<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 3)*
NORTH AMERICAN SCIENTIFIC, INC.
- --------------------------------------------------------------------------------
(Name of Issuer)
Common Stock
- --------------------------------------------------------------------------------
(Title of Class of Securities)
65715D100
----------------------------------
(CUSIP Number)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).
Page 1 of 4 pages
<PAGE>
SCHEDULE 13G
CUSIP No. 65715D100 Page 2 of 4 Pages
--------- ----- -----
- -------------------------------------------------------------------------------
(1) NAMES OF REPORTING PERSONS.
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS.
L. Michael Cutrer
- -------------------------------------------------------------------------------
(2) CHECK THE APPROPRIATE BOX IF A MEMBER (A) / /
OF A GROUP* (B) /X/
- -------------------------------------------------------------------------------
(3) SEC USE ONLY
- -------------------------------------------------------------------------------
(4) CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.
- -------------------------------------------------------------------------------
NUMBER OF SHARES (5) SOLE VOTING POWER
BENEFICIALLY 555,000*
OWNED BY --------------------------------------------------
EACH REPORTING (6) SHARED VOTING POWER
PERSON WITH: 0
--------------------------------------------------
(7) SOLE DISPOSITIVE POWER
555,000*
--------------------------------------------------
(8) SHARED DISPOSITIVE POWER
0
- -------------------------------------------------------------------------------
(9) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
555,000*
- -------------------------------------------------------------------------------
(10) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* /X/
- -------------------------------------------------------------------------------
(11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
7.51%
- -------------------------------------------------------------------------------
(12) TYPE OF REPORTING PERSON*
IN
- -------------------------------------------------------------------------------
*Includes 180,000 shares subject to outstanding options which are immediately
exercisable. Excludes 3,750 shares owned and 25,125 shares subject to
outstanding options which are deemed exercisable and which are held by
reporting person's spouse over which the reporting person disclaims
beneficial ownership. The information in this Form 13G reflects a 3 for 2
stock split effected in the form of a dividend effective April 20, 1998.
Page 2 of 4 Pages
<PAGE>
ITEM 1(a) Name of Issuer: North American Scientific, Inc.
ITEM 1(b) Address of Issuer's Principal Executive Offices:
20200 Sunburst Street
Chatsworth, CA 91311
ITEM 2(a) Name of Person Filing: L. Michael Cutrer
ITEM 2(b) Address of Principal Business Office:
20200 Sunburst Street
Chatsworth, CA 91311
ITEM 2(c) Citizenship: United States
ITEM 2(d) Title of Class of Securities
Common Stock, $0.01 par value per share
ITEM 2(e) CUSIP Number: 65715D100
ITEM 3 Not Applicable.
ITEM 4 Ownership:
The following information is provided as of December 31, 1998:
(a) Amount Beneficially Owned: 555,000*
(b) Percent of Class: 7.51%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: 555,000*
(ii) shared power to vote or to direct the vote: 0
(iii) sole power to dispose or to direct the disposition of:
555,000*
(iv) shared power to dispose or to direct the disposition of: 0
*Includes 180,000 shares subject to outstanding options which are immediately
exercisable. Excludes 3,750 shares owned and 25,125 shares subject to
outstanding options which are deemed exercisable and which are held by
reporting person's spouse over which the reporting person disclaims
beneficial ownership.
Page 3 of 4 Pages
<PAGE>
ITEM 5 Ownership of Five Percent or Less of a Class
Not Applicable
ITEM 6 Ownership of More than Five 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
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
Not Applicable
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.
Date: February 10, 1999
Signature /s/ L. Michael Cutrer
---------------------
Name/Title L. Michael Cutrer
Page 4 of 4 Pages
