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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.
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(Name of Issuer)
Common Stock
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(Title of Class of Securities)
65715D100
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(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
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SCHEDULE 13G
CUSIP No. 65715D100 Page 2 of 4 Pages
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(1) NAMES OF REPORTING PERSONS.
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS
Irwin J. Gruverman
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(2) CHECK THE APPROPRIATE BOX IF A MEMBER (A) / /
OF A GROUP (B) /X/
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(3) SEC USE ONLY
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(4) CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.
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NUMBER OF SHARES (5) SOLE VOTING POWER
BENEFICIALLY 460,600*
OWNED BY --------------------------------------------------
EACH REPORTING (6) SHARED VOTING POWER
PERSON WITH: 0
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(7) SOLE DISPOSITIVE POWER
460,600*
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(8) SHARED DISPOSITIVE POWER
0
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(9) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
460,600*
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(10) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* /X/
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(11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.7%
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(12) TYPE OF REPORTING PERSON*
IN
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*Includes 31,000 shares held in a fund of which the reporting person is the
sole general partner, and 45,000 shares subject to outstanding options which
are currently exercisable. Excludes 30,000 shares owned by reporting person's
spouse, as to which 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.
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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
Irwin J. Gruverman
ITEM 2(b) Address of Principal Business Office
30 Ossipee Road
Newton, MA 02464
ITEM 2(c) Citizenship
United States
ITEM 2(d) Title of Class of Securities
Common Stock, $0.01 par value
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:
460,600*
(b) Percent of class:
6.7%
(c) Number of shares as to which the person has:
(i) sole power to vote or to direct the vote
460,600*
(ii) shared power to vote or to direct the vote
0
(iii) sole power to dispose or to direct the disposition of
460,600*
(iv) shared power to dispose or to direct the disposition of
0
*Includes 31,000 shares held in a fund of which the reporting person is the
sole general partner, 45,000 shares subject to outstanding options which are
immediately exercisable. Excludes 30,000 shares owned by reporting person's
spouse, as to which reporting person disclaims beneficial ownership.
Page 3 of 4 Pages
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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 12, 1999
Signature: /s/ Irwin J. Gruverman
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Name/Title: Irwin J. Gruverman
Page 4 of 4 Pages
