<PAGE>
----------------------------
OMB APPROVAL
----------------------------
OMB Number 3235-0287
Expires: September 30, 1998
Estimated average burden
hours per response.......0.5
----------------------------
+--------+
| FORM 4 | U.S. SECURITIES AND EXCHANGE COMMISSION
+--------+ WASHINGTON, D.C. 20549
[_] Check this box if
no longer subject STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
to Section 16.
Form 4 or Form 5 Filed pursuant to Section 16(a) of the Securities
obligations may Exchange Act of 1934, Section 17(a) of the
continue. See Public Utility Holding Company Act of 1935 or
Instruction 1(b). Section 30(f) of the Investment Company Act of 1940
- --------------------------------------------------------------------------------
1. Name and Address of Reporting Person*
MEHRA AJAY
- --------------------------------------------------------------------------------
(Last) (First) (Middle)
C/O OSI SYSTEMS, INC.
12525 CHADRON AVENUE
- --------------------------------------------------------------------------------
(Street)
HAWTHORNE CA 90250
- --------------------------------------------------------------------------------
(City) (State) (Zip)
2. Issuer Name and Ticker or Trading Symbol OSI SYSTEMS, INC. OSIS
-----------------------------------
3. IRS or Social Security Number of Reporting Person (Voluntary)
--------------
4. Statement for Month/Year DECEMBER 1997
---------------------------------------------------
5. If Amendment, Date of Original (Month/Year)
---------------------------------
6. Relationship of Reporting Person to Issuer (Check all applicable)
[X] Director [X] Officer [ ] 10% Owner [ ] Other
(give title below) (specify below)
VICE PRESIDENT, CFO & SEC.
----------------------------------------------------------------------------
7. Individual or Joint/Group Filing (Check applicable line)
[X] Form filed by One Reporting Person
[ ] Form filed by More than One Reporting Person
* If the Form is filed by more than one Reporting Person, see Instruction
4(b)(v).
TABLE I--NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
<TABLE>
<CAPTION>
- ------------------------------------------------------------------------------------------------------------------------------------
1. Title 2. Trans- 3. Trans- 4. Securities Acquired (A) 5. Amount of 6. Owner- 7. Nature
of action action or Disposed of (D) Securities ship of In-
Security Date Code (Instr. 3, 4 and 5) Beneficially Form: direct
(Instr. 3) (Month/ (Instr. 8) Owned at Direct Bene-
Day/ ----------------------------------------------- End of (D) or ficial
Year) Month Indirect Owner-
Code V Amount (A) or Price (Instr. 3 and 4) (I) ship
(D) (Instr. 4) (Instr. 4)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
COMMON STOCK 1-9-98 M 9,910 A $1.87 $135,964 D
- ------------------------------------------------------------------------------------------------------------------------------------
1-9-98 M 30,000 A $2.33 $165,964 D
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
</TABLE>
Reminder: Report on a separate line for each class of securities beneficially
owned directly or indirectly. (Print or Type Responses)
<PAGE>
FORM 4 (continued)
TABLE II--DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(e.g., puts, calls, warrants, options, convertible securities)
<TABLE>
<CAPTION>
- -----------------------------------------------------------------------------------------------------------------------------
1. Title of Derivative 2. Conver- 3. Trans- 4. Transac- 5. Number of Deriv-
Security (Instr. 3) sion or action tion Code ative Securities
Exercise Date (Instr. 8) Acquired (A) or
Price of (Month/ Disposed (D) of
Deriv- Day/ (Instr. 3, 4, and 5)
ative Year)
Security
---------------------------------------------------
Code V (A) (D)
- -----------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C>
EMPLOYEE STK OPT $1.87 1-9-98 M 9,910
- -----------------------------------------------------------------------------------------------------------------------------
EMPLOYEE STK OPT $2.33 1-9-98 M 30,000
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
</TABLE>
TABLE II--DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(e.g., puts, calls, warrants, options, convertible securities)--CONTINUED
<TABLE>
<CAPTION>
- ------------------------------------------------------------------------------------------------------------------------------------
1. Title of Derivative 6. Date Exer- 7. Title and Amount of 8. Price 9. Number 10. Owner- 11. Na-
Security (Instr. 3) cisable and Underlying Securities of of Deriv- ship ture
Expiration (Instr. 3 and 4) Deriv- ative Form of In-
Date ative Secur- of De- direct
(Month/Day/ Secur- ities rivative Bene-
Year) ity Bene- Secu- ficial
(Instr. ficially rity: Owner-
-------------------------------------------- 5) Owned Direct ship
Date Expira- Amount or at End (D) or (Instr.
Exer- tion Title Number of of Indi- 4)
cisable Date Shares Month rect (1)
(Instr. 4) (Instr. 4)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C>
EMPLOYEE STK OPT (1) 3/1/98 common stock 9,910 $1.87
- ------------------------------------------------------------------------------------------------------------------------------------
EMPLOYEE STK OPT (1) 10/1/98 common stock 30,000 $2.33
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
</TABLE>
Explanation of Responses:
(1) ENTIRE EMPLOYEE STOCK OPTION IS VESTED
**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 provided is insufficient, see Instruction 6 for procedure.
/s/ Ajay Mehra 2/6/98
------------------------------- -----------------
**Signature of Reporting Person Date
