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                                                                 EXHIBIT 10.009

                          AGREEMENT TO TERMINATE LEASE


This Agreement to Terminate Lease (the "Agreement") is made as of November 6,
2000, by and between AMB PROPERTY, L.P., a Delaware limited partnership
("Lessor"), and CYGNUS, INC., a Delaware corporation ("Lessee"), with reference
to the following facts.


                                    RECITALS

         WHEREAS, Lincoln Menlo Associates Limited, a California limited
partnership ("Lincoln") Lessor and Lessee, have entered into that certain Lease
Agreement dated October 15, 1991, and that certain First Amendment dated June
30, 1994, and that certain Second Amendment dated August 25, 1995, and that
certain Third Amendment dated August 23, 1996, and that certain Fourth Amendment
dated July 20, 1999 (collectively, "the Lease"), whereby Lincoln leased to
Lessee and Lessee leased from Lincoln approximately 22,237 rentable square feet
in those certain premises located at 1255 Hamilton Court, Menlo Park, California
94025 (the "Premises");

         WHEREAS, Lincoln has assigned its interest in the Lease to Lessor;

         WHEREAS, pursuant to the Lease, the Lease Term for the Premises would
end on October 31, 2001;


         NOW THEREFORE, in consideration of the mutual promises and covenants
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

         1. RECITALS. Lessor and Lessee hereby agree that the recitals set forth
hereinabove are true and correct and incorporated into this Agreement.

         2. LEASE TERMINATION. Lessor and Lessee hereby agree to terminate the
Lease as of November 30, 2000 (the "Termination Date"). On or before the
Termination Date, Lessee shall vacate and surrender possession of the Premises
to Lessor in accordance with the provisions of the Lease.

                  Lessor and Lessee hereby acknowledge and agree that Lessor has
applied Lessee's security deposit in the amount of Seventeen Thousand Seven
Hundred Ninety and 00/100 Dollars ($17,790.00) to the last month's base rent.

         Upon termination of the Lease, the vacation and surrender of the
Premises by Lessee, and completion of the Termination Conditions (defined in
Paragraph 3 below) of this Agreement, Lessor and Lessee shall have no further
rights, obligations or claims with respect to each other arising from this
Agreement or the Lease, except for those obligations of Lessee under the Lease
which are expressly required to survive and continue after the termination or
expiration of the Lease. Lessee and Lessor hereby acknowledge and agree that
certain obligations of Lessee survive the termination or expiration of the
Lease, pursuant to the terms and provisions of the Lease, and the parties
further agree that it is the intention of Lessee and Lessor that this Agreement
not affect such ongoing obligations of Lessee.

         3. TERMINATION CONDITIONS. The following conditions shall be conditions
to the termination of the Lease (collectively, the "Termination Conditions"):

                  A. PERFORMANCE BY LESSEE. Performance by Lessee through the
Termination Date of all obligations required to be performed by Lessee under the
Lease, as and when such obligations are required to be performed under the
Lease, including, without limitation, the payment of Rent, Additional Rent and
any other sums required to be paid by Lessee to Lessor. Upon execution of this
document, Lessee shall pay all obligations through November 30, 2000. Lessee
shall not be responsible for replacement or repairs of carpet or for repainting
the Premises.

                  B. SURRENDER OF THE PREMISES. Lessee's vacating the Premises
and Lessee's surrender of the Premises to Lessor in accordance with the
provisions of the Lease by the Termination Date, including, without limitation,
the removal by Lessee of all of its personal property and to the extent required
by Lessor, the removal of any fixtures or improvements to the Premises, and the
repair and restoration of the Premises to the satisfaction of Lessor.

                  The Termination Conditions are conditions for the sole benefit
of Lessor and may, at the sole discretion of Lessor, be waived by Lessor. If any
or all of the Termination Conditions are not satisfied as required, then Lessor
may terminate this Agreement and reinstate the Lease (in which event the Lease
shall remain in full force and effect) or Lessor may consider the Lease
terminated as of the Termination Date; provided, in either instance, Lessee
shall immediately pay to Lessor any and all damages arising from such failure by
Lessee, including without limitation, all costs and expenses incurred by Lessor
in connection with the leasing of the Premises to any new lessee (hereafter
defined) (including, without limitation, all costs related to the planning and
installation of any lessee improvements contemplated for the new lessee in the
Premises), consequential and punitive damages, regardless of the speculative
nature of such damages, subject to Paragraph 3A above.

         4. ABANDONED PROPERTY. In addition to any rights Lessor may have under
the Lease or this Agreement, Lessor, at its sole option, may deem any furniture,
fixtures, shelving, cabinets, tables, equipment, lighting, and other fixtures or
personal property in, on or attached to the Premises and remaining in or on the
Premises after the Termination Date (the "Abandoned Property"), whether or not
belonging to Lessee, to be abandoned, and Lessor may dispose of the Abandoned
Property as it in its sole discretion deems appropriate. Lessee shall not be
entitled to any proceeds received by Lessor as a result of the disposition of
the Abandoned Property. Lessee waives, to the greatest extent permitted by law,
all of its rights under California Civil Code Sections 1980, et. seq, as the
same may be amended from time to time, and any related and successor statutes
thereto.

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         5. LESSEE'S REPRESENTATIONS AND WARRANTIES. Lessee hereby represents
and warrants to Lessor the following, each of which shall survive the
termination of the Lease, the vacation and surrender of the Premises, the
surrender of the Lease and Lessee's leasehold estate, and the termination of
this Agreement:

                  A. Lessee has not made any assignment, sublease, transfer,
conveyance or other disposition of the Lease, Lessee's leasehold estate, the
Premises, any other rights, title, interest under or arising by virtue of the
Lease, or of any claim, demand, obligation, liability, action or cause of action
arising from or pursuant to the Lease or arising from any rights of possession
arising under or by virtue of the Lease, Lessee's leasehold estate, or the
Premises.

                  B. The person or entity executing this Agreement on behalf of
Lessee has the full right and authority to execute this Agreement on behalf of
said party and to bind said party without the consent or approval of any other
person or entity.

                  C. Lessee has the full power, capacity, authority and legal
right to execute and deliver this Agreement.

                  D. This Agreement is legal, valid and binding upon Lessee and
Lessor, and this Agreement is enforceable in accordance with its terms.

                  E. Lessee has not (i) made a general assignment for the
benefit of creditors, (ii) filed any voluntary petition in bankruptcy or
suffered the filing of an involuntary petition by its creditors, (iii) suffered
the appointment of a receiver to take possession of all, or substantially, all
of its assets, (iv) suffered the attachment or other judicial seizure of all, or
substantially all, of its assets, (v) admitted in writing to its inability to
pay its debts as they become due, or (vi) made an offer of settlement, extension
or composition to its creditors generally.

         6. All capitalized terms used herein and not otherwise defined herein
shall have the same meaning ascribed to such terms as set forth in the Lease.

         7. General Provisions.

                  A. Time is of the essence in the performance of the parties'
respective obligations set forth in this Agreement.

                  B. Notices shall be deemed given when received or when receipt
is refused. Notices shall be sent by U.S. mail, registered or certified, return
receipt requested, postage prepaid or by overnight delivery service showing
receipt of delivery. If to Lessee, notices shall be sent to: Cygnus, Inc., 400
Penobscot Drive, Redwood City, California 94063, and if to Lessor: to Legacy
Partners Commercial, Inc., 933 Hamilton Avenue, Menlo Park, California 94025;
Attention: Sheryn Cockett. If at any time either party should change its
address, such party shall deliver, written notice thereof to the other party
together with the designation of the new address.

                  C. This Agreement constitutes the entire understanding of the
parties and all prior agreements, representations, and understandings between
the parties, whether oral or written, are deemed null, all of the foregoing
having been merged into this Agreement. The parties acknowledge that each party
and/or its counsel have reviewed and revised this Agreement and that no rule of
construction to the effect that any ambiguities are to be resolved against the
drafting party shall be employed in the interpretation of this Agreement or any
amendments or exhibits to this Agreement or any document executed and delivered
by either party in connection with this Agreement.

                  D. Lessee may not assign its rights, obligations and interest
in this Agreement to any other person or entity, without Lessor's written
consent thereto. Any attempted assignment shall be null and void. This Agreement
shall inure to the benefit of and be binding upon the parties to this Agreement
and their respective successors and assigns.

                  E. If for any reason, any provision of this Agreement shall be
held to be unenforceable, it shall not affect the validity or enforceability of
any other provision of this Agreement.

                  F. This Agreement shall be governed by and construed under the
laws of the State of California.

                  G. Any and all addenda attached hereto and either signed or
initialed by the parties shall be deemed a part hereof. This Agreement,
including addenda, if any, expresses the entire agreement of the parties and
supersedes any and all previous agreements between the parties with regard to
the Premises and the Lease. There are no other understandings, oral or written,
which in any way alter or enlarge its terms, and there are no warranties or
representations of any nature whatsoever, either expressed or implied, except as
may be set forth herein. Any and all future modifications of this Agreement will
be effective only if they are in writing and signed by the parties hereto. The
terms and conditions of any and all addenda attached hereto and any and all
future modifications of this Agreement shall supersede and replace any
inconsistent provisions in this Agreement.

                  H. This Agreement may be executed in counterparts. All
executed counterparts shall constitute one agreement, and each counterpart shall
be deemed an original.

                  I. In the event any dispute between the parties results in
litigation or other proceeding, the prevailing party shall be reimbursed by the
nonprevailing party for all reasonable costs and expenses, including, without
limitation, reasonable attorneys' and experts' fees and costs incurred by the
prevailing party in connection with such litigation or other proceeding and any
appeal thereof. Such costs, expenses and fees shall be included in and made a
part of the judgment recovered by the prevailing party, if any.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date and year first written above in this Agreement.

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LESSEE:

CYGNUS, INC.,
a Delaware Corporation

By:               /s/ CRAIG W. CARLSON
         --------------------------------------------

Its:              SR. VP, FINANCE & CFO
         --------------------------------------------

Date:             11/27/00
         --------------------------------------------

By:               /s/ BARBARA G. MCCLUNG
         --------------------------------------------

Its:              SR. VP & GENERAL COUNSEL & SECRETARY
         ---------------------------------------------

Date:             11/27/00
         --------------------------------------------

LESSOR:

AMB PROPERTY, L.P.,
a Delaware limited partnership

By:      AMB PROPERTY CORPORATION,
         a Maryland corporation, its general partner

         By:               /s/ GAYLE STARR
                  -----------------------------------
                  Gayle Starr

         Its:     Vice President

Date:             12/7/00
         --------------------------------------------


If Lessee is a CORPORATION, the authorized officers must sign on behalf of the
corporation and indicate the capacity in which they are signing. The Lease must
be executed by the president or vice-president AND the secretary or assistant
secretary, UNLESS the bylaws or a resolution of the board of directors shall
otherwise provide, in which event, the bylaws or a certified copy of the
resolution, as the case may be, must be attached to this Lease.


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