<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, $.01 par value
(Title of Class of Securities)
0001259461
(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 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 2 OF 9 PAGES
- ----------------------- ---------------------
- ------------------------------------------------------------------------------
NAME OF REPORTING PERSON
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
ABS MB (CN) Limited Partnership
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [ ]
(b) [ ]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
Maryland
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0 shares
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0 shares
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0 shares
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0 shares
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
0 shares
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
10 CERTAIN SHARES* [ ]
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
PN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 2 of 9 pages
<PAGE>
Page 2 of 9 pages
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 3 OF 9 PAGES
- ----------------------- ---------------------
- ------------------------------------------------------------------------------
NAME OF REPORTING PERSON
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
ABS MB Ltd.
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [ ]
(b) [ ]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
Maryland
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0 shares
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0 shares
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0 shares
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0 shares
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
0 shares
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
10 CERTAIN SHARES* [ ]
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
PN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 3 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 4 OF 9 PAGES
- ----------------------- ---------------------
- ------------------------------------------------------------------------------
NAME OF REPORTING PERSON
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Alex. Brown Investments Incorporated
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [ ]
(b) [ ]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
Maryland
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0 shares
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0 shares
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0 shares
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0 shares
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
0 shares
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
10 CERTAIN SHARES* [ ]
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
CO
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 4 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 5 OF 9 PAGES
- ----------------------- ---------------------
Item 1(a). Name of Issuer: CN Biosciences, Inc.
--------------
Item 1(b). Address of Issuer's Principal Executive Offices: 10394 Pacific
-----------------------------------------------
Center Court, San Diego, CA 92121
Item 2(a) Item 2(b) Item 2(c)
- --------- --------- ---------
Citizenship or Place
Name of Person Filing Address of Organization
- --------------------- ------- ---------------
ABS MB (CN) Limited Partnership 1 South Street Maryland
("ABS MB"), a Maryland Baltimore, MD 21202
limited partnership
ABS MB Ltd. ("ABS Ltd."), a 1 South Street Maryland
Maryland corporation and Baltimore, MD 21202
the sole general partner of
ABS MB
Alex. Brown Investments 1 South Street Maryland
Incorporated, ("Alex. Brown"), Baltimore, MD 21202
a Maryland corporation and the
sole stockholder of ABS Ltd.
Item 2(d). Title of Class of Securities: Common Stock, $.01 par value per
----------------------------
share.
Item 2(e). CUSIP Number: 0001259461
-------------
Item 3. If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b),
-------------------------------------------------------------------
check whether the person filing is a:
------------------------------------
(a) [ ] Broker or Dealer registered under Section 15 of the
Securities Exchange Act of 1934 (the "Act").
(b) [ ] Bank as defined in Section 3(a)(6) of the Act.
(c) [ ] Insurance Company as defined in Section 3(a)(19) of
the Act.
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 5 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 6 OF 9 PAGES
- ----------------------- ---------------------
(d) [ ] Investment Company registered under Section 8 of the
Investment Company Act of 1940.
(e) [ ] Investment Adviser registered under Section 203 of
the Investment Advisers Act of 1940.
(f) [ ] Employee Benefit Plan, Pension Fund which is subject
to the provisions of the Employee Retirement Income
Security Act of 1974 or Endowment Fund; see Rule 13d-
1(b)(1)(ii)(F) of the Act.
(g) [ ] Parent Holding Company, in accordance with Rule 13d-
1(b)(ii)(G) of the Act.
(h) [ ] Group, in accordance with Rule 13d-1(b)(1)(ii)(H) of
the Act.
None of the above.
Item 4. Ownership.
---------
Not applicable.
Item 5. Ownership of Five Percent or Less of a Class.
--------------------------------------------
If this statement is being filed to report the fact that as of the
date hereof the reporting person has ceased to be the beneficial
owner of more than five percent of the class of securities, check
the following [X].
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.
---------------------------------------------------------
ABS MB, ABS Ltd. and Alex. Brown expressly disclaim membership in a
"group" as defined in Rule 13d-1(b)(ii)(H).
Item 9. Notice of Dissolution of Group.
------------------------------
Not applicable.
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 6 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 7 OF 9 PAGES
- ----------------------- ---------------------
Item 10. Certification.
-------------
Not applicable. This statement on Schedule 13G is not filed pursuant
to Rule 13d-1(b).
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 7 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 8 OF 9 PAGES
- ----------------------- ---------------------
SIGNATURE
---------
After reasonable inquiry and to the best of his or its knowledge and
belief, each of the undersigned certifies that the information set forth in this
statement is true, complete and correct. We also hereby agree to file this
statement jointly pursuant to the Agreement listed on Exhibit 1 hereto.
---------
Dated: May 9, 1997
ABS MB (CN) LIMITED PARTNERSHIP
By: ABS MB Ltd.
By: /s/ Mayo A. Shattuck, III
--------------------------------
Title: President
ABS MB LTD.
By: /s/ Mayo A. Shattuck, III
-------------------------------
Title: President
ALEX. BROWN INVESTMENTS INCORPORATED
By: /s/ Mayo A. Shattuck, III
-------------------------------
Title: President
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 8 of 9 pages
<PAGE>
- ----------------------- ---------------------
CUSIP NO. 0001259461 13G PAGE 9 OF 9 PAGES
- ----------------------- ---------------------
Exhibit 1
---------
AGREEMENT
---------
Pursuant to Rule 13d-1(f)(1) under the Securities Exchange Act of 1934,
the undersigned hereby agree that only one statement containing the information
required by Schedule 13G need be filed on behalf of all of the undersigned with
respect to the ownership of shares of Common Stock of CN Biosciences, Inc. by
ABS MB (CN) Limited Partnership.
This agreement may be executed in any number of counterparts, each of
which shall be deemed an original.
EXECUTED as a sealed instrument this 9th day of May, 1997.
ABS MB (CN) LIMITED PARTNERSHIP
By: ABS MB Ltd.
By: /s/ Mayo A. Shattuck, III
-------------------------------
Title: President
ABS MB LTD.
By: /s/ Mayo A. Shattuck, III
-------------------------------
Title: President
ALEX. BROWN INVESTMENTS INCORPORATED
By: /s/ Mayo A. Shattuck, III
-------------------------------
Title: President
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 9 of 9 pages
