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                                                                   EXHIBIT 10.13

                       CORCEPT THERAPEUTICS INCORPORATED

                    CONSULTING, CONFIDENTIAL INFORMATION AND
                              INVENTIONS AGREEMENT

     In consideration and as a condition of his engagement as a consultant to
Corcept Therapeutics Incorporated, a Delaware corporation (which together with
any parent, subsidiary, affiliate, or successor is hereinafter referred to as
the "Company"), and effective as of May 31, 1999 (the "Effective Date"), Alan
Schatzberg, M.D. ("Consultant") hereby agrees as follows:

     1. CONSULTING PERIOD
        -----------------

     Consultant accepts engagement by the Company as a consultant beginning on
the Effective Date and continuing until May   , 2000, which one-year term will
                                            --
be automatically extended for additional one-year periods unless terminated by
either party by delivery of written notice at least six months prior to the end
of a term. During such time, Consultant agrees to provide to the Company those
services set forth on Exhibit A and to perform such services at such time and
place as may be reasonably designated by the Company; provided that services
provided by Consultant will be consistent with Consultant's duties to Stanford
University.

     2. COMPENSATION
        ------------

     As full consideration for the consulting services and the other
undertakings hereunder, Consultant agrees to accept the compensation provided
for in Exhibit A. In addition to the compensation provided for in Exhibit A, the
Company shall reimburse Consultant for all reasonable out-of-pocket travel and
other expenses that have been incurred by Consultant at the request of the
Company in the performance of the consulting services and which have been
approved in advance in writing by the Company. The Company will reimburse such
expenses within 30 days after Consultant has provided to the Company, in form
and content reasonably satisfactory to the Company, appropriate documentation
evidencing such expenses.

     3. CONFIDENTIALITY OBLIGATION
        --------------------------

     Consultant will hold all Company Confidential Information in confidence and
will not disclose, use, copy, publish, summarize, or remove from the Company's
premises any Confidential Information, except (a) as necessary to carry out
Consultant's specified services, and (b) after termination of the consulting
period, as specifically authorized in writing by an officer of the Company.
"Confidential Information" is all information related to any aspect of the
Company's business which is either information not known by

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actual or potential competitors of the Company or is proprietary information of
the Company, whether of a technical nature or otherwise. Confidential
Information includes but is not limited to products, inventions, ideas,
discoveries, designs, methods, formulas, assays, cell lines, software,
databases, algorithms, trade secrets, works of authorship, mask works,
developmental or experimental work, processes, techniques, improvements,
know-how, licenses, data, financial information and forecasts, product plans,
marketing plans and strategies, and customer lists. Consultant's non-disclosure
obligations set forth herein apply with respect to all third parties, including
without limitation other persons or legal entities for whom Consultant currently
performs or may perform in the future services. Consultant will not, either
during or after the term of this Agreement, directly or indirectly submit for
publication or publish any Confidential Information of the Company without the
prior written consent of the Company. Upon expiration or termination of this
Agreement for any reason, Consultant shall immediately deliver to the Company
all documentation and information, in whatever form, including all copies,
concerning Confidential Information of the Company, including without limitation
any information generated by Consultant (alone or with others) as a result of
his consulting services on behalf of the Company, or from access to the Company
Confidential Information, and shall make no further use thereof.

     4. INFORMATION OF OTHERS
        ---------------------

     Consultant will safeguard and keep confidential the proprietary information
of customers, vendors, consultants, and other parties with which the Company
does business to the same extent as if it were Company Confidential Information.
Consultant will not, during his consulting period with the Company or otherwise,
use or disclose to the Company any confidential, trade secret, or other
proprietary information or material of any other person, and Consultant will not
bring onto the Company's premises any unpublished document or any other property
belonging to any other person without the written consent of that other person.

     5. COMPANY PROPERTY
        ----------------

     All papers, records, data, notes, drawings, files; documents, samples,
devices, products, equipment, and other materials, including copies, relating to
the Company's business that Consultant possesses or creates as a result of his
consulting services with the Company, whether or not confidential, are the sole
and exclusive property of the Company. In the event of the expiration or
termination of the consulting period for any reason, Consultant will promptly
deliver all such materials to the Company and will sign and deliver to the
Company the "Termination Certificate" attached hereto as Exhibit B and made a
part hereof.

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     6. OWNERSHIP OF INVENTIONS
        -----------------------

     All products, inventions, ideas, discoveries, designs, methods, formulas,
assays, cell lines, software, databases, algorithms, trade secrets, works of
authorship, mask works, developments, processes, techniques, improvements, and
related know-how which result from the services Consultant provides, alone or
with others, on behalf of the Company or from access to the Company Confidential
Information or property, whether or not patentable, copyrightable, or qualified
for mask work protection (collectively "Inventions") shall be the sole and
exclusive property of the Company. Consultant hereby assigns and agrees to
assign to the Company or its designee, without further consideration, its entire
right, title, and interest in and to all Inventions, including all rights to
obtain, register, perfect, and enforce patents, copyrights, mask work rights,
and other intellectual property protection for Inventions. Consultant will
disclose promptly and in writing to the individual designated by the Company
all Inventions which Consultant made or reduced to practice. During the
consulting period and for four years thereafter, Consultant will assist the
Company (at its expense) to obtain and enforce patents, copyrights, mask work
rights, and other forms of intellectual property protection on Inventions.

     7. PRIOR CONTRACTS
        ---------------

     Consultant represents and warrants that there are no other contracts to
assign inventions that are now in existence between any other person or entity
and Consultant with respect to the services to be provided by the Consultant.
Consultant further represents and warrants that he has no other employment,
consultancies, or undertakings which would restrict or impair his performance
of this Agreement.

     8. AGREEMENTS WITH THIRD PARTIES
        -----------------------------

     Consultant acknowledges that the Company from time to time may have
agreements with other persons or with the United States Government or agencies
thereof which impose obligations or restrictions on the Company regarding
Inventions made during the course of work under such agreements or regarding the
confidential nature of such work. Consultant agrees to be bound by all such
obligations or restrictions and to take all action necessary to discharge the
obligations of the Company thereunder.

     9. REPRESENTATIONS AND WARRANTIES OF CONSULTANT
        --------------------------------------------

     Consultant represents and warrants that the results of his consulting
services under this Agreement ("Work Product") will be the sole product of his
own efforts; that Consultant shall be the sole and exclusive owner of all rights
in such Work Product, and have the unrestricted right to assign Consultant's
rights with respect to such Work Product in the Company in accordance with
Section 6; and that the use and disclosure of

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such Work Product by Consultant to the Company will not infringe upon or violate
any patent, copyright, trade secret or other proprietary right of any third
party.

     10. INDEMNIFICATION
         ---------------

     Consultant agrees to defend, indemnify and hold harmless the Company and
its directors, officers, agents and employees from and against all claims,
losses, liabilities, damages, expenses and costs (including reasonable
attorney's fees and costs of litigation regardless of outcome) which result from
a breach or alleged breach of any of the representations and warranties
contained in Sections 7 or 9.

     11. MISCELLANEOUS
         -------------

          11.1 Governing Law. This Agreement shall be governed by, and construed
               -------------
in accordance with, the laws of the State of California, excluding those laws
that direct the application of the laws of another jurisdiction.

          11.2 Severability. If any provision of this Agreement shall be
               ------------
determined to be invalid or unenforceable for any reason, that provision shall
be adjusted rather than voided, if possible, in order to achieve the intent of
the parties to the extent possible. In any event, all other provisions of this
Agreement, shall be deemed valid, and enforceable to the full extent possible.

          11.3 Injunctive Relief Consent to Jurisdiction. Consultant
               -----------------------------------------
acknowledges and agrees that damages will not be an adequate remedy in the event
of a breach of any of his obligations under this Agreement. Consultant therefore
agrees that the Company shall be entitled (without limitation of any other
rights or remedies otherwise available to the Company) to obtain, without
posting bond, specific performance and preliminary and permanent injunction from
any court of competent jurisdiction prohibiting the continuance or recurrence of
any breach of this Agreement. Consultant hereby submits to the jurisdiction and
venue of the courts of the State of California for purposes of any such action.
Consultant further agrees that service upon him in any such action or proceeding
may be made by first class mail, certified or registered, to the address as last
appearing on the records of the Company.

          11.4 Binding Effect: Waiver. This Agreement shall be binding upon and
               ----------------------
shall inure to the benefit of the successors and assigns of the parties. The
waiver by the Company of a breach of any provision of this Agreement shall not
operate or be construed as a waiver of any subsequent breach of the same or any
other provision hereof.

          11.5 Headings. The Section headings herein are intended for reference
               --------
and shall not by themselves determine the construction or interpretation of this
Agreement.

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          11.6 Entire Agreement: Modifications. This Consulting, Confidential
               -------------------------------
Information and Inventions Agreement and the Exhibits attached hereto contain
the entire agreement between the Company and the Consultant concerning the
subject matter hereof and supersede any and all prior and contemporaneous
negotiations, correspondence, understandings, and agreements, whether oral or
written, respecting that subject matter. All modifications to this Agreement
shall be in writing and signed by the party against whom enforcement of such
modification is sought.

          11.7 Assignment. Consultant may not assign or transfer this Agreement
               ----------
in whole or in part to any other party, nor does Consultant have the right to
delegate or subcontract any of his duties, rights or obligations hereunder
without the prior written consent of the Company, and any attempted assignment,
transfer, delegation or subcontracting without the prior written consent of the
Company shall be null and void.

          11.8 Independent Contractor. Consultant understands and agrees that he
               ----------------------
shall operate as and have the status of an independent contractor, and shall not
act as or be the agent or employee of the Company. Consultant shall maintain
appropriate worker's compensation and liability insurance and shall provide
Company evidence of such insurance upon request. Consultant shall be responsible
for payment of all applicable taxes in respect to compensation paid hereunder
and shall provide evidence of such payment upon request.

     12. TERMINATION AND SURVIVAL.
         ------------------------

     The Company shall have the right to terminate this Agreement with or
without cause at any time upon 30 days advance written notice to Consultant.
Sections 3, 4, 5, 6, 7, 8, 9, 10, 11 and this Section 12 shall survive
expiration or termination of this Agreement for any reason, and shall remain in
full force and effect.

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     IN WITNESS WHEREOF, I have executed this Consulting, Confidential
Information and Inventions Agreement as of the 31st day of May, 1999.


                                        /s/ Alan Schatzberg, M.D.
                                        ----------------------------------------
                                        Signature

                                        Alan Schatzberg
                                        ----------------------------------------
                                        Name of Consultant



RECEIPT ACKNOWLEDGED:

CORCEPT THERAPEUTICS INCORPORATED


By: /s/ David B. Singer
    ------------------------------

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                                    EXHIBIT A

                       Corcept Therapeutics Incorporated

                    DESCRIPTION OF SERVICES AND COMPENSATION



Consulting services as may be assigned by the Board of Directors from time to
time.


Compensation: $40,000 per year

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                                   EXHIBIT B

                       Corcept Therapeutics Incorporated

                           TERMINATION CERTIFICATION


     This is to certify that the undersigned does not have in his possession,
nor has the undersigned failed to return, any papers records, data, notes,
drawings, files, documents, samples, devices, products, equipment, and other
materials, including reproductions of any of the aforementioned items, belonging
to the Company, its subsidiaries, affiliates, successors, or assigns, (together,
the "Company").

     The undersigned further certifies that he has complied with all the terms
of the Company's Confidential Information and Inventions Agreement signed by
the undersigned, including the reporting of any inventions and original works of
authorship (as defined therein) conceived or made by the undersigned (solely or
jointly with others) covered by that agreement.

     The undersigned further agrees that, in compliance with the Confidential
Information and Inventions Agreement, he will hold in confidence and will not
disclose, use, copy, publish, or summarize any Confidential Information (as
defined in the Company's Confidential Information and Inventions Agreement) of
the Company or of any of its customers, vendors, consultants, and other parties
with which it does business.

Date:
      ------------------------


                                        ----------------------------------------
                                        Signature


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                                        Type/Print Name