:**

0

**(iv) Shared power to dispose or to direct the disposition of:**

895,877

**Item 5. Ownership of Five Percent or Less of a Class.**

[x] If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following.

**Item 6. Ownership of More than 5 Percent on Behalf of Another Person.**

Not Applicable

**Item 7. Identification and Classification of the Subsidiary**

Not Applicable

**Item 8. Identification and Classification of Members of the Group**

Not Applicable

**Item 9. Notice of Dissolution of Group**

Not Applicable

**Item 10. Certification:**

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

### SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Wellington Biomedical Innovation Master Investors (Cayman) II, L.P.**

**Date:** 03/18/2026

**By:** Ihsan Speede

**Name & Title:** Authorized Person