Mawer reports 4.73% OSI Systems (OSIS) stake on amended 13G

Rhea-AI Filing Summary

Mawer Investment Management Ltd. filed an amended Schedule 13G reporting beneficial ownership of 803,602 shares of OSI Systems, Inc. common stock, representing 4.73% of the class as of an outstanding share count reported on October 24, 2025. Mawer has sole power to vote and dispose of all 803,602 shares and no shared voting or dispositive power. The firm certifies the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of OSI Systems.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

OSI SYSTEMS INC

(Name of Issuer)

Common Stock

(Title of Class of Securities)

671044105

(CUSIP Number)

12/31/2025

(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)

SCHEDULE 13G

CUSIP No. 671044105

1

Names of Reporting Persons

Mawer Investment Management Ltd.

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

ALBERTA, CANADA

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 803,602.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 803,602.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

803,602.00

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)

4.73 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: Based upon 16,977,873 Common Stock of OSI Systems, Inc. (the "Issuer") outstanding as of October 24, 2025, as reported in the Issuer's Form 10-Q (Quarterly Report) filed with the Securities and Exchange Commission on October 30, 2025.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: OSI SYSTEMS INC
(b)	Address of issuer's principal executive offices: 12525 Chadron Ave., Hawthorne, California, 90250
Item 2.
(a)	Name of person filing: Mawer Investment Management Ltd.
(b)	Address or principal business office or, if none, residence: 600, 517 - 10th Avenue SW Calgary, Alberta, Canada T2R 0A8
(c)	Citizenship: Canada
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 671044105
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: 803,602
(b)	Percent of class: 4.73%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 803,602
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 803,602
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	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.

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.

Mawer Investment Management Ltd.

Signature:	/s/ John Wilson, Portfolio Manager
Name/Title:	Mawer Investment Management Ltd.
Date:	01/23/2026

FAQ

What percentage of OSI Systems (OSIS) does Mawer Investment Management own?

Mawer Investment Management Ltd. reports beneficial ownership of 4.73% of OSI Systems common stock. This percentage is based on 16,977,873 shares outstanding as of October 24, 2025, as disclosed in OSI Systems’ Form 10-Q filed on October 30, 2025.

How many OSI Systems (OSIS) shares are held by Mawer Investment Management?

Mawer Investment Management Ltd. beneficially owns 803,602 OSI Systems common shares. The firm reports sole voting and sole dispositive power over all 803,602 shares, with no shared authority to vote or dispose of any additional OSI Systems shares.

Does Mawer Investment Management seek control of OSI Systems (OSIS)?

Mawer Investment Management Ltd. states the OSI Systems shares were acquired and are held in the ordinary course of business. It certifies they were not acquired to change or influence control of OSI Systems or in connection with any transaction having that purpose or effect.

What type of filing did Mawer submit regarding OSI Systems (OSIS)?

Mawer Investment Management Ltd. submitted an Amendment No. 1 to Schedule 13G for OSI Systems common stock. This filing updates its beneficial ownership position as of December 31, 2025, under the passive ownership reporting framework rather than an activist Schedule 13D.

What voting and dispositive powers does Mawer have over OSI Systems (OSIS) shares?

Mawer Investment Management Ltd. reports sole power to vote and dispose of 803,602 OSI Systems shares. It lists zero shared voting power and zero shared dispositive power, indicating all authority over these shares rests with Mawer alone.