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                                                                    Exhibit 14.1


                                   DYAX CORP.

                       CODE OF BUSINESS CONDUCT AND ETHICS

         This Code of Business Conduct and Ethics sets forth legal and ethical
standards of conduct for personnel of Dyax Corp. and its subsidiaries
(collectively, the "Company"). This Code applies generally to all the Company's
directors, officers1 and employees and is addressed to them directly.

         We are committed to adhering to applicable legal requirements and
maintaining the highest standards of conduct and integrity. This Code is
intended to promote those goals in conjunction with the Company's Insider
Trading Policy, Disclosure Policy and Practices and Audit Committee Complaint
Procedures (the "Policies").

         Because a written code cannot answer all questions raised in the
context of business relationships, you (namely any employee, officer or director
of Dyax) must take responsibility for recognizing and responding appropriately
to specific situations as they arise. If you have any question about the
requirements of this Code or the appropriateness of a relationship or action,
you should consult with your supervisor or the Senior Vice President, Legal
Affairs; or in the case of a director or officer, the Chief Executive Officer or
the Chair or any other disinterested member of the Nominating and Governance
Committee charged with administering this Code.

         Please also note that the restrictions on conflicts of interest and the
receipt of improper benefits also apply to your family members, dependents and
affiliated persons. You are responsible for any conflicts that may arise for you
due to their conduct and for the consequences to you of any improper benefits
that they may receive.

         You should report suspected violations of this Code promptly as
outlined under the heading "Reporting and Compliance Procedures" below.

         COMPLIANCE WITH LAWS AND REGULATIONS. All employees, officers and
directors must comply with, and must endeavor to ensure the Company complies
with, all laws and regulations applicable to the Company wherever it does
business, as well as the listing standards of any exchange on which the
Company's securities are traded. You are expected to use good judgment and
common sense in seeking to comply and to ask for advice when you are uncertain
about what is required.

         CONFLICTS OF INTEREST. Personal interests and relationships must not
harm the Company's interests. Any actual or apparent conflict of interest
between personal interests and those of the Company must be handled honestly and
ethically in accordance with the following procedures. Any conflict of interest
is prohibited unless it has gone through the process of disclosure, consultation
and approval set forth below.

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(1) Nasdaq has confirmed orally that "officer" has the meaning set forth in Rule
16a-1(f) under the Securities Exchange Act of 1934, which is very close to the
definition of "executive officer" used elsewhere in that Act. Thus any Section
16 reporting officer should be treated as an "officer" for purposes of this
Code.

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         FULL DISCLOSURE IS THE ESSENTIAL FIRST STEP to remaining in full
compliance with this policy. You must disclose any actual or reasonably apparent
conflict of interest, including any existing or proposed transaction or
relationship that reasonably could be expected to give rise to a conflict of
interest. An employee must disclose such matters to his/her supervisor (or, if
that person is involved in the matter, to the Senior Vice President, Legal
Affairs), who is responsible for consulting with the Chief Executive Officer or
Chair of the Nominating and Governance Committee, as appropriate. Officers and
directors must disclose such matters to the Chief Executive Officer and to the
Chair or any other disinterested member of the Nominating and Governance
Committee charged with reviewing conflicts of interest.

         The Board of Directors has adopted rules for what activities constitute
conflicts of interest and potential conflicts of interests, as well as
procedures for determining whether a relationship or transaction constitutes a
conflict of interest, which it will review and, if appropriate, update from time
to time. The current version of these rules and procedures are attached as
APPENDICES A and B to this Code and are available on the Company's website at
www.dyax.com.

         Following disclosure, any employee, officer or director must avoid or
terminate any activity that involves an actual or reasonably apparent conflict
of interest unless it is determined at the appropriate level that the activity
is not a conflict of interest or is otherwise not harmful to the Company or
improper. Any such determination shall be made by the Chief Executive Officer in
the case of an employee, and by the disinterested members of the Nominating and
Governance Committee in the case of an officer or director.

         No director, director nominee, officer, or greater than 5% shareholder
may enter into any transaction or relationship that is disclosable by the
Company pursuant to SEC Reg. S-K, Item 404 without the prior approval of the
Chair of the Nominating and Governance Committee. Nor may any director, officer
or employee directly or indirectly approve, or represent the Company or the
other party in arranging, the terms of any transaction between the Company and a
party with which he/she has any relationship of a type that is disclosable by
the Company pursuant to SEC Reg. S-K, Item 404. All transactions between the
Company and a party with which a director, officer or employee has such a
relationship shall be on an arm's-length basis. Details about this prohibition
may be obtained from the Senior Vice President, Legal Affairs.

         CONFIDENTIALITY. You must maintain the confidentiality of confidential
and personal information entrusted to you by the Company, its customers or other
companies, including our suppliers. Any use or public disclosure of any such
information is prohibited except as authorized in the conduct of Company
business or otherwise legally mandated. You should also take appropriate
precautions to ensure that such confidential information is not communicated
within the Company except to personnel who have a need to know such information
to perform their responsibilities for the Company.

         GIFTS, GRATUITIES AND BUSINESS ENTERTAINMENT. All employees, officers
and directors must conduct their affairs in such a manner as to avoid adversely
affecting their judgment or the Company's reputation.

         ACCEPTANCE OF GIFTS OR ENTERTAINMENT. No one shall accept any gift or
other benefit that reasonably appears to be given in exchange, or as a reward,
for any accommodation in

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connection with soliciting, negotiating or maintaining a business relationship
for the Company. The following may usually be accepted without violating this
rule:

         -  Modest, conventional business entertainment.

         -  Modest gifts offered on account of a family or personal relationship
            or as a token of appreciation upon a holiday or commonly recognized
            personal event, such as a wedding or promotion.

         -  Items that would be paid for by the Company as a reasonable business
            expense if not paid for by another party.

         -  Benefits available to the general public on the same terms.

However, the actual circumstances may raise concerns, so one must be vigilant.
Any exceptions to this rule must be pre-approved by the Senior Vice President,
Legal Affairs and documented.

         The Chief Executive Officer or the Chair of the Nominating and
Governance Committee shall have the authority to require that any gift be
returned or entertainment be declined if determined not to be in the best
interests of the Company.

         BRIBERY. Bribery is a criminal act. No Company personnel may offer or
give any form of bribe or kickback to any government official or other person in
order to secure preferential treatment in connection with Company business.
Modest, conventional business entertainment or promotional materials complying
with Company guidelines that are not intended to secure preferential treatment
are generally acceptable; however, no meal, entertainment or gift exceeding $50
in value may be provided to any government official or any employee of a
governmental agency without the approval of the Senior Vice President, Legal
Affairs, or, in the case of any officer or director, the Chair of the Nominating
and Governance Committee.

         Bona fide inducements in the form of business terms must be reasonably
related to the value to be received by the Company, competitively justified,
authorized in accordance with Company guidelines and properly documented. They
may be provided only to the party with which the Company has the business
relationship and not directly or indirectly to any individual officer, employee
or other agent of such party.

         FOREIGN CORRUPT PRACTICES ACT. All officers, directors, employees,
agents and stockholders acting on behalf of the Company must comply with the
anti-bribery, accounting and recordkeeping provisions of the Foreign Corrupt
Practices Act (the "FCPA"). The FCPA prohibits the Company and anyone acting on
its behalf from directly or indirectly making, offering to make, promising to
make or approving a payment of money or anything else of value to a foreign
official or a foreign political party with the intention of somehow influencing
that official to assist the Company in obtaining or retaining business. The
civil and criminal penalties that the FCPA imposes on individual and corporate
violators are severe. When in doubt as to whether a contemplated payment or gift
may violate the FCPA, consult with the Senior Vice President, Legal Affairs
before taking any action.

         FAIR DEALING. Each employee, officer and director should endeavor to
deal honestly, ethically and fairly with the Company's suppliers, customers,
competitors and employees. Your

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statements about the Company's products and services should not be untrue or
misleading. You should not take unfair advantage of anyone through manipulation,
concealment, abuse of privileged information, misrepresentation of material
facts or any other unfair practice.

         PROTECTION OF COMPANY ASSETS AND OPPORTUNITIES. All personnel should
seek to protect the Company's assets. You may not take personal advantage of
opportunities that are discovered through your position with the Company. All
transactions on behalf of the Company and all uses of Company funds, facilities
or other assets must be solely for business purposes of the Company, pursuant to
due authorization, and properly documented.

         ACCURACY OF BOOKS, RECORDS AND REPORTS. All Company books, records and
accounts shall be maintained in accordance with all applicable regulations and
standards and accurately reflect the true nature of the transactions they
record. You are responsible for the accuracy of your records and reports. No
undisclosed or unrecorded account or fund shall be established for any purpose.

         INTERNAL CONTROLS; DISCLOSURE CONTROLS AND PROCEDURES. It is the
responsibility of the Chief Executive Officer, the Chief Financial Officer, and
the other executive and financial officers to ensure that the Company maintains
(i) adequate controls over its assets and financial reporting and (ii) adequate
controls and procedures to provide full, fair, accurate, timely and
understandable disclosure in reports and documents filed with, or submitted to,
regulatory authorities and in other public communications.

         You should promptly bring to the attention of the Chair or other member
of the Audit Committee any information you may have (i) concerning deficiencies
in the design or operation of internal controls that could adversely affect the
Company's ability to record, process, summarize and report financial data, (ii)
concerning any fraud affecting the Company, or (c) that otherwise affects the
disclosures made by the Company in its regulatory filings and other public
communications.

         WAIVERS OF THIS CODE OF BUSINESS CONDUCT AND ETHICS. While some of the
policies contained in this Code must be strictly adhered to and no exceptions
can be allowed, in other cases exceptions may be possible. Any employee who
believes that an exception to any of these policies is appropriate in his or her
case should first contact his or her immediate supervisor. If the supervisor
agrees that an exception is appropriate, the approval of the Chief Executive
Officer must be obtained after consultation with the Senior Vice President,
Legal Affairs. Any officer or director who seeks an exception to any of these
policies should contact the Chief Executive Officer or the Chair or another
disinterested member of the Nominating and Governance Committee charged with
administering this Code. Any waiver of this Code for an officer or director may
be made only by the disinterested members of the Board of Directors and shall be
publicly disclosed as required by applicable law or otherwise.

         REPORTING AND COMPLIANCE PROCEDURES. Every employee, officer and
director has the responsibility to ask questions, seek guidance, report
suspected violations and express concerns regarding compliance with this Code or
any of the Company's other Policies. Anyone who believes that any other
employee, officer or director has engaged or is engaging in conduct that
violates applicable law or this Code should promptly report such information to
the Senior Vice President, Legal Affairs or the Chair of the Nominating and
Governance Committee. You may

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report such conduct anonymously, including through the Company's website at
Www.dyax.com; however, there may be circumstances when the Company is obligated
to divulge your identity.

         THE COMPANY WILL NOT DISCIPLINE, DISCRIMINATE AGAINST OR RETALIATE
AGAINST ANY PERSON WHO REPORTS SUCH CONDUCT IN GOOD FAITH OR WHO COOPERATES IN
ANY INVESTIGATION OR INQUIRY REGARDING SUCH CONDUCT.

         The Senior Vice President, Legal Affairs of the Company shall maintain
written records of all reports of material violations of this Code and the
resolution thereof and of all waivers granted under this Code.

         The Company shall make this Code publicly available on its website.

         The Nominating and Governance Committee shall monitor and periodically
evaluate compliance with this Code and its application to the Company's
business. The Board of Directors may amend this Code on the recommendation of
the Committee or on its own motion.

         ACCOUNTABILITY FOR VIOLATIONS OF THE CODE. Failure to comply with the
standards required by this Code or any of the Company's other Policies will
result in disciplinary action that may include, without limitation, reprimands,
warnings, probation or suspension without pay, demotions, reductions in salary,
discharge or removal, and restitution. Certain violations may be referred to
public authorities for investigation or prosecution. Moreover, any supervisor
who directs or approves of any conduct in violation of this Code or any Policy,
or who has knowledge of such conduct and does not promptly report it, also will
be subject to disciplinary action, up to and including discharge.

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                                   APPENDIX A

                           CONFLICTS OF INTEREST RULES

1.       IMPROPER CONFLICTS OF INTEREST

         The Board of Directors has adopted the following rules to aid in
determining whether a relationship or transaction constitutes a conflict of
interest. The Board has determined that the following involve an improper
conflict of interest under the Company's Code of Business Conduct and Ethics.
This list is not exhaustive and is subject to review and revision by the Board
from time to time.

         EMPLOYEES AND OFFICERS.  An employee or officer must not:

         (a)   perform services as an employee, officer, director, advisor,
consultant (directly or through an entity) or in any other capacity for a
significant customer, significant supplier or direct competitor of the Company,
other than at the request, or with the prior approval, of the Company;

         (b)   have a financial interest in a significant supplier or
significant customer of the Company, other than an investment representing less
than one percent (1%) of the voting power of a publicly-held company or less
than five percent (5%) of the voting power of a privately-held company; or

         (c)   have a financial interest in a direct competitor of the Company,
other than an investment representing less than one percent (1%) of the voting
power of a publicly-held company.

         NON-EMPLOYEE DIRECTORS.  A non-employee director must not:

         (a)   perform services as an employee, officer, director, advisor,
consultant (directly or through an entity) or in any other capacity for a direct
competitor of the Company;

         (b)   have, or permit any close relative to have, a financial interest
in a direct competitor of the Company, other than an investment representing
less than one percent (1%) of the outstanding shares of a publicly-held company;

         (c)   use his or her position with the Company to influence any
decision of the Company relating to a contract or transaction with a supplier or
customer of the Company if the director or a close relative of the director:

         -  performs services as an employee, officer, director, advisor,
            consultant (directly or through an entity) or in any other capacity
            for such supplier or customer; or

         -  has a financial interest in such supplier or customer, other than an
            investment representing less than one percent (1%) of the
            outstanding shares of a publicly-held company; or

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         (d)   induce or otherwise assist or participate, directly or
indirectly, in a close relative's involvement with or investment in a
significant supplier, significant customer or direct competitor of the Company
in a manner that would be prohibited for the employee or officer under any of
the prohibited activities listed above.

         A "CLOSE RELATIVE" of a person includes a spouse, parent, sibling,
child, mother- or father-in-law, son- or daughter-in-law or brother- or
sister-in-law, and any other relative living in the same home with the person. A
"SIGNIFICANT CUSTOMER" is a customer that has made during the Company's last
full fiscal year, or proposes to make during the Company's current fiscal year,
payments to the Company for property or services in excess of 5% of (i) the
Company's consolidated gross revenues for its last full fiscal year or (ii) the
customer's consolidated gross revenues for its last full fiscal year. A
"SIGNIFICANT SUPPLIER" is a supplier to which the Company has made during the
Company's last full fiscal year, or proposes to make during the Company's
current fiscal year, payments for property or services in excess of 5% of (i)
the Company's consolidated gross revenues for its last full fiscal year or (ii)
the customer's consolidated gross revenues for its last full fiscal year.

     2.  POTENTIAL CONFLICTS OF INTEREST REQUIRING DISCLOSURE

The Board of Directors has determined that the following involve potential
conflicts of interest that must be disclosed under the Company's Code of
Business Conduct and Ethics and then addressed in any manner determined in
accordance with the procedures thereunder:

         -  An employee, officer or director has a close relative who serves as
            an officer or director of a significant supplier, significant
            customer or direct competitor of the Company and such service would
            have been prohibited if the employee, officer or director were
            serving in that role under Section 1 of these rules.

         -  Any other material financial interest of an employee, officer or
            director in connection with any business relationship with the
            Company or any similar interest of a close relative of any of them
            that is known to the related employee, officer or director.

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                                   APPENDIX B

          PROCEDURES FOR DETERMINING CONFLICTS OF INTEREST AND WAIVERS

         In determining whether a conflict of interest exists and whether to
waive a Code of Business Conduct and Ethics provision in a particular
circumstance, the appropriate officer or the Nominating and Governance
Committee, as the may be, should also consider:

         -  THE PERSON INVOLVED IN THE POTENTIAL CONFLICT (For example, whether
            the person is an officer or a director of the Company and, if a
            director of the Company, whether the person is an independent
            director. The more peripheral the person's relationship to the
            Company is, the less likely that person is to influence the
            Company's day-to-day operations and therefore the less likely the
            circumstance is to be disadvantageous to the Company);

         -  THE NATURE OF THE RELATIONSHIP OR SITUATION CREATING THE POTENTIAL
            CONFLICT OF INTEREST (For example, does the issue arise because the
            person serves as an officer of the Company and a director of a
            contracting party with the Company? Is the person a director of the
            Company and an officer of a contracting party with the Company? Is
            the person a director of the Company and a director of a contracting
            party with the Company? Or is the director or officer of the Company
            related to a person that is a director or officer of the contracting
            party with the Company? The more peripheral the relationship of the
            person to either of the companies involved, the less likely that
            person is able to influence either company's day-to-day decisions
            and therefore the less likely the relationship or activity is to be
            disadvantageous to the Company);

         -  THE NATURE OF THE COMPANY WITH WHICH THE DIRECTOR OR OFFICER IS
            AFFILIATED (For example, is the company a competitor of the Company
            or a collaborator or a supplier or customer, and how significant a
            competitor, collaborator supplier or customer is the company?);

         -  THE NATURE OF ANY PROPOSED TRANSACTION, including:

                -  the size of the transaction,

                -  whether the Company has engaged in this type of transaction
                   before, either with this party or others,

                -  other connections with the other party,

                -  leverage of the other party,

                -  whether there were unusual terms associated with the
                   transaction, and

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                -  whether the terms offered are those that the Board believes
                   would be offered or could be obtained absent the
                   relationship;

                -  the level of involvement of the officer or director involving
                   questions in any proposed transaction, including whether the
                   waiver candidate will receive any compensation or other
                   benefit tied to the transaction;

                -  whether the individual usurped a corporate opportunity;

                -  whether the proposed transaction or relationship would cause
                   a director to lose his status as an independent director; and

                -  how any related disclosure would appear in, for example, The
                   Wall Street Journal or other public forum.

         After reviewing these considerations and any others it considers
appropriate, the appropriate officer or the Nominating and Governance Committee,
as the case may be, should then consider whether the relationship or activity
(i) will adversely affect the Company, (ii) was undertaken by the individual in
good faith, (iii) constitutes a breach of loyalty to the Company and its
stockholders, (iv) constitutes a violation of law, and (v) confers an improper
personal benefit on the individual. The appropriate officer or the Nominating
and Governance Committee, as the case may be, should then be in a position to
determine if a conflict of interest exists and, if so, whether to waive the
conflict if the relationship or activity is in the best interests of the Company
or not opposed to those interests.

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