<PAGE>
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
----------------------
SCHEDULE 13D
Under the Securities Exchange Act of 1934
(Amendment No. 1)
North American Scientific, Inc.
-------------------------------
(Name of Issuer)
Common Stock, $0.01 par value
-----------------------------
(Title of Class of Securities)
65715D100
---------
(CUSIP Number)
Andrew S. Paul, Esq.
c/o Tudor Investment Corporation
One Liberty Plaza (51st Floor)
New York, New York 10006
(212) 602-6700
--------------
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
May 7, 1998
-----------
(Date of Event which Requires Filing of this Statement)
If the filing person has previously filed a statement on Schedule 13G to
report the acquisition which is the subject of this Schedule 13D, and is filing
this schedule because of Rule 13d-1(b)(3) or (4), check the following box [ ].
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- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Tudor Investment Corporation
TIN: 22-2514825
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[X]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 249,470
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
249,470
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
249,470
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
3.9%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
CO
- -----------------------------------------------------------------
<PAGE>
- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Paul Tudor Jones, II
TIN:
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
United States of America
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 260,100
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
260,100
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
260,100
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
4.1%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
IN
- -----------------------------------------------------------------
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- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
The Raptor Global Fund Ltd.
TIN: n/a
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Cayman Islands
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 98,090
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
98,090
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
98,090
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
1.5%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
CO
- -----------------------------------------------------------------
<PAGE>
- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
The Raptor Global Fund L.P.
TIN: 13-3735415
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 34,470
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
34,470
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
34,470
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
0.5%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
PN
- -----------------------------------------------------------------
<PAGE>
- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Tudor Arbitrage Partners L.P.
TIN: 13-3496979
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 10,630
EACH ----------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
10,630
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
10,630
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
0.2%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
PN
- -----------------------------------------------------------------
<PAGE>
- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Tudor Global Trading LLC
TIN: 13-3862744
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 10,630
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
10,630
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
10,630
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
0.2%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
OO
- -----------------------------------------------------------------
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- --------------------
CUSIP NO. 65715D100
- --------------------
- -----------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Tudor BVI Futures, Ltd.
TIN: n/a
- -----------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [_]
(b) [X]
- -----------------------------------------------------------------
3. SEC USE ONLY
- -----------------------------------------------------------------
4. SOURCE OF FUNDS
OO
- -----------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
[_]
- -----------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION
British Virgin Islands
- -----------------------------------------------------------------
7 SOLE VOTING POWER
NUMBER OF 0
SHARES ------------------------------------------
BENEFICIALLY 8 SHARED VOTING POWER
OWNED BY 116,910
EACH ------------------------------------------
REPORTING 9 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------
10 SHARED DISPOSITIVE POWER
116,910
- -----------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
PERSON
116,910
- -----------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES
[_]
- -----------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
1.8%
- -----------------------------------------------------------------
14 TYPE OF REPORTING PERSON
CO
- -----------------------------------------------------------------
<PAGE>
Item 1. Security and Issuer
-------------------
This Amendment No. 1, dated May 12, 1998, to Statement on Schedule 13D,
relates to the Common Stock, $0.01 par value per share ("Common Stock"), of
North American Scientific, Inc., a Delaware corporation (the "Company"), and is
filed by Tudor Investment Corporation, a Delaware corporation ("TIC"), Paul
Tudor Jones, II, a natural person and a citizen of the United States ("Mr.
Jones"), The Raptor Global Fund Ltd., a company organized under the laws of the
Cayman Islands ("Raptor Ltd."), The Raptor Global Fund L.P., a Delaware limited
partnership ("Raptor L.P."), Tudor Arbitrage Partners L.P., a Delaware limited
partnership ("TAP"), Tudor Global Trading LLC, a Delaware limited liability
company ("TGT"), and Tudor BVI Futures, Ltd., a corporation organized under the
laws of the British Virgin Islands ("Tudor BVI" and collectively with TIC, Mr.
Jones, Raptor Ltd., Raptor L.P., TAP and TGT, the "Reporting Persons").* The
summary of information on the schedule attached hereto is qualified in its
entirety by reference to such schedule, which is incorporated by reference
herein.
The Company's principal executive offices are located at 7435 Greenbush
Avenue, North Hollywood, CA 91605.
Item 5. Interest in Securities of the Issuer.
-------------------------------------
Attached hereto as Schedule I is a list of the transactions by each of
the Reporting Persons in Common Stock within the past sixty days.
Because TIC is the sole general partner of Raptor L.P. and provides
investment advisory services to Raptor Ltd., Raptor L.P. and Tudor BVI, TIC may
be deemed to beneficially own the shares of Common Stock owned by each of such
Reporting Persons. TGT, as the sole general partner of TAP, may be deemed to
beneficially own the shares of Common Stock owned by TAP. In addition, because
Mr. Jones owns a majority of the capital stock and voting securities of TIC and
indirectly owns a majority of the equity interests in TGT, Mr. Jones may be
deemed to beneficially own the shares of Common Stock deemed beneficially owned
by TIC and TGT.
Based on information contained in the Company's Form 10QSB for the
quarter ended January 31, 1998 that there were 6,400,802 shares of Common Stock
issued and outstanding as of March 13, 1998 (adjusted for a 3 for 2 stock split
subsequent to such date), each Reporting Person beneficially owns (or, with
- -------------------------
* For purposes of this Statement on Schedule 13D the Reporting Persons have
filed as a "group". Nevertheless, the Reporting Persons hereby disclaim that
they are members of a "group" for purposes of Section 13(d) of the Securities
Exchange Act of 1934 or for any other purpose.
<PAGE>
respect to TIC, Mr. Jones and TGT, may be deemed to beneficially own) the number
and percentage of outstanding shares of Common Stock listed in the responses to
Items 11 and 13, respectively, of the cover page filed herewith for such
Reporting Person. In addition, the number of shares of Common Stock beneficially
owned (or, with respect to TIC, Mr. Jones and TGT, which may be deemed
beneficially owned) by each Reporting Person with respect to which such
Reporting Person (i) has sole voting power, (ii) shares voting power, (iii) has
sole dispositive power and (iv) shares dispositive power are listed in the
responses to Items 7, 8, 9 and 10, respectively, of the cover page filed
herewith for such Reporting Person. The voting and dispositive power is reported
as shared because each of Raptor Ltd., Raptor L.P. and Tudor BVI has the power
to remove TIC as its investment advisor or general partner and because TAP has
the power to remove TGT as its general partner. Each of Raptor Ltd., Raptor
L.P., TAP and Tudor BVI expressly disclaim beneficial ownership of the shares of
Common Stock beneficially owned by any other such Reporting Person and each of
TIC, Mr. Jones and TGT disclaim beneficial ownership of the Common Stock
beneficially owned by Raptor Ltd., Raptor L.P., TAP and Tudor BVI and, in the
case of Mr. Jones, TIC and TGT.
Following the sales reported on Schedule I, none of the Reporting Persons
remained the beneficial owner, pursuant to Rule 13(d)(1)(i), of more than 5% of
the Common Stock of the Company.
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SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this Amendment No. 1 to Statement on
Schedule 13D is true, complete and correct.
Dated: May 12, 1998
TUDOR INVESTMENT CORPORATION
By: \s\ Andrew S. Paul
--------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
\s\ Paul Tudor Jones, II
------------------------------
Paul Tudor Jones, II
THE RAPTOR GLOBAL FUND LTD.
By: TUDOR INVESTMENT CORPORATION,
Trading Advisor
By: \s\ Andrew S. Paul
-------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
THE RAPTOR GLOBAL FUND L.P.
By: TUDOR INVESTMENT CORPORATION,
General Partner
By: \s\ Andrew S. Paul
-------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
<PAGE>
TUDOR ARBITRAGE PARTNERS L.P.
By: TUDOR GLOBAL TRADING LLC,
General Partner
By: \s\ Andrew S. Paul
------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
TUDOR GLOBAL TRADING LLC
By: \s\ Andrew S. Paul
---------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
TUDOR BVI FUTURES, LTD.
By: TUDOR INVESTMENT CORPORATION,
Trading Advisor
By: \s\ Andrew S. Paul
------------------------
Name: Andrew S. Paul
Title: Vice President &
General Counsel
<PAGE>
Schedule I
TRANSACTIONS
All shares of Common Stock were sold in connection with the Exchange.
Tudor BVI
- ---------
Date Transaction # Shares $/Share
- ---- ----------- -------- -------
05/06/98 Sale 27,660 $29.5021
05/07/98 Sale 41,880 $29.1250
Total Common Stock beneficially owned as of
the date of this Schedule 13D: 116,910
Raptor L.P.
- -----------
Date Transaction # Shares $/Share
- ---- ----------- -------- -------
05/06/98 Sale 11,070 $29.5021
05/07/98 Sale 22,410 $29.1250
Total Common Stock beneficially owned as of
the date of this Schedule 13D: 34,470
TAP
- ---
Date Transaction # Shares $/Share
- ---- ----------- -------- -------
05/06/98 Sale 5,410 $29.5021
05/07/98 Sale 6,910 $29.1250
Total Common Stock beneficially owned as of
the date of this Schedule 13D: 10,630
Raptor Ltd.
- -----------
Date Transaction # Shares $/Share
- ---- ----------- -------- -------
05/06/98 Sale 25,760 $29.5021
05/07/98 Sale 63,800 $29.1250
Total Common Stock beneficially owned as of
the date of this Schedule 13D: 98,090
