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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
_______________________
SCHEDULE 13G
(Rule 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO RULES 13d-1(b), (c) and (d) AND AMENDMENTS THERETO
FILED PURSUANT TO 13d-2
(Amendment No. ________________)/1/
Maxygen, Inc.
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(Name of Issuer)
Common Stock, par value $.0001 per share
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(Title of Class of Securities)
577776107
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(CUSIP Number)
December 31, 1999
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(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)
[X] Rule 13d-1(d)
____________________
/1/ 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 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).
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Schedule 13G Forms
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CUSIP No. 577776107 13G Page 2 of 11 Pages
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1. NAME OF REPORTING PERSON
IRS IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Technogen Associates, L.P.
77-0466323
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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. CITIZENSHIP OR PLACE OF ORGANIZATION
California
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Number of Shares 5. SOLE VOTING POWER Nil
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Beneficially Owned By 6. SHARED VOTING POWER 3,211,574
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Each Reporting Person 7. SOLE DISPOSITIVE POWER Nil
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With 8. SHARED DISPOSITIVE POWER 3,211,574
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
3,211,574
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[_]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
10.4%
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12. TYPE OF REPORTING PERSON*
PN
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Schedule 13G Forms
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CUSIP No. 577776107 13G Page 3 of 11 Pages
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1. NAME OF REPORTING PERSONS
IRS IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Technogen Enterprises, L.L.C.
77-0469459
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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. CITIZENSHIP OR PLACE OF ORGANIZATION
California
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Number of Shares 5. SOLE VOTING POWER Nil
-------------------------------------------------------
Beneficially Owned By 6. SHARED VOTING POWER 63,198
-------------------------------------------------------
Each Reporting Person 7. SOLE DISPOSITIVE POWER Nil
-------------------------------------------------------
With 8. SHARED DISPOSITIVE POWER 63,198
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
63,198
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[_]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
Less than 1%
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12. TYPE OF REPORTING PERSON*
00
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
Schedule 13G Forms
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CUSIP No. 577776107 13G Page 4 of 11 Pages
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1. NAME OF REPORTING PERSONS
IRS IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Technogen Managers, L.L.C.
77-0466322
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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. CITIZENSHIP OR PLACE OF ORGANIZATION
California
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Number of Shares 5. SOLE VOTING POWER Nil
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Beneficially Owned By 6. SHARED VOTING POWER 3,211,574
--------------------------------------------------------
Each Reporting Person 7. SOLE DISPOSITIVE POWER Nil
--------------------------------------------------------
With 8. SHARED DISPOSITIVE POWER 3,211,574
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
3,211,574
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[_]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
10.4%
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12. TYPE OF REPORTING PERSON*
00
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
Schedule 13G Forms
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CUSIP No. 577776107 13G Page 5 of 11 Pages
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1. NAME OF REPORTING PERSONS
IRS IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Isaac Stein
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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. CITIZENSHIP OR PLACE OF ORGANIZATION
United States
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Number of Shares 5. SOLE VOTING POWER 617,334
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Beneficially Owned By 6. SHARED VOTING POWER 3,274,772
--------------------------------------------------------
Each Reporting Person 7. SOLE DISPOSITIVE POWER 617,334
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With 8. SHARED DISPOSITIVE POWER 3,274,772
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
3,892,106
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[_]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
12.6%
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12. TYPE OF REPORTING PERSON*
IN
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
<TABLE>
<CAPTION>
<S> <C> <C>
Schedule 13G Forms
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CUSIP No. 577776107 13G Page 6 of 11 Pages
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</TABLE>
<TABLE>
<S> <C> <C> <C>
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1. NAME OF REPORTING PERSONS
IRS IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Gordon Ringold
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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. CITIZENSHIP OR PLACE OF ORGANIZATION
United States
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Number of Shares 5. SOLE VOTING POWER 546,667
Beneficially Owned By ------------------------------------------------------------------------------------------------------
Each Reporting Person 6. SHARED VOTING POWER 3,274,772
With ------------------------------------------------------------------------------------------------------
7. SOLE DISPOSITIVE POWER 546,667
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8. SHARED DISPOSITIVE POWER 3,274,772
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
3,821,439
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[_]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
12.4%
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12. TYPE OF REPORTING PERSON*
IN
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</TABLE>
*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Schedule 13G Forms
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13G Page 7 of 11 Pages
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Item 1(a). Name of Issuer
Maxygen, Inc.
Item 1(b). Address of Issuers' Principal Executive Offices
515 Galveston Drive
Redwood City, California 94063
Item 2(a). Name of Persons Filing
I. Technogen Associates, L.P.
II. Technogen Enterprises, L.L.C.
III. Technogen Managers, L.L.C.
IV. Isaac Stein
V. Gordon Ringold
Item 2(b). Address of Principal Business Office
525 University Avenue, Suite 700
Palo Alto, California 94301
Item 2(c). Citizenship
I, II and III California
IV and V United States
Item 2(d). Title of Class of Securities
Common Stock, par value $0.0001
Item 2(e). CUSIP Number
577776107
Item 3. If this statement is filed pursuant to Rules 13d-1(b) or 13d-2(b) or
2(c), check whether the person filing is a:
N.A.
If this statement is filed pursuant to Rule 13d-1(c), check this box. [_]
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Schedule 13G Forms
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13G Page 8 of 11 Pages
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Item 4. Ownership
The following information is reported as of December 31, 1999.
The Reporting Persons disclaim membership in a group.
The aggregate number of securities and percentage of the class of
securities of the Issuer beneficially owned by each Reporting Person named in
Item 2(a), as well as the number of securities as to which such person is deemed
to have sole power to vote or to direct the vote, shared power to vote or to
direct the vote, sole power to dispose or to direct the disposition, or shared
power to dispose or direct the disposition, is set forth in the following table:
<TABLE>
<CAPTION>
Power to Vote Power to Dispose
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No of Securities
Person Beneficially Owned % of Class Sole Shared Sole Shared
- --------------------------------- ------------------ --------------- ------- --------- ------- ---------
<S> <C> <C> <C> <C> <C> <C>
Technogen Associates, L.P. 3,211,574 10.4% 0 3,211,574 0 3,211,574
Technogen Enterprises, L.L.C. 63,198 less than 1% 0 63,198 0 63,198
Technogen Managers, L.L.C. (1) 3,211,574 10.4% 0 3,211,574 0 3,211,574
Isaac Stein (2) 3,892,106 12.6% 617,334 3,274,772 617,334 3,274,772
Gordon Ringold (3) 3,821,439 12.4% 546,667 3,274,772 546,667 3,274,772
Total 4,438,773 14.4% 1,164,001 3,274,772 1,164,001 3,274,772
</TABLE>
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(1) Technogen Managers, L.L.C. is the general partner of Technogen Associates,
L.P.
(2) Includes 3,211,574 shares held by Technogen Associates, L.P. and 63,198
shares held by Technogen Enterprises, L.L.C. Technogen Managers, L.L.C. is
the general partner of Technogen Associates, L.P. Mr. Stein is a Member of
Technogen Enterprises, L.L.C. and Technogen Managers, L.L.C. and has shared
power to vote or direct the vote of and shared power to dispose or direct
the disposition of the shares held by the limited liability companies. Mr.
Stein disclaims beneficial ownership of these shares except to the extent of
his pecuniary interest in the limited liability companies. Includes 525,667
shares held by the Stein 1995 Revocable Trust, of which Mr. Stein is a
trustee and 41,667 shares held by Stein Partners, of which Mr. Stein is a
general partner.
(3) Includes 3,211,574 shares held by Technogen Associates, L.P. and 63,198
shares held by Technogen Enterprises, L.L.C. Technogen Managers, L.L.C. is
the general partner of Technogen Associates, L.P. Dr. Ringold is a Member of
Technogen Enterprises, L.L.C. and Technogen Managers, L.L.C. and has shared
power to vote or direct the vote of and shared power to dispose or direct
the disposition of the shares held by the limited liability companies. Dr.
Ringold disclaims beneficial ownership of these shares except to the extent
of his pecuniary interest in the limited liability companies. Includes
20,000 shares held by the Gregory Zarucki Ringold 1998 Trust, 20,000 shares
held by the Alexander Ringold 1998 Trust and 20,000 shares held by the
Melanie Gault-Ringold 1998 Trust.
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Schedule 13G Forms
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13G Page 9 of 11 Pages
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Item 5. Ownership of Five Percent or Less of a Class
N.A.
Item 6. Ownership of More than Five Percent on Behalf of Another Person
I, II and III N.A.
IV Beneficiaries of the Stein 1995 Revocable Trust have
the right to receive the proceeds from the sale of
525,667 shares held by such trust, in accordance with
the trust documents.
V Beneficiaries of each of the Gregory Zarucki Ringold
1998 Trust, Alexander Zarucki Ringold 1998 Trust and
Melanie Gault-Ringold 1998 Trust have the right to
receive the proceeds from the sale of 20,000 shares
held by such trust, in accordance with the trust
documents.
Item 7. Identification and Classification of the Subsidiary Which Acquired the
Security Being Reported on by the Parent Holding Company
N.A.
Item 8. Identification and Classification of Members of the Group
N.A.
Item 9. Notice of Dissolution of Group
N.A.
Item 10. Certification
N.A.
Material to be Filed as Exhibits
A. Agreement of Joint Filing
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Schedule 13G Forms
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13G Page 10 of 11 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.
February 14, 2000 TECHNOGEN ASSOCIATES, L.P.
By: TECHNOGEN MANAGERS, L.L.C.,
its general partner
By: /s/ Isaac Stein
---------------------------
Isaac Stein
Member
TECHNOGEN ENTERPRISES, L.L.C.
By: /s/ Isaac Stein
---------------------------
Isaac Stein
Member
TECHNOGEN MANAGERS, L.L.C.
By: /s/ Isaac Stein
---------------------------
Isaac Stein
Member
/s/ Isaac Stein
-------------------------------
Isaac Stein
/s/ Gordon Ringold
-------------------------------
Gordon Ringold
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Schedule 13G Forms
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13G Page 11 of 11 Pages
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EXHIBIT A
Agreement of Joint Filing
The undersigned hereby agree that a single Schedule 13G (or any amendment
thereto) relating to the Common Stock of Maxygen, Inc. shall be filed on behalf
of each of the undersigned and that this Agreement shall be filed as an exhibit
to such Schedule 13G.
February 14, 2000 TECHNOGEN ASSOCIATES, L.P.
By: TECHNOGEN MANAGERS, L.L.C.,
its general partner
By: /s/ Isaac Stein
----------------
Isaac Stein
Member
TECHNOGEN ENTERPRISES, LLC
By: /s/ Isaac Stein
----------------
Isaac Stein
Member
TECHNOGEN MANAGERS, L.L.C.
By: /s/ Isaac Stein
----------------
Isaac Stein
Member
/s/ Isaac Stein
---------------
Isaac Stein
/s/ Gordon Ringold
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Gordon Ringold
