<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 1)*
CN Biosciences, Inc.
--------------------
(Name of Issuer)
Common Stock, par value $0.01 per share
---------------------------------------
(Title of Class of Securities)
125946 10 3
-----------
(CUSIP Number)
December 31, 1998
-----------------
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule
pursuant to which this Schedule is filed:
[ ] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*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 on 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 8 Pages
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- --------------------- -----------------
CUSIP No. 125946 10 3 13G Page 2 of 8 Pages
- --------------------- -----------------
- ---------- ---------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Warburg, Pincus Investors, L.P.
- ---------- ---------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [ ]
(b) [X]
- ---------- ---------------------------------------------------------------------
3 SEC USE ONLY
- ---------- ---------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- -------------------- ------ ----------------------------------------------------
5 SOLE VOTING POWER
-0-
------ ----------------------------------------------------
NUMBER OF 6 SHARED VOTING POWER
SHARES
BENEFICIALLY -0-
OWNED BY
------ ----------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING
PERSON -0-
WITH
------ ----------------------------------------------------
8 SHARED DISPOSITIVE POWER
-0-
- ---------- ---------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
-0-
- ---------- ---------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[ ]
- ---------- ---------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
0%
- ---------- ---------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- ---------- ---------------------------------------------------------------------
*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
- --------------------- -----------------
CUSIP No. 125946 10 3 13G Page 3 of 8 Pages
- --------------------- -----------------
- ---------- ---------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Warburg, Pincus & Co.
- ---------- ---------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [ ]
(b) [X]
- ---------- ---------------------------------------------------------------------
3 SEC USE ONLY
- ---------- ---------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
New York
- -------------------- ------ ----------------------------------------------------
5 SOLE VOTING POWER
-0-
------ ----------------------------------------------------
NUMBER OF 6 SHARED VOTING POWER
SHARES
BENEFICIALLY -0-
OWNED BY
------ ----------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING
PERSON -0-
WITH
------ ----------------------------------------------------
8 SHARED DISPOSITIVE POWER
-0-
- ---------- ---------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
-0-
- ---------- ---------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[ ]
- ---------- ---------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
0%
- ---------- ---------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- ---------- ---------------------------------------------------------------------
*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
- --------------------- -----------------
CUSIP No. 125946 10 3 13G Page 4 of 8 Pages
- --------------------- -----------------
- ---------- ---------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
E.M. Warburg, Pincus & Co., LLC
- ---------- ---------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [ ]
(b) [X]
- ---------- ---------------------------------------------------------------------
3 SEC USE ONLY
- ---------- ---------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
New York
- -------------------- ------ ----------------------------------------------------
5 SOLE VOTING POWER
-0-
------ ----------------------------------------------------
NUMBER OF 6 SHARED VOTING POWER
SHARES
BENEFICIALLY -0-
OWNED BY
------ ----------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING
PERSON -0-
WITH
------ ----------------------------------------------------
8 SHARED DISPOSITIVE POWER
-0-
- ---------- ---------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
-0-
- ---------- ---------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- ---------- ---------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
0%
- ---------- ---------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
OO
- ---------- ---------------------------------------------------------------------
*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
Item 1(a). Name of Issuer:
- ---------- ---------------
CN Biosciences, Inc. (the "Issuer")
Item 1(b). Address of Issuer's Principal Executive Offices:
- ---------- ------------------------------------------------
10394 Pacific Center Court
San Diego, California 92121
Items 2(a) Name of Person Filing; Address of Principal
- ---------- -------------------------------------------
and (b). Business Office:
- -------- ----------------
This statement is filed by and on behalf of
(a) Warburg, Pincus Investors, L.P., a
Delaware limited partnership ("WPI"); (b)
Warburg, Pincus & Co., a New York general
partnership ("WP"); and (c) E.M. Warburg,
Pincus & Co., LLC, a New York limited
liability company ("EMW LLC"), which manages
WPI. WP, as the sole general partner of WPI,
has a 20% interest in the profits of WPI.
Lionel I. Pincus is the managing partner of
WP and the managing member of EMW LLC and may
be deemed to control both WP and EMW LLC. The
members of EMW LLC are substantially the same
as the partners of WP. The business address
of each of the foregoing is 466 Lexington
Avenue, New York, New York 10017.
WPI, WP and EMW LLC are collectively referred
to herein as the "Reporting Persons".
Item 2(c). Citizenship:
- ---------- ------------
Not Applicable
Item 2(d). Title of Class of Securities:
- ---------- -----------------------------
Common Stock, par value $0.01 per share (the "Common Stock")
Item 2(e). CUSIP Number:
- ---------- -------------
125946 10 3
Item 3. If this statement is filed pursuant to
- ------- --------------------------------------
ss.ss. 240.13d-1(b) or 240.13d-2(b) or (c),
-------------------------------------------
check whether the person filing is a:
-------------------------------------
(a)[ ] Broker or dealer registered under section 15 of the Act
(15 U.S.C. 78o).
(b)[ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C.
78c).
Page 5 of 8 Pages
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(c)[ ] Insurance company as defined in section 3(a)(19) of the
Act (15 U.S.C. 78c).
(d)[ ] Investment company registered under section 8 of the
Investment Company Act of 1940 (15 U.S.C. 80a-8).
(e)[ ] An investment adviser in accordance with ss.
240.13d-1(b)(1)(ii)(E).
(f)[ ] An employee benefit plan or endowment fund in accordance
with ss. 240.13d-1(b)(1)(ii)(F).
(g)[ ] A parent holding company or control person in accordance
with ss. 240.13d-1(b)(1)(ii)(G).
(h)[ ] A savings association as defined in Section 3(b) of the
Federal Deposit Insurance Act (12 U.S.C. 1813).
(i)[ ] A church plan that is excluded from the definition of an
investment company under section 3(c)(14) of the
Investment Company Act of 1940 (15 U.S.C. 80a-3).
(j)[ ] Group, in accordance with ss. 240.13d-1(b)(1)(ii)(J).
Not Applicable
Item 4. Ownership:
- ------- ----------
Warburg, Pincus Investors, L.P.
-------------------------------
(a) Amount beneficially owned: -0- shares of Common Stock, as of
December 31, 1998.
(b) Percent of Class: 0%
(c) (i) Sole power to vote or to direct the vote: -0-
(ii) Shared power to vote or to direct the vote: -0-
(iii) Sole power to dispose or to direct the disposition
of: -0-
(iv) Shared power to dispose or direct the disposition
of: -0-
Warburg, Pincus & Co.
---------------------
(a) Amount beneficially owned: -0- shares of Common Stock, as of
December 31, 1998.
(b) Percent of Class: 0%
(c) (i) Sole power to vote or to direct the vote: -0-
(ii) Shared power to vote or to direct the vote: -0-
Page 6 of 8 Pages
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(iii) Sole power to dispose or to direct the disposition
of: -0-
(iv) Shared power to dispose or to direct the disposition
of: -0-
E.M. Warburg, Pincus & Co., LLC
-------------------------------
(a) Amount beneficially owned: -0- shares of Common Stock, as of
December 31, 1998.
(b) Percent of Class: 0%
(c) (i) Sole power to vote or to direct the vote: -0-
(ii) Shared power to vote or direct the vote: -0-
(iii) Sole power to dispose or to direct the disposition
of: -0-
(iv) Shared power to dispose or to direct the disposition
of: -0-
Item 5. Ownership of Five Percent or Less of a Class:
- ------- ---------------------------------------------
[X] As of December 23, 1998, the Reporting Persons ceased to be
the beneficial owner of more than five percent of the Common
Stock.
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
Page 7 of 8 Pages
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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 statement is true, complete and
correct.
Dated: February 11, 1999
WARBURG, PINCUS INVESTORS, L.P.
By: Warburg, Pincus & Co., its General
Partner
By: /s/ Stephen Distler
-----------------------------
Stephen Distler, Partner
WARBURG, PINCUS & CO.
By: /s/ Stephen Distler
-----------------------------
Stephen Distler, Partner
E.M. WARBURG, PINCUS & CO., LLC
By: /s/ Stephen Distler
-----------------------------
Stephen Distler, Member
Page 8 of 8 Pages
