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                                                                     EXHIBIT 4.1


                         [FORM OF SHAREHOLDER AGREEMENT]

          SHAREHOLDER AGREEMENT, dated as of August 10, 1998, among GUIDANT
CORPORATION, an Indiana corporation ("Parent"), PEGASUS ACQUISITIONS CORP., a
Delaware corporation and a wholly-owned subsidiary of Parent ("Sub"), and the
persons listed on Schedule A hereto (the "Shareholders").

          WHEREAS, Parent, Sub and InControl, Inc., a Delaware corporation (the
"Company"), propose to enter into an Agreement and Plan of Merger, dated the
date hereof (as the same may be amended or supplemented, the "Merger Agreement")
providing for (i) the making of a cash tender offer (as such offer may be
amended from time to time as permitted under the Merger Agreement, the "Offer")
by Sub for all the outstanding shares of Common Stock, par value $0.01 per
share, of the Company (the "Company Common Stock") and (ii) the merger of Sub
with the Company (the "Merger");

          WHEREAS, each Shareholder is the record and beneficial owner of the
number of shares of Company Common Stock set forth opposite such Shareholder's
name on Schedule A hereto; such shares of Company Common Stock, as such shares
may be adjusted by stock dividend, stock split, recapitalization, combination or
exchange of shares, merger, consolidation, reorganization or other change or
transaction of or by the Company, together with shares of Company Common Stock
that may be acquired after the date hereof by such Shareholder, including shares
of Company Common Stock issuable upon the exercise of options to purchase
Company Common Stock (as the same may be adjusted as aforesaid), being
collectively referred to herein as the "Shares"; and

          WHEREAS, as a condition to their willingness to enter into the Merger
Agreement, Parent and Sub have requested that the Shareholders enter into this
Agreement;

          NOW, THEREFORE, to induce Parent and Sub to enter into, and in
consideration of their entering into, the Merger Agreement, and in consideration
of the promises and the representations, warranties and agreements contained
herein, the parties agree as follows:

          1. Tender of Shares.

          Each Shareholder hereby agrees that it shall tender its Shares into
the Offer and that it shall not withdraw any Shares so tendered.

          2. Representations and Warranties of the Shareholders. Each
Shareholder hereby represents and warrants severally and not jointly to Parent
and Sub as follows:

          (a) Authority. The Shareholder has all requisite power and authority
to execute and deliver this Agreement and to consummate the transactions
contemplated hereby. The execution, delivery and performance of this Agreement
and the consummation of the 



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transactions contemplated hereby have been duly authorized by the Shareholder.
This Agreement has been duly executed and delivered by the Shareholder and,
assuming this Agreement constitutes a valid and binding obligation of Parent and
Sub, constitutes a valid and binding obligation of the Shareholder enforceable
against the Shareholder in accordance with its terms, subject to applicable
bankruptcy, insolvency, moratorium or other similar laws relating to creditors'
rights and general principles of equity (the "Enforceability Exceptions").
Except for the expiration or termination of the waiting periods under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act")
and filings with the Securities and Exchange Commission, neither the execution,
delivery or performance of this Agreement by the Shareholder nor the
consummation by the Shareholder of the transactions contemplated hereby will (i)
require any filing with, or permit, authorization, consent or approval of, any
federal, state, local or foreign government or any court, tribunal,
administrative agency or commission or other governmental or regulatory
authority or agency, domestic, foreign or supranational (a "Governmental
Entity"), (ii) result in a violation or breach of, or constitute (with or
without due notice or lapse of time or both) a default under, or give rise to
any right of termination, amendment, cancellation or acceleration under, or
result in the creation of any pledge, claim, lien, charge, encumbrance or
security interest of any kind or nature whatsoever (a "Lien") upon any of the
properties or assets of the Shareholder under, or require consent pursuant to,
any of the terms, conditions or provisions of any note, bond, mortgage,
indenture, lease, license, permit, concession, franchise, contract, agreement or
other instrument or obligation (a "Contract") to which the Shareholder is a
party or by which the Shareholder or any of the Shareholder's properties or
assets, including the Shareholder's Shares, may be bound or (iii) violate any
judgment, order, writ, preliminary or permanent injunction or decree (an
"Order") or any statute, law, ordinance, rule or regulation of any Governmental
Entity (a "Law") applicable to the Shareholder or any of the Shareholder's
properties or assets, including the Shareholder's Shares.

          (b) The Shares. The Shareholder's Shares and the certificates
representing such Shares are now, and at all times during the term hereof will
be, held by such Shareholder, or by a nominee or custodian for the benefit of
such Shareholder, and the Shareholder has good and marketable title to such
Shares, free and clear of any Liens, proxies, voting trusts or agreements,
understandings or arrangements, except for any such Liens or proxies arising
hereunder. The Shareholder owns of record or beneficially no shares of Company
Common Stock other than such Shareholder's Shares and shares of Company Common
Stock issuable upon the exercise of Company Stock Options.

          (c) Brokers. No broker, investment banker, financial advisor or other
person is entitled to any broker's, finder's, financial advisor's or other
similar fee or commission in connection with the transactions contemplated by
this Agreement based upon arrangements made by or on behalf of such Shareholder.

          (d) Merger Agreement. The Shareholder understands and acknowledges
that Parent is entering into, and causing Sub to enter into, the Merger
Agreement in reliance upon the Shareholder's execution and delivery of this
Agreement.



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          3. Representations and Warranties of Parent and Sub. Parent and Sub
hereby jointly and severally represent and warrant to the Shareholders as
follows:

          (a) Authority. Parent and Sub have the requisite corporate power and
authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby. The execution, delivery and performance of
this Agreement by Parent and Sub and the consummation of the transactions
contemplated hereby have been duly authorized by all necessary corporate action
on the part of Parent and Sub. This Agreement has been duly executed and
delivered by Parent and Sub and, assuming this Agreement constitutes a valid and
binding obligation of the Shareholders, constitutes a valid and binding
obligation of Parent and Sub enforceable in accordance with its terms, subject
to the Enforceability Exceptions.

          (b) Securities Act. The Shares will be acquired in compliance with,
and Sub will not offer to sell or otherwise dispose of any Shares so acquired by
it in violation of any of, the Securities Exchange Act of 1934 or the
registration requirements of the Securities Act of 1933.

          4. Covenants of the Shareholders. Each Shareholder agrees as follows:

          (a) The Shareholder shall not, except as contemplated by the terms of
this Agreement, (i) sell, transfer, pledge, assign or otherwise dispose of, or
enter into any Contract, option or other arrangement (including any profit
sharing arrangement) or understanding with respect to the sale, transfer,
pledge, assignment or other disposition of, or grant or suffer to exist any Lien
with respect to, the Shares to any person other than Sub or Sub's designee, (ii)
enter into any voting arrangement, whether by proxy, voting agreement, voting
trust, power-of-attorney or otherwise, with respect to the Shares or (iii) take
any other action that would in any way restrict, limit or interfere with the
performance of its obligations hereunder or the transactions contemplated
hereby.

          (b) Until the Merger is consummated or the Merger Agreement is
terminated, the Shareholder shall not, nor shall the Shareholder cause any
investment banker, financial adviser, attorney, accountant or other
representative or agent of the Shareholder to, directly or indirectly (i)
solicit, initiate or encourage (including by way of furnishing information), or
take any other action designed or reasonably likely to facilitate, any inquiries
or the making of any proposal which constitutes, or may reasonably be expected
to lead to, any Takeover Proposal or (ii) participate in any discussions or
negotiations regarding any Takeover Proposal.

          (c) At any meeting of shareholders of the Company called to vote upon
the Merger and the Merger Agreement or at any adjournment thereof or in any
other circumstances upon which a vote, consent or other approval (including by
written consent) with respect to the Merger and the Merger Agreement is sought,
each Shareholder shall, including by initiating a written consent solicitation
if requested by Parent, vote (or cause to be voted) such Shareholder's Shares in
favor of the Merger, the adoption by the Company of the Merger Agreement and the
approval of the other 



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transactions contemplated by the Merger Agreement. At any meeting of
shareholders of the Company or at any adjournment thereof or in any other
circumstances upon which the Shareholder's vote, consent or other approval is
sought, such Shareholder shall vote (or cause to be voted) such Shareholder's
Shares against (i) any merger agreement or merger (other than the Merger
Agreement and the Merger), consolidation, combination, sale of assets,
reorganization, recapitalization, dissolution, liquidation or winding up of or
by the Company or any other Takeover Proposal (collectively, "Alternative
Transactions") or (ii) any amendment of the Company's Certificate of
Incorporation or By-laws or other proposal or transaction involving the Company
or any of its subsidiaries, which amendment or other proposal or transaction
would in any manner impede, frustrate, prevent or nullify the Offer, the Merger,
the Merger Agreement or any of the other transactions contemplated by the Merger
Agreement (collectively, "Frustrating Transactions").

          5. Grant of Irrevocable Proxy; Appointment of Proxy. (a) Each
Shareholder hereby irrevocably grants to, and appoints, each of James M.
Cornelius, Ronald W. Dollens, and J. B. King and any other individual who shall
hereafter be designated by Parent, and each of them, such Shareholder's proxy
and attorney-in-fact (with full power of substitution), for and in the name,
place and stead of such Shareholder, to vote such Shareholder's Shares, or grant
a consent or approval in respect of such Shares, at any meeting of shareholders
of the Company or at any adjournment thereof or in any other circumstances upon
which their vote, consent or other approval is sought, (i) in favor of the
Merger, the adoption by the Company of the Merger Agreement and the approval of
the other transactions contemplated by the Merger Agreement and against (i) any
merger agreement or merger (other than the Merger Agreement and the Merger),
consolidation, combination, sale of assets, reorganization, recapitalization,
dissolution, liquidation or winding up of or by the Company and (ii) any
Alternative Transaction or Frustrating Transaction.

          (b) Each Shareholder represents that any proxies heretofore given in
respect of such Shareholder's Shares are not irrevocable, and that any such
proxies are hereby revoked.

          (c) Each Shareholder hereby affirms that the irrevocable proxy set
forth in this Section 5 is given in connection with the execution of the Merger
Agreement, and that such irrevocable proxy is given to secure the performance of
the duties of such Shareholder under this Agreement. Such Shareholder hereby
further affirms that the irrevocable proxy is coupled with an interest and may
under no circumstances be revoked, subject to Section 8. Such Shareholder hereby
ratifies and confirms all that such irrevocable proxy may lawfully do or cause
to be done by virtue hereof. Such irrevocable proxy is executed and intended to
be irrevocable in accordance with the provisions of Section 212 of the Delaware
General Corporation Law. Such irrevocable proxy shall be valid until the
termination of this Agreement pursuant to Section 8.

          6. Further Assurances. Each Shareholder will, from time to time,
execute and deliver, or cause to be executed and delivered, such additional or
further transfers, 



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assignments, endorsements, consents and other instruments as Parent or Sub may
reasonably request for the purpose of effectively carrying out the transactions
contemplated by this Agreement and to vest the power to vote such Shareholder's
Shares as contemplated by Section 5. Parent and Sub jointly and severally agree
to use reasonable efforts to take, or cause to be taken, all actions necessary
to comply promptly with all legal requirements that may be imposed with respect
to the transactions contemplated by this Agreement (including legal requirements
of the HSR Act).

          7. Assignment. Neither this Agreement nor any of the rights, interests
or obligations hereunder shall be assigned by any of the parties without the
prior written consent of the other parties, except that Sub may assign, in its
sole discretion, any or all of its rights, interests, liabilities and
obligations hereunder to Parent or to any wholly owned subsidiary of Parent,
upon which assignment Sub shall be relieved of and released from its liabilities
and obligations hereunder. Subject to the preceding sentence, this Agreement
will be binding upon, inure to the benefit of and be enforceable by the parties
and their respective successors and assigns. Each Shareholder agrees that this
Agreement and the obligations of such Shareholder hereunder shall attach to such
Shareholder's Shares and shall be binding upon any person or entity to which
legal or beneficial ownership of such Shares shall pass, whether by operation of
law or otherwise, including without limitation such Shareholder's heirs,
guardians, administrators or successors.

          8. Termination. This Agreement, and all rights and obligations of the
parties hereunder, shall terminate upon the earliest of (a) the date upon which
the Merger Agreement is terminated pursuant to Section 8.1(a) thereof, (b) the
date upon which the Merger Agreement is terminated pursuant to Section 8.1(e)
thereof, (c) the later of (i) the first anniversary of the date of termination
of the Merger Agreement other than pursuant to Section 8.1(a) and (ii) the date
on which all waiting periods under the HSR Act applicable to the purchase of
Shares pursuant to Section 1 shall have expired or been terminated and (d) the
date that Parent or Sub shall have purchased the Shareholders' Shares pursuant
to Section 1.

          9. General Provisions.

          (a) Expenses. All costs and expenses incurred in connection with this
Agreement and the transactions contemplated hereby shall be paid by the party
incurring such expense.

          (b) Amendments. This Agreement may not be amended except by an
instrument in writing signed by each of the parties hereto.

          (c) Notice. All notices and other communications hereunder shall be in
writing and shall be deemed given upon receipt to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

         (i) if to Parent, to



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         Guidant Corporation
         111 Monument Circle
         Indianapolis, Indiana  46204-5129
         Attention:   J.B. King, Esq.

         with a copy to:

         Dewey Ballantine LLP
         1301 Avenue of the Americas
         New York, NY  10019-6092
         Fax: (212) 259-6333
         Attention:  Bernard E. Kury, Esq.
                     Jonathan L. Freedman, Esq.
         and

         (ii) if to a Shareholder, to the address set forth under the name of
such Shareholder on Schedule A hereto

         with a copy to:

         Perkins Coie LLP
         1201 Third Avenue, 40th Floor
         Seattle, Washington  98101-3099
         Fax: (206) 583-8500
         Attention:  Stephen M. Graham, Esq.
                     Alan C. Smith, Esq.

          (d) Interpretation. When a reference is made in this Agreement to a
Section, such reference shall be to a Section of this Agreement unless otherwise
indicated. The headings contained in this Agreement are for reference purposes
only and shall not affect in any way the meaning or interpretation of this
Agreement. Wherever the words "include", "includes" or "including" are used in
this Agreement, they shall be deemed to be followed by the words "without
limitation".

          (e) Counterparts. This Agreement may be executed in two or more
counterparts, all of which shall be considered one and the same agreement, it
being understood that all parties need not sign the same counterpart.

          (f) Entire Agreement; No Third-Party Beneficiaries. This Agreement
(including the documents and instruments referred to herein) (i) constitutes the
entire agreement and supersedes all prior agreements and understandings, both
written and oral, among the parties with respect to the subject matter hereof
and (ii) is not intended to confer upon any person other than the parties hereto
any rights or remedies hereunder.



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          (g) Governing Law. This Agreement shall be governed and construed in
accordance with the laws of the State of Delaware without regard to any
applicable conflicts of law.

          (h) Publicity. Except as otherwise required by law, court process or
the rules of a national securities exchange or the Nasdaq National Market or as
contemplated or provided in the Merger Agreement, for so long as this Agreement
is in effect, neither any Shareholder nor Parent shall issue or cause the
publication of any press release or other public announcement with respect to
the transactions contemplated by this Agreement or the Merger Agreement without
the consent of the other parties, which consent shall not be unreasonably
withheld.

          10. Shareholder Capacity. No person executing this Agreement who is or
becomes during the term hereof a director or officer of the Company makes any
agreement or understanding herein in his or her capacity as such director or
officer. Each Shareholder signs solely in his or her capacity as the record
holder and beneficial owner of, or the trustee of a trust whose beneficiaries
are the beneficial owners of, such Shareholder's Shares and nothing herein shall
limit or affect any actions taken by a Shareholder in its capacity as an officer
or director of the Company to the extent specifically permitted by the Merger
Agreement.

          11. Performance by Sub. Parent covenants and agrees for the benefit of
the Shareholders that it shall cause Sub to perform in full each obligation of
Sub set forth in this Agreement.

          12. Enforcement. The parties agree that irreparable damage would occur
in the event that any of the provisions of this Agreement were not performed in
accordance with their specific terms or were otherwise breached. It is
accordingly agreed that the parties shall be entitled to an injunction or
injunctions to prevent breaches of this Agreement and to enforce specifically
the terms and provisions of this Agreement in court of the United States located
in the State of Delaware or any Delaware State court, this being in addition to
any other remedy to which they are entitled at law or in equity. In addition,
each of the parties hereto waives any right to trial by jury with respect to any
claim or proceeding related to or arising out of this Agreement or any of the
transactions contemplated hereby.



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         IN WITNESS WHEREOF, each of Parent and Sub has caused this Agreement to
be signed by its officer thereunto duly authorized and each Shareholder has
signed this Agreement, all as of the date first written above.

                                            GUIDANT CORPORATION


                                            By: ________________________________
                                                Name:
                                                Title:

                                            PEGASUS ACQUISITIONS CORP.


                                            By: ________________________________
                                                Name:
                                                Title:

                                            SHAREHOLDER:


                                            [SHAREHOLDER]




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                                                                      SCHEDULE A



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