Janus Henderson (PMN) discloses 14.4% holding in PROMIS Neurosciences

Rhea-AI Filing Summary

Janus Henderson Group plc reported beneficial ownership of 1,292,757 common shares of PROMIS Neurosciences Inc. The filing (Schedule 13G) states this represents 14.4% of the class as of 03/31/2026 with shared voting and dispositive power over those shares. The filing is signed on 04/07/2026.

Key Figures

Beneficial ownership: 1,292,757 shares Percent of class: 14.4% Reporting date: 03/31/2026 +4 more

7 metrics

Beneficial ownership 1,292,757 shares Amount beneficially owned as stated in Schedule 13G

Percent of class 14.4% Percent of common shares as stated in the filing (as of 03/31/2026)

Reporting date 03/31/2026 Ownership date shown on the Schedule 13G cover

CUSIP 74346M505 CUSIP for PROMIS common shares shown on the filing

Shared voting power 1,292,757 Number of shares with shared voting power reported

Shared dispositive power 1,292,757 Number of shares with shared dispositive power reported

Signature date 04/07/2026 Date the filing was signed by Head of North America Compliance

Key Terms

Schedule 13G, Beneficial owner, Shared dispositive power, Managed Portfolios, +1 more

5 terms

Schedule 13G regulatory

"Item 1. | (a) | Name of issuer: PROMIS NEUROSCIENCES INC."

A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.

Beneficial owner regulatory

"Item 4. | Ownership (a) | Amount beneficially owned: Janus Henderson Group plc ... beneficial owner of 1,292,757 common shares"

A beneficial owner is the person who ultimately owns or controls a financial asset or property, even if their name isn't directly on official documents. Think of it like someone who secretly holds the keys to a safe deposit box—others may appear to have access, but the true owner is the one who benefits from what's inside. Identifying beneficial owners helps ensure transparency and prevent illegal activities like money laundering or fraud.

Shared dispositive power regulatory

"(iv) Shared power to dispose or to direct the disposition of: 1292757"

Managed Portfolios financial

"the Asset Managers generally exercise investment and/or voting discretion on behalf of their clients which include ... Managed Portfolios"

Investment Company Act regulatory

"A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 ..."

The Investment Company Act is a law that sets rules for businesses whose main activity is managing and selling pooled money, such as mutual funds and other investment funds. It matters to investors because it requires clear reporting, limits managers from putting their own interests ahead of clients, and mandates safekeeping and oversight of assets—similar to safety inspections and traffic rules that help keep shared vehicles reliable and trustworthy.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

PROMIS NEUROSCIENCES INC.

(Name of Issuer)

Common Shares

(Title of Class of Securities)

74346M505

(CUSIP Number)

03/31/2026

(Date of Event Which Requires Filing of this Statement)

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

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): 74346M505

1

Names of Reporting Persons

JANUS HENDERSON GROUP PLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

JERSEY

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 1,292,757.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 1,292,757.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,292,757.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

14.4 %

12

Type of Reporting Person (See Instructions)

HC

SCHEDULE 13G

Item 1.
(a)	Name of issuer: PROMIS NEUROSCIENCES INC.
(b)	Address of issuer's principal executive offices: 1920 YONGE STREET, SUITE 200 TORONTO, ONTARIO, CANADA M4S 3E2
Item 2.
(a)	Name of person filing: Janus Henderson Group plc
(b)	Address or principal business office or, if none, residence: 201 Bishopsgate EC2M 3AE, United Kingdom
(c)	Citizenship: Y9
(d)	Title of class of securities: Common Shares
(e)	CUSIP Number(s): 74346M505
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: Janus Henderson Group plc (JHG) is the ultimate parent of a number of SEC-registered investment advisers and foreign equivalents thereof, including but not limited to Janus Henderson Investors US LLC, Janus Henderson Investors UK Limited, Janus Henderson Investors Australia Institutional Funds Management Limited, Janus Henderson Investors Middle East Limited, Janus Henderson Investors (Jersey) Limited, Janus Henderson Investors (Japan) Limited, Janus Henderson Investors (Singapore) Limited, Kapstream Capital Pty Limited, Privacore Capital Advisors LLC, Tabula Investment Management Limited, and Victory Park Capital Advisors LLC (each, an Asset Manager and together, the Asset Managers). The Asset Managers generally exercise investment and/or voting discretion on behalf of their clients which include investment companies, other investment advisers, institutional separate accounts and retail separate accounts (collectively referred to herein as Managed Portfolios). As a result of their exercise of investment and/or voting discretion on behalf of the Managed Portfolios, the Asset Managers may be deemed to be the beneficial owner of 1,292,757 common shares of Promis Neurosciences Inc. However, the Asset Managers do not have the right to receive any dividends from, or the proceeds from the sale of, the securities held in the Managed Portfolios and disclaim any ownership associated with such rights.
(b)	Percent of class: 14.4 %
(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: 1292757
	(iii) Sole power to dispose or to direct the disposition of: 0
	(iv) Shared power to dispose or to direct the disposition of: 1292757
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. The Managed Portfolios have the right to receive all dividends from, and the proceeds from the sale of, the securities held in their respective accounts. Of the Managed Portfolios, only the Janus Henderson Biotech Innovation Master Fund Ltd. has the right to receive dividends from, or the proceeds from the sale of, more than five percent of the common shares of Promis Neurosciences Inc. Due to an irrevocable delegation of investment and voting discretion to an Asset Manager on less than 60 days notice, the Fund is not considered a Reporting Person under Section 13(d) and (g).
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. Please refer to Exhibit 99.
Item 8.	Identification and Classification of Members of the Group.
	If a group has filed this schedule pursuant to §240.13d-1(b)(1)(ii)(K), so indicate under Item 3(k) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to §240.13d-1(c) or §240.13d-1(d), attach an exhibit stating the identity of each member of the group. N/A
Item 9.	Notice of Dissolution of Group.
	Notice of dissolution of a group may be furnished as an exhibit stating the date of the dissolution and that all further filings with respect to transactions in the security reported on will be filed, if required, by members of the group, in their individual capacity. See Item 5. N/A

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and 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.

JANUS HENDERSON GROUP PLC

Signature:	Kristin Mariani
Name/Title:	Head of North America Compliance
Date:	04/07/2026

Exhibit Information

Exhibit 24: Power of Attorney Exhibit 99: Item 7

FAQ

How many PROMIS (PMN) shares does Janus Henderson report owning?

Janus Henderson reports beneficial ownership of 1,292,757 shares. The Schedule 13G states this amount and ties it to the Asset Managers that exercise voting and investment discretion on behalf of Managed Portfolios as described in the filing.

What percentage of PROMIS common stock does Janus Henderson (PMN) hold?

The filing shows a 14.4% stake. Schedule 13G lists the percent of class as 14.4% as of 03/31/2026, reflecting the combined holdings for the Asset Managers under Janus Henderson Group plc.

Does Janus Henderson have sole voting or dispositive power over these PMN shares?

No sole power is reported. The Schedule 13G states Janus Henderson has 0 shares of sole voting or sole dispositive power and reports 1,292,757 as shared voting and shared dispositive power.

Which Janus Henderson fund holds more than 5% of PROMIS (PMN)?

Janus Henderson Biotech Innovation Master Fund Ltd. is identified. The filing states this Fund has the right to receive dividends or proceeds for more than 5% of the common shares among the Managed Portfolios described.

What is the relevant CUSIP and reporting date on the Schedule 13G for PROMIS?

The CUSIP is 74346M505 and the ownership date is 03/31/2026. These identifiers appear on the Schedule 13G cover lines and tie the reported holdings to PROMIS Neurosciences Inc.