<PAGE>
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 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 RULE 13d-2(b)
(Amendment No. 2)*
3Dfx Interactive, Inc.
- --------------------------------------------------------------------------------
(Name of Issuer)
Common Stock
- --------------------------------------------------------------------------------
(Title of Class of Securities)
88553X103
- --------------------------------------------------------------------------------
(CUSIP Number)
December 31, 1999
- --------------------------------------------------------------------------------
(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-(c)
---
X 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 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>
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CUSIP No 88553X103 13G Page 2 of 17
- --------------------- ------------------------
- ------------------------------------------------------------------------------
NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Venrock Associates
I.R.S.#13-6300995
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
New York, U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
0
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.00%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
PN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 2 of 17 pages
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CUSIP No 88553X103 13G Page 3 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Venrock Associates II, L.P.
I.R.S.#13-3844754
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
New York, U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
0
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.00%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
PN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 3 of 17 pages
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CUSIP No 88553X103 13G Page 4 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Anthony B. Evnin
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
57,030
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
57,030
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
57,030
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.23%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 4 of 17 pages
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CUSIP No 88553X103 13G Page 5 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
David R. Hathaway
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
55,405
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
55,405
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
55,405
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.23%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 5 of 17 pages
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CUSIP No 88553X103 13G Page 6 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Patrick F. Lattrell
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
52,028
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
52,028
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
52,028
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.21%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 6 of 17 pages
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CUSIP No 88553X103 13G Page 7 of 17
- --------------------- ------------------------
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Ted H. McCourtney
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
65,450
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
65,450
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
65,450
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.27%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 7 of 17 pages
<PAGE>
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CUSIP No 88553X103 13G Page 8 of 17
- --------------------- ------------------------
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Ray A. Rothrock
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
45,963
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
45,963
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
45,963
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.19%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 8 of 17 pages
<PAGE>
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CUSIP No 88553X103 13G Page 9 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Kimberley A. Rummelsburg
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
0
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 1,300
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
1,300
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
1,300
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.01%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 9 of 17 pages
<PAGE>
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CUSIP No 88553X103 13G Page 10 of 17
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Anthony Sun
###-##-####
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [x]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
U.S.A.
- ------------------------------------------------------------------------------
SOLE VOTING POWER
5
NUMBER OF
68,555
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
-----------------------------------------------------------
EACH SOLE DISPOSITIVE POWER
7
REPORTING
0
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
68,555
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
68,555
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
0.28%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IN
- ------------------------------------------------------------------------------
*SEE INSTRUCTIONS BEFORE FILLING OUT!
Page 10 of 17 pages
<PAGE>
Introduction: This Amendment No. 2 amends a Statement on Schedule 13G (the
"Schedule") filed with the Securities and Exchange Commission on February 14,
1997 on behalf of Venrock Associates, a limited partnership organized under the
laws of the State of New York, Venrock Associates II, L.P., a limited
partnership organized under the laws of the State of New York, Anthony B. Evnin,
David R. Hathaway, Patrick F. Latterell, Ted H. McCourtney, Ray A. Rothrock,
Kimberley A. Rummelsburg and Anthony Sun in respect of shares of Common Stock of
3Dfx Interactive, Inc.
Item 1(a) Name of Issuer
- -------------------------------
3Dfx Interactive, Inc.
Item 1(b) Address of Issuer's Principal Executive Offices
- ----------------------------------------------------------------
4435 Fortran Drive
San Jose, CA 95134
Item 2(a) Name of Person Filing
- --------------------------------------
Venrock Associates ("Venrock")
Venrock Associates II, L.P. ("Venrock II")
Anthony B. Evnin
David R. Hathaway
Patrick F. Latterell
Ted H. McCourtney
Ray A. Rothrock
Kimberley A. Rummelsburg
Anthony Sun
Item 2(b) Address of Principal Business Office or, if none, Residence
- ---------------------------------------------------------------------------
New York Office: Menlo Park Office:
30 Rockefeller Plaza 2494 Sand Hill Road
Room 5508 Suite 200
New York, NY 10112 Menlo Park, CA 94025
Item 2(c) Citizenship
- --------- -----------
Venrock and Venrock II are limited partnerships organized in the
State of New York. Anthony B. Evnin, David R. Hathaway, Patrick
F. Latterell, Ted H. McCourtney, Ray A. Rothrock, Kimberley A.
Rummelsburg and Anthony Sun are General Partners of Venrock and
Venrock II and all are citizens of the United States of America.
Item 2(d) Title of Class of Securities
- --------------------------------------------
Common Stock
Item 2(e) CUSIP Number
- ----------------------------
88553X103
Item 3 Not applicable.
- ------
Page 11 of 17 pages
<PAGE>
Item 4 Ownership
- -------------------------
(a) and (b)
Each of Venrock and Venrock II owns no shares or 0% of the
outstanding shares of common stock.
Anthony B. Evrin beneficially owns 57,030 shares or 0.23% of the
outstanding shares of common stock. David R. Hathaway
beneficially owns 55,405 shares or 0.23% of the outstanding
shares of common stock. Patrick F. Latterell beneficially owns
52,028 shares or 0.21% of the outstanding shares of common
stock. Ted M. McCourtney beneficially owns 65,450 shares or
0.27% of the outstanding shares of common stock. Ray A. Rothrock
beneficially owns 45,963 shares or 0.19% of the outstanding
shares of common stock. Kimberley A. Rummelsburg beneficially
owns 1,300 shares or 0.01% of the outstanding shares of common
stock. Anthony Sun beneficially owns 68,555 shares or 0.28% of
the outstanding shares of common stock.
(c)
Anthony B. Ervin has sole voting and dispositive power over
57,030 shares of common stock and shared voting and dispositive
power over no shares of common stock. David R. Hathaway has sole
voting and dispositive power over 55,405 shares of common stock
and shared voting and dispositive power over no shares of common
stock. Patrick F. Latterall has sole voting and dispositive
power over 52,028 shares of common stock and shared voting and
dispositive power over no shares of common stock. Ted M.
McCourtney has solve voting and dispostive power over 65,450
shares of common stock and shared voting and dispositive power
over no shares of common stock. Ray A. Rothrock has sole voting
and dispositve power over 45,963 shares of common stock and
shared voting and dispositive power over no shares of common
stock. Kimberley A. Rummelsburg has sole voting and dispositive
power over no shares of common stock and shared voting and
dispositive power over 1,300 shares of common stock. Anthony Sun
ha sole voting and dispositive power over 68,555 shares shares
of common stock and shared voting and dispositive power over no
shares of common stock.
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 of Behalf of Another Person
- -------------------------------------------------------------------------------
No person, other than the General Partners of Venrock and
Venrock II, has the right to receive or the power to direct the
receipt of dividends from, or the proceeds from the sale of, the
shares of common stock owned by Venrock and Venrock II.
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
- -------------------------------------------------------------------------
This schedule is being filed pursuant to Rule 13d-1(d). The
identities of the seven General Partners of Venrock and Venrock
II are stated in Item 2.
Item 9 Notice of Dissolution of Group
- ----------------------------------------------
Not applicable.
Page 12 of 17 pages
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Item 10 Certification
- --------------------------
Not applicable.
Page 13 of 17 pages
<PAGE>
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 VENROCK ASSOCIATES
By: /s/ Ted H. McCourtney
---------------------
Ted H. McCourtney
General Partner
February 14, 2000 VENROCK ASSOCIATES II, L.P.
By: /s/ Ted H. McCourtney
----------------------------
Ted H. McCourtney
General Partner
February 14, 2000 GENERAL PARTNERS
*
------------------------
Anthony B. Evnin
*
-------------------------
David R. Hathaway
*
--------------------------
Patrick F. Latterell
*
---------------------------
Ted H. McCourtney
*
----------------------------
Ray A. Rothrock
*
-----------------------------
Kimberley A. Rummelsburg
*
------------------------------
Anthony Sun
* By: /s/ Ted H. McCourtney
----------------------
Ted H. McCourtney
Attorney-in-Fact
Page 14 of 17 pages
<PAGE>
Exhibit 24.1
------------
POWER OF ATTORNEY
KNOWN ALL MEN BY THESE PRESENTS that each person whose signature appears below
constitutes and appoints Ted H. McCourtney his or her true and lawful attorney-
in-fact and agent, acting alone, with full power of substitution and
resubstitution, for him or her and in his or her name, place and stead, in any
and all capacities, to sign the Schedule 13G, and all amendments thereto, with
all exhibits thereto, and all documents in connection therewith, with respect to
the beneficial ownership by the undersigned of the equity securities of Visual
Networks, Inc., and to file the same, with the Securities and Exchange
Commission and any other person, granting unto the attorney-in-fact and agent
full power and authority to do and perform each and every act and thing
requisite and necessary to be done in and about the premises, as fully to all
intents and purposes as he or she might or could do in person, and hereby
ratifies and confirms all that said attorney-in-fact and agent or his substitute
or substitutes, may lawfully do or cause to be done.
February 9, 1999
/s/ Anthony B. Evnin
--------------------
Anthony B. Evnin
/s/ David R. Hathaway
---------------------
David R. Hathaway
/s/ Patrick F. Latterell
------------------------
Patrick F. Latterell
/s/ Ted H. McCourtney
---------------------
Ted H. McCourtney
/s/ Ray A. Rothrock
-------------------
Ray A. Rothrock
/s/ Kimberley A. Rummelsburg
----------------------------
Kimberley A. Rummelsburg
/s/ Anthony Sun
---------------
Anthony Sun
Page 15 of 16 pages
<PAGE>
Exhibit 99.1
------------
AGREEMENT
Pursuant to Rule 13d-1(k)(1) promulgated pursuant to the Securities
Exchange Act of 1934, as amended, the undersigned agree that the attached
Schedule 13G is being filed on behalf of each of the undersigned.
February 14, 2000 VENROCK ASSOCIATES
By: /s/ Ted H. McCourtney
---------------------
Ted H. McCourtney
General Partner
February 14, 2000 VENROCK ASSOCIATES II, L.P.
By: /s/ Ted H. McCourtney
---------------------
Ted H. McCourtney
General Partner
February 14, 2000 GENERAL PARTNERS
/s/ Anthony B. Evnin
--------------------
Anthony B. Evnin
/s/ David R. Hathaway
---------------------
David R. Hathaway
/s/ Patrick F. Latterell
------------------------
Patrick F. Latterell
/s/ Ted H. McCourtney
--------------------
Ted H. McCourtney
/s/ Ray A. Rothrock
------------------
Ray A. Rothrock
/s/ Kimberley A. Rummelsburg
----------------------------
Kimberley A. Rummelsburg
/s/ Anthony Sun
--------------
Anthony Sun
Page 16 of 16 pages
