<PAGE>
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
______________________________
SCHEDULE 13D
(Rule 13d-101)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(a) AND
AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a)
(Amendment No. 3)
BioSource International, Inc.
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(Name of Issuer)
Common Stock, par value $0.001 per share
--------------------------------------------------------------------------------
(Title of Class of Securities)
09066H104
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(CUSIP Number)
Genstar Capital LLC
555 California Street, Suite 4850
San Francisco, California 94104
(415) 834-2350
--------------------------------------------------------------------------------
(Name, Address and Telephone Number of Person Authorized to Receive Notices and
Communications)
Copy to:
Scott R. Haber
Latham & Watkins
505 Montgomery Street, Suite 1900
San Francisco, California 94111-2562
(415) 391-0600
August 2, 2000
--------------------------------------------------------------------------------
(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(e), 13d-1(f), or 13d-1(g),
check the following box [_].
(Continued on following pages)
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------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 2 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Genstar Capital LLC
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
------------------------------------------------------------------------------
4. Source of Funds
AF, OO
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5. Check Box if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e) [_]
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6. Citizenship or Place of Organization
Delaware
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7. Sole Voting Power
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-2,967,220- shares of Common Stock (includes 1,456,976
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 1,262,542 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-2,967,220- shares of Common Stock (includes 1,456,976
shares of Common Stock issuable upon conversion of
Preferred Stock and 1,262,542 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-2,967,220- shares of Common Stock (includes 1,456,976 shares of Common
Stock issuable upon conversion of Preferred Stock and 1,262,542 shares of
Common Stock issuable upon exercise of Warrants)
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12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
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13. Percent of Class Represented by Amount in Row (11)
26.6%
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14. Type of Reporting Person
OO
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2
<PAGE>
------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 3 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Genstar Capital Partners II, L.P.
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
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4. Source of Funds
AF, OO
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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
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-2,967,220- shares of Common Stock (includes 1,456,976
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 1,262,542 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-2,967,220- shares of Common Stock (includes 1,456,976
shares of Common Stock issuable upon conversion of
Preferred Stock and 1,262,542 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-2,967,220- shares of Common Stock (includes 1,456,976 shares of Common
Stock issuable upon conversion of Preferred Stock and 1,262,542 shares of
Common Stock issuable upon exercise of Warrants)
------------------------------------------------------------------------------
12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
------------------------------------------------------------------------------
13. Percent of Class Represented by Amount in Row (11)
26.6%
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14. Type of Reporting Person
PN
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3
<PAGE>
------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 4 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Stargen II LLC
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
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4. Source of Funds
AF, OO
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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
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7. Sole Voting Power
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-57,480- shares of Common Stock (includes 28,224
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 24,458 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-57,480- shares of Common Stock (includes 28,224
shares of Common Stock issuable upon conversion of
Preferred Stock and 24,458 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-57,480- shares of Common Stock (includes 28,224 shares of Common Stock
issuable upon conversion of Preferred Stock and 24,458 shares of Common
Stock issuable upon exercise of Warrants)
------------------------------------------------------------------------------
12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
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13. Percent of Class Represented by Amount in Row (11)
0.7%
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14. Type of Reporting Person
OO
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4
<PAGE>
------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 5 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Jean-Pierre L. Conte
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
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4. Source of Funds
PF, AF
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5. Check Box if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e) [_]
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6. Citizenship or Place of Organization
United States of America
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7. Sole Voting Power
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-3,024,700- shares of Common Stock (includes 1,485,200
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-3,024,700- shares of Common Stock (includes 1,485,200
shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-3,024,700- shares of Common Stock (includes 1,485,200 shares of Common
Stock issuable upon conversion of Preferred Stock and 1,287,000 shares of
Common Stock issuable upon exercise of Warrants)
------------------------------------------------------------------------------
12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
------------------------------------------------------------------------------
13. Percent of Class Represented by Amount in Row (11)
27.0%
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14. Type of Reporting Person
IN
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5
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------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 6 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Richard F. Hoskins
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
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4. Source of Funds
PF, AF
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5. Check Box if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e) [_]
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6. Citizenship or Place of Organization
United States of America
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7. Sole Voting Power
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-3,024,700- shares of Common Stock (includes 1,485,200
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-3,024,700- shares of Common Stock (includes 1,485,200
shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-3,024,700- shares of Common Stock (includes 1,485,200 shares of Common
Stock issuable upon conversion of Preferred Stock and 1,287,000 shares of
Common Stock issuable upon exercise of Warrants)
------------------------------------------------------------------------------
12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
------------------------------------------------------------------------------
13. Percent of Class Represented by Amount in Row (11)
27.0%
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14. Type of Reporting Person
IN
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6
<PAGE>
------------------------- SCHEDULE 13D --------------------
CUSIP No. 09066H104 Page 7 of 12 Pages
------------------------- --------------------
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1. Name of Reporting Person
Richard D. Paterson
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2. Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [X]
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3. SEC Use Only
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4. Source of Funds
PF, AF
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5. Check Box if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e) [_]
------------------------------------------------------------------------------
6. Citizenship or Place of Organization
Canada
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7. Sole Voting Power
-0- shares of Common Stock
-----------------------------------------------------------
NUMBER OF 8. Shared Voting Power
SHARES
-3,024,700- shares of Common Stock (includes 1,485,200
BENEFICIALLY shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
OWNED BY issuable upon exercise of Warrants)
-----------------------------------------------------------
EACH 9. Sole Dispositive Power
REPORTING
-0- shares of Common Stock
PERSON -----------------------------------------------------------
10. Shared Dispositive Power
WITH
-3,024,700- shares of Common Stock (includes 1,485,200
shares of Common Stock issuable upon conversion of
Preferred Stock and 1,287,000 shares of Common Stock
issuable upon exercise of Warrants)
------------------------------------------------------------------------------
11. Aggregate Amount Beneficially Owned by Each Reporting Person
-3,024,700- shares of Common Stock (includes 1,485,200 shares of Common
Stock issuable upon conversion of Preferred Stock and 1,287,000 shares of
Common Stock issuable upon exercise of Warrants)
------------------------------------------------------------------------------
12. Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares
[_]
------------------------------------------------------------------------------
13. Percent of Class Represented by Amount in Row (11)
27.0%
------------------------------------------------------------------------------
14. Type of Reporting Person
IN
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7
<PAGE>
This Amendment No. 3 to Schedule 13D ("Amendment No. 3") amends the
Schedule 13D filed with the Securities and Exchange Commission (the
"Commission") on January 20, 2000, as amended (collectively, the "Schedule 13D")
by the undersigned Reporting Persons relating to shares of common stock, par
value $0.001 per share (the "Common Stock"), of BioSource International, Inc., a
Delaware corporation ("BioSource" or the "Company"). Unless otherwise
indicated, all capitalized terms used herein but not defined herein shall have
the same meanings as set forth in the Schedule 13D.
Item 3. Source and Amount of Funds or Other Consideration.
-------------------------------------------------
From June 9 through June 13, 2000, Genstar Capital Partners and
Stargen acquired 51,502 shares of Common Stock and 998 shares of Common Stock,
respectively, through open market purchases on the Nasdaq National Market for an
aggregate purchase price, including payment of commissions, of $360,973 and
$6,995, respectively. Such shares were paid for by capital contributions from
the partners of Genstar Capital Partners and the members of Stargen,
respectively.
Item 4. Purpose of the Transaction.
--------------------------
Item 4 to the Schedule 13D is hereby amended to add the following
information:
On August 2, 2000, BioSource, Genstar Capital and Russell D. Hays
entered into a letter agreement (the "Letter Agreement"). Pursuant to the
Letter Agreement, Genstar Capital has agreed that Genstar Capital Partners and
its affiliates would invest up to $4.5 million in BioSource on the terms and
subject to the conditions set forth in the Letter Agreement. A copy of the
Letter Agreement is attached hereto as Exhibit 3 and is incorporated by
reference herein.
Item 5. Interest in Securities of the Issuer.
------------------------------------
Item 5 to the Schedule 13D is hereby amended to add the following
information:
(a) and (b). As a result of the purchase of the shares described
below under Item 5(c), Genstar Capital Partners beneficially owns 2,967,220
shares of Common Stock, which represents 26.6% of the Common Stock outstanding
(assuming conversion of the Shares held by Genstar Capital Partners and exercise
of the Warrants held by Genstar Capital Partners). As a result of the purchase
of the shares described below under Item 5(c), Stargen beneficially owns 57,480
shares of Common Stock, which represents 0.7% of the Common Stock outstanding
(assuming conversion of the Shares held by Stargen and exercise of the Warrants
held by Stargen). As a result of the purchase of the shares described below
under Item 5(c), the Reporting Persons beneficially own 3,024,700 shares of
Common Stock, which represents 27.0% of the Common Stock outstanding (assuming
conversion of the Shares held by Genstar Capital Partners and Stargen and
exercise of the Warrants held by Genstar Capital Partners and Stargen).
8
<PAGE>
Genstar Capital Partners has the sole power to dispose or direct the
disposition of the Shares, Warrants and shares of Common Stock which it holds
directly or the shares of Common Stock issued upon conversion of such Shares or
exercise of such Warrants. Genstar Capital Partners has the power to vote or
direct the vote of such Shares on an as-converted basis, but does not have the
power to vote or direct the vote of any of the shares of Common Stock which it
would own upon exercise of such Warrants prior to the receipt of such shares of
Common Stock upon exercise of such Warrants. Genstar Capital Partners has the
power to vote or direct the vote of the shares of Common Stock which it holds
directly.
Genstar Capital is the sole general partner of Genstar Capital
Partners and in such capacity may be deemed to have the power to dispose or
direct the disposition of the Shares, Warrants and shares of Common Stock held
by Genstar Capital Partners, and shares of Common Stock which Genstar Capital
Partners would hold upon conversion of such Shares or exercise of such Warrants,
and to vote or direct the vote of such Shares on an as-converted basis or such
shares of Common Stock.
Stargen has the sole power to dispose or direct the disposition of the
Shares, Warrants and shares of Common Stock which it holds directly and the
shares of Common Stock issued upon conversion of such Shares or exercise of such
Warrants. Stargen has the power to vote or direct the vote of such Shares on an
as-converted basis, but does not have the power to vote or direct the vote of
any of the shares of Common Stock which it would own upon exercise of such
Warrants prior to the receipt of such shares of Common Stock upon exercise of
such Warrants. Stargen has the power to vote or direct the vote of the shares
of Common Stock which it holds directly.
Messrs. Conte, Hoskins and Paterson are the managers and managing
directors of Genstar Capital and are members of Stargen, and Mr. Paterson is the
Administrative Member of Stargen, and in such capacity may be deemed to have the
power to dispose or direct the disposition of the Shares, Warrants and shares of
Common Stock held by the Investors, and shares of Common Stock which the
Investors would own upon conversion of such Shares and exercise of such
Warrants, and may be deemed to have the power to vote or direct the vote of such
Shares on an as-converted basis or such shares of Common Stock.
The Reporting Persons may be deemed to be acting as a group in
relation to their respective holdings in BioSource, but do not affirm the
existence of any such group.
Except as set forth in this Item 5(a)-(b), each of the persons named
in this Item 5(a)-(b) disclaims beneficial ownership of any Common Stock owned
beneficially or of record by any other person named in this Item 5(a)-(b).
(c) Set forth below is a schedule of all transactions in the Common
Stock by or for the account of the Reporting Persons that were effected since
May 25, 2000, the last day on which a transaction in the Common Stock by the
Reporting Persons was reported on the Schedule 13D.
9
<PAGE>
<TABLE>
<CAPTION>
Number of Shares of
-------------------
Date of Transaction Purchaser Common Stock Purchased Price per Share*
------------------- --------- ---------------------- ----------------
<S> <C> <C> <C>
June 9, 2000 Genstar Capital Partners 19,620 $7.00
June 9, 2000 Stargen 380 $7.00
June 12, 2000 Genstar Capital Partners 26,977 $7.02
June 12, 2000 Stargen 523 $7.02
June 13, 2000 Genstar Capital Partners 4,905 $7.00
June 13, 2000 Stargen 95 $7.00
</TABLE>
* Excluding commissions.
Item 6. Contracts, Arrangements, Understandings or Relationships With Respect
---------------------------------------------------------------------
to Securities of the Issuer.
---------------------------
Item 6 to the Schedule 13D is hereby amended to add the following
information:
On August 2, 2000, BioSource, Genstar Capital and Russell D. Hays
entered into a letter agreement (the "Letter Agreement"). Pursuant to the
Letter Agreement, Genstar Capital has agreed that Genstar Capital Partners and
its affiliates would invest up to $4.5 million in BioSource on the terms and
subject to the conditions set forth in the Letter Agreement. A copy of the
Letter Agreement is attached hereto as Exhibit 3 and is incorporated by
reference herein.
Item 7. Material to be Filed as Exhibits.
--------------------------------
Exhibit 1 Joint Filing Agreement (incorporated by reference to the
Schedule 13D).
Exhibit 2 Power of Attorney (incorporated by reference to the
Schedule 13D).
Exhibit 3 Letter Agreement among BioSource, Genstar Capital and
Russell D. Hays, dated as of August 2, 2000.
10
<PAGE>
SIGNATURE
---------
After reasonable inquiry and to the best of each of the undersigned's
knowledge and belief, each of the undersigned certifies that the information set
forth in this statement is true, complete and correct.
Dated: September 7, 2000
GENSTAR CAPITAL LLC
By: /s/ Jean-Pierre L. Conte
-------------------------
Name: Jean-Pierre L. Conte
Its: Managing Member
GENSTAR CAPITAL PARTNERS II, L.P.
By: Genstar Capital LLC, its general partner
By: /s/ Jean-Pierre L. Conte
-------------------------
Name: Jean-Pierre L. Conte
Its: Managing Member
STARGEN II LLC
By: /s/ Jean-Pierre L. Conte
-------------------------
Name: Jean-Pierre L. Conte
Its: Member
/s/ Jean-Pierre L. Conte
--------------------------
Jean-Pierre L. Conte
/s/ Jean-Pierre L. Conte
--------------------------
Jean-Pierre L. Conte
Attorney-in-fact for
Richard F. Hoskins
/s/ Jean-Pierre L. Conte
--------------------------
Jean-Pierre L. Conte
Attorney-in-fact for
Richard D. Paterson
<PAGE>
EXHIBIT INDEX
-------------
Exhibit 1 Joint Filing Agreement (incorporated by reference
to the Schedule 13D).
Exhibit 2 Power of Attorney (incorporated by reference to the
Schedule 13D)
Exhibit 3 Letter Agreement among BioSource, Genstar Capital and
Russell D. Hays, dated as of August 2, 2000.
12
