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EXECUTION COPY

AMENDMENT NO. 2
TO TRANSACTION AGREEMENT

        THIS AMENDMENT NO. 2 TO TRANSACTION AGREEMENT (this "Amendment"), dated
as of January 16, 2006, between BOSTON SCIENTIFIC CORPORATION, a Delaware
corporation ("Boston Scientific"), and ABBOTT LABORATORIES, an Illinois
corporation ("Abbott").

        WHEREAS, Boston Scientific and Abbott are parties to that certain
Transaction Agreement dated as of January 8, 2006 and amended as of January 16,
2006, pursuant to which Abbott agreed to acquire certain assets and businesses
and assume certain liabilities of Guidant contingent upon Boston Scientific's
acquisition of Guidant (the "Agreement"); and

        WHEREAS, Boston Scientific and Abbott desire to further amend the
Agreement as provided in this Amendment in accordance with Section 11.07 of the
Agreement.

        NOW, THEREFORE, in consideration of the foregoing and the promises and
mutual agreements contained in this Amendment, and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, and
intending to be legally bound, the parties hereto agree as follows:

SECTION 1. Amendment to the Agreement. The following new Article VI shall be
added to the Agreement, with the existing Articles VI through XI and Sections
within such articles being renumbered accordingly:

"ARTICLE VI SHARE PURCHASE

SECTION 6.01. Share Purchase. (a) At the Closing, Abbott shall purchase from
Boston Scientific, and Boston Scientific shall issue and sell to Abbott,
56,000,000 shares of common stock, par value $0.01 per share, of Boston
Scientific (the "Shares") at a purchase price of $25.00 per Share, for an
aggregate purchase price of $1,400,000,000 (the "Aggregate Stock Purchase
Price"); provided that if the average of the per share closing prices of Shares
on the New York Stock Exchange during the five consecutive trading days ending
(and including) the date that is three trading days prior to the date of the
Closing is less than $25.00, Abbott shall purchase from Boston Scientific, and
Boston Scientific shall issue and sell to Abbott, the number of Shares that is
equal to the quotient obtained by dividing $1,400,000,000 by such average per
share closing price (the per Share purchase price payable by Abbott or the
applicable Purchaser under this Section 6.01(a) being, the "Stock Purchase
Price"). In no event shall the number of Shares acquired by Abbott pursuant to
this Section 6.01(a) equal or exceed 5% of the number of Shares outstanding
immediately following the consummation of the Merger, and, in such event, the
Aggregate Stock Purchase Price shall be adjusted accordingly.

        (b)   At the Closing, (i) Abbott shall pay the aggregate Stock Purchase
Price by wire transfer of immediately available funds to a bank account
designated in writing by Boston Scientific to Abbott not fewer than three
Business Day prior to the date of the Closing, and (ii) Boston Scientific shall
deliver to Abbott stock certificates evidencing the Shares having the legend
described in Section 6.03.

SECTION 6.02. Sale Restrictions. (a) Neither Abbott nor any of its Affiliates
shall, directly or indirectly, sell, transfer, assign or otherwise dispose of
any Shares during the six-month period following the Closing; provided that if
the average of the per share closing prices of Shares on the New York Stock
Exchange during any consecutive twenty trading days during the six-month period
following the Closing is greater than $30.00, Abbott may sell Shares in
accordance with Section 6.03 during such six-month period. Neither Abbott nor
any of its Affiliates shall, directly or indirectly, during any one-month period
following the Closing, sell, transfer, assign or otherwise dispose of a number
of Shares that is greater than 8.33% of the Shares acquired by Abbott at the
Closing; provided, however, that such restrictions on the ability of Abbott or
any of its Affiliates to sell, transfer, assign or otherwise dispose of Shares
shall terminate on the date that is eighteen months following the date of the
Closing.

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The provisions of this Section 6.02(a) may be amended or waived at any time in
accordance with Section 12.07.

        (b)   Nothing in Section 6.02(a) shall prevent Abbott from selling any
of its Shares in any change of control transaction involving Boston Scientific
or from tendering its Shares into any tender offer for the Shares commenced by
Boston Scientific or any other Person.

SECTION 6.03. Registration Rights. (a) For purposes of this Section 6.03,
"Registrable Stock" means the Shares acquired by Abbott or the applicable
Purchaser pursuant to Section 6.01(a) or 6.05 as to which the Registration
Statement (as defined in Section 6.03(d)) has not become effective prior to the
date of the Closing, and any securities issued or issuable with respect to such
Shares by way of conversion, exchange, replacement, stock dividend, stock split
or other distribution or in connection with a combination of shares,
recapitalization, merger, consolidation or other reorganization or otherwise.
Any Registrable Stock shall cease to be Registrable Stock when (i) a
registration statement covering such Registrable Stock has been declared
effective and such Registrable Stock has been disposed of pursuant to such
effective registration statement, (ii) such Registrable Stock is sold by a
Person in a transaction in which the rights of Abbott under this Section 6.03
are not assigned, or (iii) such Registrable Stock is sold pursuant to
Rule 144(k) (or any similar provision then in force, but not Rule 144A) under
the Securities Act of 1933, as amended (the "Securities Act") without
registration under the Securities Act.

        (b)   Each certificate representing shares of Registrable Stock shall,
except as otherwise provided in this Section 6.03, be stamped or otherwise
imprinted with legends substantially in the following form:

        (i)    "THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
THE RESTRICTIONS ON DISPOSITION OF A TRANSACTION AGREEMENT DATED AS OF JANUARY
8, 2006, AS AMENDED, BETWEEN ABBOTT LABORATORIES AND BOSTON SCIENTIFIC
CORPORATION."; and

        (ii)   "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 AND MAY NOT BE TRANSFERRED OR
OTHERWISE DISPOSED OF UNLESS THEY HAVE BEEN REGISTERED UNDER THAT ACT OR AN
EXEMPTION FROM REGISTRATION IS AVAILABLE."

Each certificate representing Shares acquired by Abbott pursuant to this
Agreement and covered by the Registration Statement shall, except as otherwise
provided in this Section 6.03, be stamped or otherwise imprinted with a legend
substantially in the form set forth in clause (i) of this Section 6.03(b).

        (c)   Boston Scientific shall, at the request of Abbott, (i) remove from
each certificate evidencing Shares the legend described in Section 6.03(b)(i) at
such time as Abbott and its Affiliates own fewer than 8.33% of the Shares
acquired by Abbott at the Closing, and (ii) remove from each certificate
evidencing Registrable Stock the legend described in Section 6.03(b)(ii) if in
the opinion of counsel satisfactory to Boston Scientific Registrable Stock
evidenced thereby may be publicly sold without registration under the Securities
Act. Boston Scientific shall reasonably cooperate with Abbott to remove the
legends described in Section 6.03(b) so as to allow Abbott or its Affiliates to
sell, transfer, assign or otherwise dispose of Shares as permitted by
Section 6.02.

        (d)   Boston Scientific shall use its reasonable best efforts to file
with, and have declared effective by, the Securities and Exchange Commission
(the "SEC") on or prior to the date of the Closing a registration statement on
Form S-3 under the Securities Act (the "Registration Statement") with respect to
the issuance of the Shares issuable by Boston Scientific to Abbott pursuant to
this Agreement. To the extent such issuance has not been registered pursuant to
an effective Registration Statement on or prior to the date of Closing despite
the use by Boston Scientific of such efforts, Boston Scientific shall, as
promptly as practicable on or following the date of the Closing, file with the
SEC a "shelf" registration statement on Form S-3 pursuant to Rule 415 under the
Securities Act (the "Shelf Registration") with respect to the Shares issuable by
Boston Scientific to Abbott pursuant to this

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Agreement, and thereafter shall use its reasonable best efforts to (i) have the
Shelf Registration declared effective as soon as reasonably practicable
thereafter, and (ii) keep the Shelf Registration continuously effective from the
date such Shelf Registration is declared effective until at least the second
anniversary of such effective date (the "Effectiveness Period") in order to
permit the prospectus forming a part thereof to be usable by Abbott and its
Affiliates during such period. Boston Scientific shall use its reasonable best
efforts to list the Shares issuable by Boston Scientific to Abbott pursuant to
this Agreement on the New York Stock Exchange.

        (e)   Notwithstanding anything to the contrary contained herein, Boston
Scientific shall have the right to defer or delay filing the Shelf Registration
for a period of not more than 60 days, or suspend sales under the Shelf
Registration filed hereunder or defer the updating of such filed Shelf
Registration during no more than two periods aggregating not more than 60 days,
in the event that Boston Scientific furnishes to Abbott a certificate signed by
an authorized officer of Boston Scientific stating that, in the good faith
opinion of the Board of Directors of Boston Scientific, such filing, sale or
update would interfere with any material transaction then being pursued by
Boston Scientific or would otherwise require disclosure of any material event
that Boston Scientific would not otherwise be required to disclose; provided,
however, that Boston Scientific shall extend the Effectiveness Period by the
number of days, if any, during with the registration rights contemplated
hereunder are subject to a deferral or suspension as set forth in this
Section 6.03(e).

        (f)    Subject to Section 6.03(e), if Boston Scientific files a Shelf
Registration pursuant to Section 6.03(d), Boston Scientific shall, as promptly
as practicable:

        (i)    supplement or amend the Shelf Registration and the prospectus
used in connection therewith (i) as required by the registration form utilized
by Boston Scientific or by the instructions applicable to such registration form
or by the Securities Act, and (ii) to include in such Shelf Registration any
additional securities that become Registrable Stock by operation of the
definition thereof;

        (ii)   furnish to Abbott such numbers of copies of the Shelf
Registration and the prospectus included therein, including each preliminary
prospectus and any amendments or supplements thereto in conformity with the
requirements of the Securities Act, any exhibits filed therewith and such other
documents and information as Abbott may reasonably request;

        (iii)  use all reasonable best efforts to register or qualify the
Registrable Stock covered by the Shelf Registration under such other securities
or Blue Sky Laws of such jurisdiction within the United States as shall be
reasonably appropriate for the distribution of the Registrable Stock covered by
the Shelf Registration; provided, however, that Boston Scientific shall not be
required in connection therewith or as a condition thereto to qualify to do
business in or to file a general consent to service of process in any
jurisdiction wherein it would not but for the requirements of this
paragraph 6.03(f)(iii) be obligated to do so; and provided further, that Boston
Scientific shall not be required to qualify such Registrable Stock in any
jurisdiction in which the securities regulatory authority requires that Abbott
or any of its Affiliates submit any Registrable Stock to the terms, provisions
and restrictions of any escrow, lockup or similar agreement(s) for consent to
sell Registrable Stock in such jurisdiction unless Abbott or such Affiliate
agrees to do so;

        (iv)  promptly notify Abbott upon becoming aware of the happening of any
event as a result of which the prospectus included in such Shelf Registration,
as then in effect, includes an untrue statement of a material fact or omits to
state any material fact required to be stated therein or necessary to make the
statements therein not misleading in light of the circumstances under which they
were made, and, at the request of Abbott, promptly prepare and furnish to Abbott
a reasonable number of copies of a supplement to or an amendment of such
prospectus as may be necessary so that, as thereafter delivered to the
purchasers of such securities, such prospectus shall not include an untrue
statement of a material fact or omit to state a material fact required to be

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stated therein or necessary to make the statements therein not misleading in
light of the circumstances under which they were made. In the event Boston
Scientific shall give such notice, Boston Scientific shall extend the
Effectiveness Period by the number of days during the period from and including
the date of the giving of such notice to the date when Boston Scientific shall
make available to Abbott such supplemented or amended prospectus; and

        (v)   enter into customary agreements and take such other actions as are
reasonably required in order to expedite or facilitate the disposition of the
Registrable Stock to be so included in the Shelf Registration.

        (g)   It shall be a condition precedent to the obligations of Boston
Scientific to take any action pursuant to this Section 6.03 that Abbott and its
Affiliates shall furnish to Boston Scientific such information regarding
themselves, the Registrable Stock held by them, and the intended method of
disposition of such securities as Boston Scientific shall reasonably request and
as shall be required in connection with the action to be taken by Boston
Scientific hereunder.

        (h)   All expenses incurred in connection with the Registration
Statement and Shelf Registration, if any, excluding underwriters' discounts and
commissions, but including all registration, filing and qualification fees, word
processing, duplicating, printers' and accounting fees, listing fees, messenger
and delivery expenses, all fees and expenses of complying with state securities
or blue sky laws, and the fees and disbursements of counsel for Boston
Scientific, shall be paid by Boston Scientific. Abbott shall bear and pay the
underwriting commissions and discounts applicable to Registrable Stock offered
for its account and the fees and disbursements of its counsel in connection with
any registrations, filings and qualifications made pursuant to this Agreement.

        (i)    Boston Scientific shall indemnify and hold harmless Abbott and
its Affiliates, officers and directors against any losses, claims, damages or
liabilities, joint or several, to which they may become subject under the
Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or proceedings in respect thereof) arise out of or are based on any
untrue or alleged untrue statement of any material fact contained in the
Registration Statement or the Shelf Registration, as applicable, on the
effective date thereof (including any prospectus filed under Rule 424 under the
Securities Act, or any amendments or supplements thereto) or arise out of or are
based upon the omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, and shall reimburse Abbott and its Affiliates, officers and
directors for any legal or other expenses reasonably incurred by them (but not
in excess of expenses incurred in respect of one counsel for all of them) in
connection with investigating or defending any such loss, claim, damage,
liability or action; provided, however, that the indemnity agreement contained
in this Section 6.03(i) shall not apply to amounts paid in settlement of any
such loss, claim, damage, liability or action if such settlement is effected
without the consent of Boston Scientific (which consent shall not be
unreasonably withheld); provided, further, that Boston Scientific shall not be
liable to Abbott or its Affiliates, officers or directors in any such case for
any such loss, claim, damage, liability or action to the extent that it arises
out of or is based upon an untrue statement or alleged untrue statement or
omission or alleged omission made in connection with such Registration
Statement, Shelf Registration, preliminary prospectus, final prospectus or
amendments or supplements thereto, in reliance upon and in conformity with
written information furnished expressly for use in connection with such
registration by Abbott or any of its Affiliates, officers or directors. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of Abbott or any of its Affiliates, officers or directors.

        (j)    Abbott shall indemnify and hold harmless Boston Scientific, its
Affiliates, officers and directors and each agent and any underwriter for Boston
Scientific (within the meaning of the Securities Act) against any losses,
claims, damages or liabilities, joint or several, to which Boston Scientific or
any such Affiliate, officer, director, agent or underwriter may become subject,
under the

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Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or proceedings in respect thereof) arise out of or are based upon
any untrue statement or alleged untrue statement of any material fact contained
in the Registration Statement or Shelf Registration, as applicable, on the
effective date thereof (including any prospectus filed under Rule 424 under the
Securities Act or any amendments or supplements thereto) or arise out of or are
based upon the omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, in each case to the extent that such untrue statement or alleged
untrue statement or omission or alleged omission was made in such Registration
Statement, Shelf Registration, preliminary or final prospectus, or amendments or
supplements thereto, in reliance upon and in conformity with written information
furnished by or on behalf of Abbott or any of its Affiliates expressly for use
in connection with such registration; and Abbott shall reimburse any legal or
other expenses reasonably incurred by Boston Scientific or any such Affiliate,
officer, director, agent or underwriter in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the indemnity agreement contained in this Section 6.03(j) shall not apply
to amounts paid in settlement of any such loss, claim, damage, liability or
action if such settlement is effected without the consent of Abbott (which
consent shall not be unreasonably withheld). Such indemnity shall remain in full
force and effect regardless of any investigation made by or on behalf of Boston
Scientific or any of its Affiliates, officers or directors.

        (k)   Promptly after receipt by an indemnified party under
Section 6.03(i) or (j), as applicable, of notice of the commencement of any
action, such indemnified party shall, if a claim in respect thereof is to be
made against any indemnifying party under Section 6.03(i) or (j), as applicable,
notify the indemnifying party in writing of the commencement thereof, and the
indemnifying party shall have the right to participate in and assume the defense
thereof with counsel selected by the indemnifying party and reasonably
satisfactory to the indemnified party (unless (i) such indemnified party
reasonably objects to such assumption on the grounds that there may be defenses
available to it which are different from or in addition to those available to
such indemnifying party, (ii) the indemnifying party and such indemnified party
shall have mutually agreed to the retention of such counsel or (iii) in the
reasonable opinion of such indemnified party, representation of such indemnified
party by the counsel retained by the indemnifying party would be inappropriate
due to actual or potential differing interests between such indemnified party
and any other party represented by such counsel in such proceeding, in which
case the indemnified party shall be reimbursed by the indemnifying party for the
reasonable expenses incurred in connection with retaining separate legal
counsel); provided, however, that an indemnified party shall have the right to
retain its own counsel, with all fees and expenses thereof to be paid by such
indemnified party, and to be apprised of all progress in any proceeding the
defense of which has been assumed by the indemnifying party, it being understood
that the indemnifying party will control such defense. The failure to notify an
indemnifying party promptly of the commencement of any such action shall not
relieve the indemnifying party from any liability in respect of such action
which it may have to such indemnified party on account of the indemnity
contained in Section 6.03(i) or (j), as applicable, unless (and only to the
extent) the indemnifying party was prejudiced by such failure, and in no event
shall such failure relieve the indemnifying party from any other liability which
it may have to such indemnified party. No indemnifying party shall, without the
prior written consent of the indemnified party (which consent will not be
unreasonably withheld), effect any settlement, compromise or discharge of any
claim or pending or threatened proceeding in respect of which the indemnified
party is or could have been a party and indemnity could have been sought
hereunder by such indemnified party, unless such settlement, compromise or
discharge includes an unconditional release of such indemnified party from all
liability arising out of such claim or proceeding.

        (l)    To the extent any indemnification by an indemnifying party is
prohibited or limited by Law, the indemnifying party, in lieu of indemnifying
such indemnified party, shall contribute to the amount paid or payable by such
indemnified party as a result of such losses, claims, damages or liabilities in

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such proportion as is appropriate to reflect the relative fault of the
indemnifying party and indemnified party in connection with the actions which
resulted in such losses, claims, damages or liabilities, as well as any other
relevant equitable considerations. The relative fault of such indemnifying party
and indemnified party shall be determined by reference to, among other things,
whether any action in question, including any untrue or alleged untrue statement
of material fact or omission or alleged omission to state a material fact, has
been made by, or relates to information supplied by, such indemnifying party or
indemnified party, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such action. The amount paid
or payable by a party as a result of the losses, claims, damages or liabilities
referred to above shall be deemed to include any legal or other fees or expenses
reasonably incurred by such party in connection with any investigation or
proceeding. In no event shall the liability of any indemnifying party be greater
in amount than the amount for which such indemnifying party would have been
obligated to pay by way of indemnification if the indemnification provided for
under Section 6.03(i) or (j) hereof had been available under the circumstances.
The parties hereto agree that it would not be just and equitable if contribution
pursuant to this Section 6.03(l) were determined by pro rata allocation or by
any other method of allocation which does not take account of the equitable
considerations referred to in this Section 6.03(l). No person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the
Securities Act) shall be entitled to contribution from any person who was not
guilty of such fraudulent misrepresentation.

SECTION 6.04. Loan Prepayment. If, at any time during the term of the loan
described in Section 5.10, Abbott or any of its Affiliates sells any Shares,
then Abbott and Boston Scientific shall share in the proceeds per share (net of
any underwriting discounts and commissions) (the "Net Proceeds") as follows:
(a) if the Net Proceeds to Abbott or such Affiliates from any such sales are
less than or equal to 110% of the Stock Purchase Price, Abbott shall retain all
of such Net Proceeds, (b) if the Net Proceeds to Abbott or such Affiliates from
any such sales are greater than 110% but equal to or less than 120% of the Stock
Purchase Price, Abbott shall retain the portion of the Net Proceeds equal to
110% of the Stock Purchase Price, and the portion of the Net Proceeds in excess
of 110% of the Stock Purchase Price (net of Taxes) shall be immediately applied
by Abbott to prepay any amounts then outstanding under the loan in accordance
with Section 5.10(b), and (c) if the Net Proceeds to Abbott or such Affiliates
from any such sales are greater than 120% of the Stock Purchase Price, Abbott
shall retain the portion of the Net Proceeds equal to 110% of the Stock Purchase
Price, the portion of the Net Proceeds in excess of 110% but less than or equal
to 120% of the Stock Purchase Price (net of Taxes) shall be immediately applied
by Abbott to prepay any amounts then outstanding under the loan in accordance
with Section 5.10(b), and, with respect to all Net Proceeds in excess of 120% of
the Stock Purchase Price, 50% of such excess amount shall be retained by Abbott,
and the remaining 50% (net of Taxes) shall be immediately applied by Abbott to
prepay any amounts then outstanding under the loan in accordance with
Section 5.10(b). Abbott shall notify Boston Scientific in writing within three
Business Days of any such sales of Shares by it or any of its Affiliates, and
shall include in such notice the number of Shares sold by it or such Affiliates,
the selling price for such Shares, and the amount of Taxes payable by Abbott or
such Affiliates with respect to such sales, and shall give a third party
designated by Boston Scientific and reasonably acceptable to Abbott reasonable
access to the books and records of Abbott for purposes of verifying such
information.

SECTION 6.05. Interest Reimbursement. On the date that is eighteen months
following the Closing Date, Boston Scientific shall issue to Abbott a number of
Shares that is equal to the quotient obtained by dividing the Cost of Borrowing
(as defined below) by the average of the per share closing prices of Shares on
the New York Stock Exchange during the twenty consecutive trading days ending
(and including) the date that is five trading days prior to such date. For
purposes of this Section 6.05, the "Cost of Borrowing" means Abbott's actual
cost of borrowing incurred during the period commencing on the date of the
Closing and ending on the eighteen month anniversary of the Closing of the funds
used by it or the applicable Purchaser to pay the Aggregate Stock Purchase
Price; provided that Boston

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Scientific will only be required to reimburse Abbott pursuant to this
Section 6.05 with respect to any Cost of Borrowing greater than $10 million and
less than or equal to $70 million; provided further that, for purposes of
calculating the Cost of Borrowing, the Net Proceeds to Abbott or any of its
Affiliates from sales of Shares that are retained by Abbott as described in
Section 6.04 shall be deemed to have been applied by Abbott (net of Taxes) to
reduce the amount of Abbott's borrowing in respect of the Aggregate Stock
Purchase Price. Nothing contained in this Section 6.05 shall require Abbott to
make any actual payment with respect to such borrowing. Abbott shall notify
Boston Scientific in writing on a quarterly basis following the Closing of its
Cost of Borrowing during the immediately preceding quarter, which Cost of
Borrowing shall be subject to audit by a third party designated by Boston
Scientific and reasonably acceptable to Abbott. Any Shares issued by Boston
Scientific pursuant to this Section 6.05 shall bear the legend described in
Section 6.03(b)(ii), which shall be removed at the request of Abbott in
accordance with Section 6.03(c)(ii)."

SECTION 2. Public Announcement. The provisions contained in Section 12.03 of the
Agreement are incorporated by reference in this Amendment as though they were
expressly set forth herein.

SECTION 3. Representations and Warranties. (a) Boston Scientific represents and
warrants to Abbott as follows:

        (i)    Boston Scientific is a corporation duly incorporated, validly
existing and in good standing under the Laws of the State of Delaware and has
all necessary corporate power and authority to enter into, execute and deliver
this Amendment, to carry out its obligations hereunder and to consummate the
transactions contemplated hereby. The execution and delivery of this Amendment
by Boston Scientific, the performance by Boston Scientific of its obligations
hereunder and the consummation by Boston Scientific of the transactions
contemplated hereby have been duly authorized by all requisite corporate action
on the part of Boston Scientific. This Amendment has been duly executed and
delivered by Boston Scientific, and, assuming due authorization, execution and
delivery by Abbott, this Amendment is a legal, valid and binding obligation of
Boston Scientific, enforceable against it in accordance with its terms.

        (ii)   All Shares issued pursuant to Sections 6.01 and 6.05 shall, when
issued, be validly issued, fully paid and nonassessable, and shall be free and
clear of any liens, claims, charges and encumbrances other than those imposed as
a result of any action by Abbott or any of its Affiliates.

        (b)   Abbott represents and warrants to Boston Scientific as follows:
Abbott is a corporation duly incorporated, validly existing and in good standing
under the laws of the State of Illinois and has all necessary corporate power
and authority to enter into, execute and deliver this Amendment, to carry out
its obligations hereunder and to consummate the transactions contemplated
hereby. The execution and delivery of this Amendment by Abbott, the performance
by Abbott of its obligations hereunder and the consummation by Abbott of the
transactions contemplated hereby have been duly authorized by all requisite
corporate action on the part of Abbott. This Amendment has been duly executed
and delivered by Abbott, and, assuming due authorization, execution and delivery
by Boston Scientific, this Amendment is a legal, valid and binding obligation of
Abbott enforceable against it in accordance with its terms.

SECTION 4. Ratification of Agreement. Except as expressly provided in this
Amendment, all of the terms, covenants, and other provisions of the Agreement
are hereby ratified and confirmed and shall continue to be in full force and
effect in accordance with their respective terms. From and after the date
hereof, all references to the Agreement shall refer to the Agreement as amended
by this Amendment. Capitalized terms used but not defined in this Amendment
shall have the meanings assigned to them in the Agreement.

SECTION 5. Governing Law. This Amendment shall be governed by, and construed in
accordance with, the laws of the State of New York. All Actions arising out of
or relating to this Amendment shall be

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heard and determined exclusively in any New York federal court sitting in the
Borough of Manhattan of The City of New York.

SECTION 6. Counterparts. This Amendment may be executed and delivered (including
by facsimile transmission) in one or more counterparts, and by the different
parties hereto in separate counterparts, each of which when executed shall be
deemed to be an original, but all of which taken together shall constitute one
and the same agreement.

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        IN WITNESS WHEREOF, Boston Scientific and Abbott have caused this
Amendment to be executed as of the date first written above by their respective
officers thereunto duly authorized.

    BOSTON SCIENTIFIC CORPORATION
 
 
By:
 
         

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    Name:   Lawrence C. Best     Title:   Executive Vice President, Chief
Financial Officer
 
 
ABBOTT LABORATORIES
 
 
By:
 
         

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    Name:   Richard A. Gonzalez     Title:   President and Chief Operating
Officer, Medical Products Group

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AMENDMENT NO. 2 TO TRANSACTION AGREEMENT