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                                                                  EXHIBIT 10.513

                            INDEMNIFICATION AGREEMENT


         This Indemnification Agreement (the "Agreement") is made as of
_______________ by and between Cygnus, Inc., a Delaware corporation (the
"Corporation"), and ____________________ (the "Indemnitee").

                                    RECITALS

         The Corporation and Indemnitee recognize the increasing difficulty in
obtaining liability insurance for directors, officers and key employees, the
significant increases in the cost of such insurance and the general reductions
in the coverage of such insurance. The Corporation and Indemnitee further
recognize the substantial increase in corporate litigation in general,
subjecting directors, officers and key employees to expensive litigation risks
at the same time as the availability and coverage of liability insurance has
been severely limited. Indemnitee does not regard the current protection
available as adequate under the present circumstances, and Indemnitee and agents
of the Corporation may not be willing to continue to serve as agents of the
Corporation without additional protection. The Corporation desires to attract
and retain the services of highly qualified individuals, such as Indemnitee, and
to indemnify its directors, officers and key employees so as to provide them
with the maximum protection permitted by law.

                                    AGREEMENT

         In consideration of the mutual promises made in this Agreement, and for
other good and valuable consideration, receipt of which is hereby acknowledged,
the Corporation and Indemnitee hereby agree as follows:

         1. INDEMNIFICATION.

                  (a) THIRD-PARTY PROCEEDINGS. The Corporation shall indemnify
Indemnitee if Indemnitee is or was a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the Corporation) by reason of the fact that Indemnitee is or was a
director, officer, employee or agent of the Corporation, or any subsidiary of
the Corporation, by reason of any action or inaction on the part of Indemnitee
while an officer or director or by reason of the fact that Indemnitee is or was
serving at the request of the Corporation as a director, officer, employee or
agent of another corporation, partnership, joint venture, trust or other
enterprise, against expenses, liabilities, damages and losses (including
attorneys' fees), judgments, fines, excise taxes and amounts paid in settlement
(if the Corporation approves such settlement in advance, not be to unreasonably
withheld) actually and reasonably incurred or suffered by Indemnitee in
connection with such action, suit or proceeding if Indemnitee acted in good
faith and in a manner Indemnitee reasonably believed to be in or not opposed to
the best interests of the Corporation and, with respect to any criminal action
or proceeding, had no reasonable cause to believe Indemnitee's conduct was
unlawful. The termination of any action, suit or proceeding by judgment, order,
settlement, conviction, or upon a plea of nolo contendere or its equivalent,
shall not, of itself, create a presumption that Indemnitee did not act in good
faith and in a manner which Indemnitee reasonably believed to be

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in or not opposed to the best interests of the Corporation, and, with respect to
any criminal action or proceeding, shall not create a presumption that
Indemnitee had reasonable cause to believe that Indemnitee's conduct was
unlawful.

                  (b) PROCEEDINGS BY OR IN THE RIGHT OF THE CORPORATION. The
Corporation shall indemnify Indemnitee if Indemnitee was or is a party or is
threatened to be made a party to any threatened, pending or completed action or
proceeding by or in the right of the Corporation or any subsidiary of the
Corporation to procure a judgment in its favor by reason of the fact that
Indemnitee is or was a director, officer, employee or agent of the Corporation,
or any subsidiary of the Corporation, by reason of any action or inaction on the
part of Indemnitee while an officer or director or by reason of the fact that
Indemnitee is or was serving at the request of the Corporation as a director,
officer, employee or agent of another corporation, partnership, joint venture,
trust or other enterprise, against expenses, liabilities, damages and losses
(including attorneys' fees) and, to the fullest extent permitted by law, amounts
paid in settlement (if the Corporation approves such settlement in advance, not
to be unreasonably withheld), in each case to the extent actually and reasonably
incurred by Indemnitee in connection with the defense or settlement of such
action or suit if Indemnitee acted in good faith and in a manner Indemnitee
reasonably believed to be in or not opposed to the best interests of the
Corporation, except that no indemnification shall be made with respect to any
claim, issue or matter as to which Indemnitee shall have been finally
adjudicated by court order or judgment to be liable to the Corporation unless
and only to the extent that the Delaware Court of Chancery or the court in which
such action or proceeding is or was pending shall determine upon application
that, in view of all the circumstances of the case, Indemnitee is fairly and
reasonably entitled to indemnity for such expenses which such court shall deem
proper.

                  (c) MANDATORY PAYMENT OF EXPENSES. To the extent that
Indemnitee has been successful on the merits or otherwise in defense of any
action, suit or proceeding referred to in Section l(a) or Section l(b) or the
defense of any claim, issue or matter therein, Indemnitee shall be indemnified
against expenses (including attorneys' fees) actually and reasonably incurred by
Indemnitee in connection therewith.

         2. NO EMPLOYMENT RIGHTS. Nothing contained in this Agreement is
intended to create in Indemnitee any right to continued employment.

         3. EXPENSES; INDEMNIFICATION PROCEDURE.

                  (a) ADVANCEMENT OF EXPENSES. The Corporation shall advance all
expenses incurred by Indemnitee in connection with the investigation, defense,
settlement or appeal of any civil or criminal action, suit or proceeding
referred to in Section l(a) or Section l(b) of this Agreement (including amounts
actually paid in settlement of any such action, suit or proceeding as to which
Indemnitee is entitled to indemnification hereunder). Indemnitee hereby
undertakes to repay such amounts advanced only if, and to the extent that, it
shall ultimately be determined that Indemnitee is not entitled to be indemnified
by the Corporation as authorized hereby.

                  (b) NOTICE/COOPERATION BY INDEMNITEE. Indemnitee shall, as a
condition precedent to his or her right to be indemnified under this Agreement,
give the Corporation notice in writing as soon as practicable of any claim made
against Indemnitee for which


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indemnification will or could be sought under this Agreement. Notice to the
Corporation shall be directed to the Chief Executive Officer of the Corporation
and shall be given in accordance with the provisions of Section 12(d) below. In
addition, Indemnitee shall give the Corporation such information and cooperation
as it may reasonably require and as shall be within Indemnitee's power.

                  (c) PROCEDURE. Any indemnification and advances provided for
in Section 1 and this Section 3 shall be made no later than sixty (60) days
after receipt of the written request of Indemnitee. If a claim under this
Agreement, under any statute, or under any provision of the Corporation's
Certificate of Incorporation or By-laws providing for indemnification, is not
paid in full by the Corporation within sixty (60) days after a written request
for payment thereof has first been received by the Corporation, Indemnitee may,
but need not, at any time thereafter bring suit against the Corporation to
recover the unpaid amount of the claim and, subject to Section 11 of this
Agreement, Indemnitee shall also be entitled to be paid for the expenses
(including attorneys' fees) of bringing such suit. It shall be a defense to any
such action (other than an action brought to enforce a claim for expenses
incurred in defending any proceeding in advance of its final disposition where
the required undertaking if any is required, has been tendered to the
Corporation) that Indemnitee has not met the standards of conduct which makes it
permissible under the General Corporation Law of the State of Delaware for the
Corporation to indemnify Indemnitee for the amount claimed, but the burden of
proving such defense shall be on the Corporation and Indemnitee shall be
entitled to receive interim payments of expenses pursuant to Section 3(i) unless
and until such defense may be finally adjudicated by court order or judgment
from which no further right of appeal exists. It is the parties' intention that
if the Corporation contests Indemnitee's right to indemnification, such question
shall be for the court to decide, and neither the failure of the Corporation
(including its Board of Directors, any committee or subgroup of the Board of
Directors, independent legal counsel, or its shareholders) to have made a
determination that indemnification of Indemnitee is proper in the circumstances
because Indemnitee has met the applicable standard of conduct required by
applicable law, nor an actual determination by the Corporation (including its
Board of Directors, any committee or subgroup of the Board of Directors,
independent legal counsel, or its shareholders) that Indemnitee has not met such
applicable standard of conduct, shall create a presumption that Indemnitee has
or has not met the applicable standard of conduct.

                  (d) NOTICE TO INSURERS. If, at the time the Corporation
receives notice of a claim pursuant to Section 3(b) hereof, it has director and
officer liability insurance in effect, the Corporation shall give prompt notice
of such proceedings to the insurers in accordance with the procedures set forth
in the respective policies. The Corporation shall thereafter take all necessary
or desirable action to cause such insurers to pay, on behalf of the Indemnitee,
all amounts payable as a result of such proceeding in accordance with the terms
of such policies.

                  (e) SELECTION OF COUNSEL. In the event Section 3(a) hereof
obligates the Corporation to pay the expenses of any proceeding against
Indemnitee, the Corporation, if appropriate, shall be entitled to assume the
defense of such proceeding, with counsel approved by Indemnitee, upon the
delivery to Indemnitee of written notice of its election so to do. After
delivery of such notice, approval of such counsel by Indemnitee and the
retention of such counsel by the Corporation, the Corporation will not be liable
to Indemnitee under this Agreement for any fees of counsel subsequently incurred
by Indemnitee with respect to the same

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proceeding, provided that (i) Indemnitee shall have the right to employ counsel
in any such proceeding at Indemnitee's expense; and (ii) if (a) the Corporation
previously authorized the Indemnitee's employment, (b) Indemnitee shall have
reasonably concluded that there may be a conflict of interest between the
Corporation and Indemnitee in the conduct of any such defense or (c) the
Corporation shall not, in fact, have employed counsel to assume the defense of
such proceeding, then the fees and expenses of Indemnitee's counsel shall be at
the expense of the Corporation.

         4. ADDITIONAL INDEMNIFICATION RIGHTS; NONEXCLUSIVITY.

                  (a) SCOPE. Notwithstanding any other provision of this
Agreement, the Corporation hereby agrees to indemnify the Indemnitee to the
fullest extent permitted by law, notwithstanding that such indemnification is
not specifically authorized by the other provisions of this Agreement, the
Corporation's Certificate of Incorporation, the Corporation's By-laws or by
statute. In the event of any change, after the date of this Agreement, in any
applicable law, statute, or rule expanding the right of a Delaware corporation
to indemnify a member of its board of directors or an officer, such changes
shall be deemed to be within the purview of Indemnitee's rights and the
Corporation's obligations under this Agreement. In the event of any change in
any applicable law, statute or rule narrowing the right of a Delaware
corporation to indemnify a member of its board of directors or an officer, such
changes, to the extent not otherwise required by such law, statute or rule to be
applied to this Agreement shall have no effect on this Agreement or the parties'
rights and obligations hereunder.

                  (b) NONEXCLUSIVITY. The indemnification provided by this
Agreement shall not be deemed exclusive of any rights to which Indemnitee may be
entitled under the Corporation's Certificate of Incorporation, its By-laws, any
agreement, any vote of stockholders or disinterested members of the
Corporation's Board of Directors, the General Corporation Law of the State of
Delaware, or otherwise, both as to action in Indemnitee's official capacity and
as to action in another capacity while holding such office. The indemnification
provided under this Agreement shall continue as to Indemnitee for any action
taken or not taken while serving in an indemnified capacity even though he or
she may have ceased to serve in any such capacity at the time of any action,
suit or other covered proceeding.

         5. PARTIAL INDEMNIFICATION. If Indemnitee is entitled under any
provision of this Agreement to indemnification by the Corporation for some or a
portion of the expenses, judgments, fines or penalties actually or reasonably
incurred in the investigation, defense, appeal or settlement of any civil or
criminal action, suit or proceeding, but not, however, for the total amount
thereof, the Corporation shall nevertheless indemnify Indemnitee for the portion
of such expenses, judgments, fines or penalties to which Indemnitee is entitled.

         6. MUTUAL ACKNOWLEDGMENT. Both the Corporation and Indemnitee
acknowledge that in certain instances, federal law or public policy may override
applicable state law and prohibit the Corporation from indemnifying its
directors and officers under this Agreement or otherwise. For example, the
Corporation and Indemnitee acknowledge that the Securities and Exchange
Commission (the "SEC") has taken the position that indemnification is not
permissible for liabilities arising under certain federal securities laws, and
federal legislation prohibits indemnification for certain violations of the
Employee Retirement Income Security Act of 1974


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("ERISA"). Indemnitee understands and acknowledges that the Corporation has
undertaken or may be required in the future to undertake with the SEC to submit
the question of indemnification to a court in certain circumstances for a
determination of the Corporation's right under public policy to indemnify
Indemnitee.

         7. OFFICER AND DIRECTOR LIABILITY INSURANCE. The Corporation shall,
from time to time, make the good faith determination whether or not it is
practicable for the Corporation to obtain and maintain a policy or policies of
insurance with reputable insurance companies providing the officers and
directors of the Corporation with coverage for losses from wrongful acts, or to
ensure the Corporation's performance of its indemnification obligations under
this Agreement. Among other considerations, the Corporation will weigh the costs
of obtaining such insurance coverage against the protection afforded by such
coverage. In all policies of director and officer liability insurance,
Indemnitee shall be named as an insured in such a manner as to provide
Indemnitee the same rights and benefits as are accorded to the most favorably
insured of the Corporation's directors, if Indemnitee is a director; or of the
Corporation's officers, if Indemnitee is not a director of the Corporation but
is an officer; or of the Corporation's key employees, if Indemnitee is not an
officer or director but is a key employee. Notwithstanding the foregoing, the
Corporation shall have no obligation to obtain or maintain such insurance if the
Corporation determines in good faith that such insurance is not reasonably
available, if the premium costs for such insurance are disproportionate to the
amount of coverage provided, if the coverage provided by such insurance is
limited by exclusions so as to provide an insufficient benefit, or if Indemnitee
is covered by similar insurance maintained by a parent or subsidiary of the
Corporation.

         8. SEVERABILITY. Nothing in this Agreement is intended to require or
shall be construed as requiring the Corporation to do or fail to do any act in
violation of applicable law. The Corporation's inability, pursuant to court
order, to perform its obligations under this Agreement shall not constitute a
breach of this Agreement. The provisions of this Agreement shall be severable as
provided in this Section 8. If this Agreement or any portion hereof shall be
invalidated on any ground by any court of competent jurisdiction, then the
Corporation shall nevertheless indemnify Indemnitee to the full extent permitted
by any applicable portion of this Agreement that shall not have been
invalidated, and the balance of this Agreement not so invalidated shall be
enforceable in accordance with its terms.

         9. EXCEPTIONS. Any other provision herein to the contrary
notwithstanding, the Corporation shall not be obligated pursuant to the terms of
this Agreement:

                  (a) CLAIMS INITIATED BY INDEMNITEE. To indemnify or advance
expenses to Indemnitee with respect to proceedings or claims initiated or
brought voluntarily by Indemnitee and not by way of defense, except with respect
to proceedings brought to establish or enforce a right to indemnification under
this Agreement or any other statute or law or otherwise as required under
Section 145 of the Delaware General Corporation Law, but such indemnification or
advancement of expenses may be provided by the Corporation in specific cases if
the Board of Directors finds it to be appropriate;

                  (b) LACK OF GOOD FAITH. To indemnify Indemnitee for any
expenses incurred by Indemnitee with respect to any proceeding instituted by
Indemnitee to enforce or interpret this

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Agreement, if a court of competent jurisdiction determines that each of the
material assertions made by Indemnitee in such proceeding was not made in good
faith or was frivolous or the court determines that indemnification hereunder is
unlawful;

                  (c) INSURED CLAIMS. To indemnify Indemnitee for expenses or
liabilities of any type whatsoever (including, but not limited to, judgments,
fines, ERISA excise taxes or penalties, and amounts paid in settlement) if, and
then only to the extent that, such expenses or liabilities have been paid
directly to Indemnitee by an insurance carrier under a policy of officers' and
directors' liability insurance maintained by the Corporation; or

                  (d) CLAIMS UNDER SECTION 16(b). To indemnify Indemnitee for
expenses or the payment of profits arising from the purchase and sale by
Indemnitee of securities in violation of Section 16(b) of the Securities
Exchange Act of 1934, as amended, or any similar successor statute.

         10. CONSTRUCTION OF CERTAIN PHRASES.

                  (a) For purposes of this Agreement, references to the
"Corporation" shall include, in addition to the resulting corporation, any
constituent corporation (including any constituent of a constituent) absorbed in
a consolidation or merger which, if its separate existence had continued, would
have had power and authority to indemnify its directors, officers, and employees
or agents, so that if Indemnitee is or was a director, officer, employee or
agent of such constituent corporation, or is or was serving at the request of
such constituent corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise,
Indemnitee shall stand in the same position under the provisions of this
Agreement with respect to the resulting or surviving corporation as Indemnitee
would have with respect to such constituent corporation if its separate
existence had continued.

                  (b) For purposes of this Agreement, references to "other
enterprises" shall include employee benefit plans; references to "fines" shall
include any excise taxes assessed on Indemnitee with respect to an employee
benefit plan; and references to "serving at the request of the Corporation"
shall include any service as a director, officer, employee or agent of the
Corporation imposing duties on, or involving services by, such director,
officer, employee or agent with respect to an employee benefit plan, its
participants, or beneficiaries; and if Indemnitee acted in good faith and in a
manner Indemnitee reasonably believed to be in the interest of the participants
and beneficiaries of an employee benefit plan, Indemnitee shall be deemed to
have acted in a manner "not opposed to the best interests of the Corporation" as
referred to in this Agreement.

         11. ATTORNEYS' FEES. In the event that any action is instituted by
Indemnitee under this Agreement to enforce or interpret any of the terms hereof,
Indemnitee shall be entitled to be paid all court costs and expenses, including
reasonable attorneys' fees, incurred by Indemnitee with respect to such action,
unless as a part of such action, the court of competent jurisdiction determines
that each of the material assertions made by Indemnitee as a basis for such
action were not made in good faith or were frivolous. In the event of an action
instituted by or in the name of the Corporation under this Agreement or to
enforce or interpret any of the terms of this Agreement, Indemnitee shall be
entitled to be paid all court costs and expenses, including

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attorneys' fees, incurred by Indemnitee in defense of such action (including
with respect to Indemnitee's counterclaims and cross-claims made in such
action), unless as a part of such action the court determines that each of
Indemnitee's material defenses to such action were made in bad faith or were
frivolous.

         12. MISCELLANEOUS.

                  (a) GOVERNING LAW. This Agreement and all acts and
transactions pursuant hereto and the rights and obligations of the parties
hereto shall be governed, construed and interpreted in accordance with the laws
of the State of Delaware, without giving effect to principles of conflicts of
law.

                  (b) ENTIRE AGREEMENT; ENFORCEMENT OF RIGHTS. This Agreement
sets forth the entire agreement and understanding of the parties relating to the
subject matter herein and merges all prior discussions between them. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, shall be effective unless signed in writing by the parties
to this Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

                  (c) CONSTRUCTION. This Agreement is the result of negotiations
between and has been reviewed by each of the parties hereto and their respective
counsel, if any; accordingly, this Agreement shall be deemed to be the product
of all of the parties hereto, and no ambiguity shall be construed in favor of or
against any one of the parties hereto.

                  (d) NOTICES. Any notice, demand or request required or
permitted to be given under this Agreement shall be in writing and shall be
deemed sufficient when delivered personally or sent by telegram or fax or
forty-eight (48) hours after being deposited in the U.S. mail, as certified or
registered mail, with postage prepaid, and addressed to the party to be notified
at such party's address as set forth below or as subsequently modified by
written notice.

                  (e) COUNTERPARTS. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

                  (f) SUCCESSORS AND ASSIGNS. This Agreement shall be binding
upon the Corporation and its successors and assigns, and inure to the benefit of
Indemnitee and Indemnitee's heirs, legal representatives and assigns.

                  (g) SUBROGATION. In the event of payment under this Agreement,
the Corporation shall be subrogated to the extent of such payment to all of the
rights of recovery of Indemnitee, who shall execute all documents required and
shall do all acts that may be necessary to secure such rights and to enable the
Corporation to effectively bring suit to enforce such rights.

                  (h) CONCLUSIVE PRESUMPTION REGARDING STANDARDS OF CONDUCT. The
Indemnitee shall be conclusively presumed to have met the relevant standards of
conduct, if any, as defined by Delaware General Corporation Law, for
indemnification pursuant to this Agreement, unless a determination is made that
the Indemnitee has not met such standards in a


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written opinion by independent counsel to the Corporation, selection of whom has
been approved by the Indemnitee in writing, or by a court of competent
jurisdiction.




                            [Signature Page Follows]





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         The parties hereto have executed this Agreement as of the day and year
set forth on the first page of this Agreement.

                                               Cygnus, Inc.


                                               By:
                                                     ---------------------------

                                               Title:
                                                     ---------------------------

                                               Address:   400 Penobscot Drive
                                                          Redwood City, CA 94063

AGREED TO AND ACCEPTED:




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Address:
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