<Page>

                                                                    Exhibit 10.1

                                4,500,000 SHARES

                          HITTITE MICROWAVE CORPORATION

                                  COMMON STOCK

                             UNDERWRITING AGREEMENT

                                                                   July 21, 2005
LEHMAN BROTHERS INC.
NEEDHAM & COMPANY, LLC
PIPER JAFFRAY & CO.
THOMAS WEISEL PARTNERS LLC
   As Representatives of the several
   Underwriters listed in SCHEDULE 1 hereto,
c/o Lehman Brothers Inc.
745 Seventh Avenue
New York, New York 10019

Ladies and Gentlemen:

     Hittite Microwave Corporation, a Delaware corporation (the "COMPANY"),
proposes to issue and sell 2,700,000 shares of the Company's Common Stock, par
value $0.01 per share (the "COMMON STOCK") to the several Underwriters listed in
SCHEDULE 1 hereto (the "UNDERWRITERS"), for whom you are acting as
representatives (the "REPRESENTATIVES"), and certain stockholders of the Company
named in SCHEDULE 2 hereto (each, a "SELLING STOCKHOLDER" and collectively, the
"SELLING STOCKHOLDERS") propose severally to sell an aggregate of 1,800,000
shares of Common Stock (such 4,500,000 shares of Common Stock being hereinafter
referred to as the "FIRM SHARES") to the Underwriters. In addition, the Company
proposes to grant to the Underwriters an option to purchase up to an additional
675,000 shares of Common Stock on the terms and for the purposes set forth in
Section 3 (the "OPTION SHARES"). The Firm Shares and the Option Shares, if
purchased, are hereinafter collectively called the "SHARES." This is to confirm
the agreement concerning the purchase of the Shares from the Company and the
Selling Stockholders by the Underwriters.

     SECTION 1.   REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF THE COMPANY.
The Company represents, warrants and agrees that:

          (a)     A registration statement on Form S-1, and amendments thereto,
with respect to the Shares have (i) been prepared by the Company in conformity
with the requirements of the Securities Act of 1933, as amended (the "SECURITIES
ACT"), and the rules and regulations (the "RULES AND REGULATIONS") of the United
States Securities and Exchange Commission (the "COMMISSION") thereunder, (ii)
been filed with the

                                        1
<Page>

Commission under the Securities Act and (iii) become effective under the
Securities Act. Copies of such registration statement and each of the amendments
thereto have been delivered by the Company to the Representatives. As used in
this Agreement, "EFFECTIVE TIME" means the date and the time as of which such
registration statement, or the most recent post-effective amendment thereto, if
any, was declared effective by the Commission; "EFFECTIVE DATE" means the date
of the Effective Time; "PRELIMINARY PROSPECTUS" means each prospectus included
in such registration statement, or amendments thereof, before it became
effective under the Securities Act and any prospectus filed with the Commission
by the Company with the consent of the Representatives pursuant to Rule 424(a)
of the Rules and Regulations; "REGISTRATION STATEMENT" means such registration
statement, as amended at the Effective Time, including all information contained
in the final prospectus filed with the Commission pursuant to Rule 424(b) of the
Rules and Regulations in accordance with Section 6(a) hereof and deemed to be a
part of the Registration Statement as of the Effective Time pursuant to Rule
430A of the Rules and Regulations; and "PROSPECTUS" means such final prospectus,
as first filed with the Commission pursuant to paragraph (1) or (4) of Rule
424(b) of the Rules and Regulations. If the Company has filed an abbreviated
registration statement to register additional shares of Common Stock pursuant to
Rule 462(b) under the Securities Act (the "RULE 462 REGISTRATION STATEMENT"),
then any reference herein to the term "REGISTRATION STATEMENT" shall be deemed
to include such Rule 462 Registration Statement. The Commission has not issued
any order preventing or suspending the use of any Preliminary Prospectus.

          (b)     The Registration Statement conforms, and the Prospectus and
any further amendments or supplements to the Registration Statement or the
Prospectus will, when they become effective or are filed with the Commission, as
the case may be, conform in all material respects to the requirements of the
Securities Act and the Rules and Regulations, and the Registration Statement and
any amendment thereto does not and will not, as of the applicable effective
date, contain an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein
not misleading, and the Prospectus and any amendment or supplement thereto will
not, as of the applicable filing date and each Delivery Date (as defined below),
contain an untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein, in
the light of the circumstances under which they were made, not misleading;
provided that no representation, warranty or agreement is made as to information
contained in or omitted from the Registration Statement (or any amendment
thereto) or the Prospectus (or any amendment or supplement thereto) in reliance
upon and in conformity with written information furnished to the Company through
the Representatives by or on behalf of any Underwriter specifically for
inclusion therein.

          (c)     The Company and each of its subsidiaries have been duly
incorporated and are validly existing as corporations in good standing under the
laws of their respective jurisdictions of incorporation, are duly qualified to
do business and are in good standing as foreign corporations in each
jurisdiction in which their respective

                                        2
<Page>

ownership or lease of property or the conduct of their respective businesses
requires such qualification, except where the failure to be so qualified or in
good standing would not have a material adverse effect on the business,
condition (financial or otherwise), stockholders' equity, prospects or results
of operations of the Company and its subsidiaries, taken as a whole (a "MATERIAL
ADVERSE EFFECT"), and have all power and authority necessary to own or hold
their respective properties and to conduct the businesses in which they are
engaged. None of the subsidiaries of the Company is a "significant subsidiary",
as such term is defined in Rule 405 of the Rules and Regulations.

          (d)     The Company has an authorized capitalization as set forth in
the Prospectus. All of the issued shares of capital stock of the Company have
been duly and validly authorized and issued, are fully paid and non-assessable,
were issued in compliance with federal and state securities laws, and conform to
the description thereof contained in the Prospectus. All of the Company's
options, warrants and other rights to purchase or exchange any securities for
shares of the Company's capital stock have been duly and validly authorized and
issued, were issued in compliance with federal and state securities laws, and
conform to the description thereof contained in the Prospectus. All of the
issued shares of capital stock of each subsidiary of the Company have been duly
and validly authorized and issued and are fully paid and non-assessable and
(except for directors' qualifying shares for any foreign subsidiaries) are owned
directly or indirectly by the Company, free and clear of all liens,
encumbrances, equities or claims, except for the security interest granted in
connection with the credit facility as described in the Prospectus. None of such
securities were issued in violation of preemptive or other similar rights
arising by operation of law, under the charter and bylaws of the Company or any
of its subsidiaries or under any agreement to which the Company or any of its
subsidiaries is a party or otherwise.

          (e)     The Shares to be issued and sold by the Company to the
Underwriters hereunder have been duly and validly authorized and, when issued
and delivered against payment therefor in accordance with this Agreement, will
be duly and validly issued, fully paid and non-assessable; and the Shares will
conform to the descriptions thereof contained in the Prospectus. Upon payment
for and delivery of the Shares to be sold by the Company pursuant to this
Agreement, the Underwriters will acquire good and valid title to such Shares, in
each case free and clear of all liens, encumbrances, equities, preemptive
rights, subscription rights, other rights to purchase, voting or transfer
restrictions and other similar claims.

          (f)     The Company has all requisite corporate power and authority to
execute, deliver and perform its obligations under this Agreement. This
Agreement has been duly and validly authorized, executed and delivered by the
Company.

          (g)     The execution, delivery and performance by the Company of this
Agreement and the consummation by the Company of the transactions contemplated
hereby (the "TRANSACTIONS") will not (i) conflict with or result in a breach or
violation of any of the terms or provisions of, impose any material lien, charge
or encumbrance upon

                                        3
<Page>

any property or assets of the Company and its subsidiaries, or constitute a
default under, any indenture, mortgage, deed of trust, loan agreement or other
material agreement, license or instrument to which the Company or any of its
subsidiaries is a party or by which the Company or any of its subsidiaries is
bound or to which any of the property or assets of the Company or any of its
subsidiaries is subject, (ii) result in any violation of the provisions of the
charter or bylaws of the Company or any of its subsidiaries or (iii) result in
any material violation of any statute or any order, rule or regulation of any
court or governmental agency or body having jurisdiction over the Company or any
of its subsidiaries or any of their properties or assets; and except for the
registration of the Shares under the Securities Act and such consents,
approvals, authorizations, registrations or qualifications as may be required
under the Securities Exchange Act of 1934, as amended (the "EXCHANGE ACT"),
applicable state or foreign securities laws in connection with the purchase and
distribution of the Shares by the Underwriters, the rules of the Nasdaq Stock
Market, Inc. and the rules of the National Association of Securities Dealers,
Inc. ("NASD"), no consent, approval, authorization or order of, or filing or
registration with, any such court or governmental agency or body is required for
the execution, delivery and performance by the Company of this Agreement or any
of the other documents to be entered into by the Company in connection with the
Transactions, the compliance by the Company with all of the applicable
provisions of this Agreement, and the consummation by the Company of the
Transactions, except for such consents, approvals, authorizations, orders,
filings or registrations as have been obtained or made.

          (h)     Except as described in the Prospectus, there are no contracts,
agreements or understandings between the Company and any person granting such
person the right to require the Company to file a registration statement under
the Securities Act with respect to any securities of the Company owned or to be
owned by such person or to require the Company to include such securities in the
securities registered pursuant to the Registration Statement or in any
securities registered or to be registered pursuant to any other registration
statement filed by or required to be filed by the Company under the Securities
Act. The holders of outstanding shares of the Company's capital stock are not
entitled to preemptive or other rights to subscribe for the Shares to be sold by
the Company pursuant to this Agreement nor, to the Company's knowledge, the
Shares to be sold by the Selling Stockholders pursuant to this Agreement. Except
as disclosed in the Prospectus, upon completion of the offering, no options,
warrants or other rights to purchase, agreements or other obligations to issue,
or rights to convert any obligations into or exchange any securities for, shares
of capital stock of, or ownership interests in, the Company will be outstanding
(other than securities that may be granted by the Company after July 15, 2005
pursuant to the Company's 2005 Stock Incentive Plan).

          (i)     The Company has not sold or issued any shares of Common Stock
during the six-month period preceding the date of the Prospectus, including any
sales pursuant to Rule 144A, or Regulations D or S, under the Securities Act,
other than shares issued pursuant to employee benefit plans, equity plans or
other employee compensation plans, or pursuant to outstanding options, rights or
warrants.

                                        4
<Page>

          (j)     Neither the Company nor any of its subsidiaries has sustained,
since the date of the latest audited financial statements included in the
Prospectus, any material loss or interference with its business from fire,
explosion, flood or other calamity, whether or not covered by insurance, or from
any labor dispute or court or governmental action, order or decree, otherwise
than as set forth or contemplated in the Prospectus; and, since such date, there
has not been any change in the capital stock (other than (i) shares issued
pursuant to employee benefit plans, equity plans or other employee compensation
plans, each of which plans is described in the Prospectus, (ii) the repurchase
by the Company of 5,000 shares of Common Stock that occurred on or about June
24, 2005 and (iii) repurchases of shares of Common Stock issued to or held by
employees of the Company pursuant to the terms of employee stock repurchase
agreements providing for the Company's right of first refusal thereunder) or
long-term debt of the Company or any of its subsidiaries or any material adverse
change, or any development involving a prospective material adverse change, in
or affecting the general affairs, management, consolidated financial position,
stockholders' equity, results of operations, business or prospects of the
Company and its subsidiaries, taken as a whole, otherwise than as set forth or
contemplated in the Prospectus.

          (k)     Neither the Company nor any of its subsidiaries has any
off-balance sheet arrangement (as defined in Item 303(a)(4) of Regulation S-K)
or material liability of any nature (matured or not matured, fixed or
contingent) to, or any financial interest in, any third party or unconsolidated
entity other than as set forth in the Prospectus. The financial statements
(including the related notes and supporting schedules) filed as part of the
Registration Statement or included in the Prospectus comply as to form in all
material respects with the requirements of Regulation S-X under the Securities
Act and present fairly the financial condition, results of operations and cash
flows of the entities purported to be shown thereby, at the dates and for the
periods indicated, and have been prepared in conformity with accounting
principles generally accepted in the United States applied on a consistent basis
throughout the periods involved. The pro forma financial information included in
the Registration Statement and Prospectus has been prepared in accordance with
the applicable requirements of the Securities Act, the Rules and Regulations and
the official pronouncements, if any, of the Emerging Issues Task Force, and
includes all adjustments necessary to present fairly the pro forma financial
position of the Company presented therein at the date indicated and the results
of its operations for the respective periods specified. The other financial and
accounting data, operating data and statistical information and data that is
financial in nature included in the Prospectus is presented fairly and has been
prepared on a basis consistent in all material respects with the financial
statements filed as part of the Registration Statement and included in the
Prospectus and the books and records of the Company.

          (l)     PricewaterhouseCoopers LLP, whose report on certain financial
statements of the Company is included in the Prospectus, are and have been
independent public accountants as required by the Securities Act and the Rules
and Regulations during the period covered by the financial statements on which
they reported. Except as

                                        5
<Page>

pre-approved in accordance with the requirements set forth in Section 10A of the
Exchange Act (to the extent applicable to the Company), PricewaterhouseCoopers
LLP has not engaged in any "prohibited activities" (as defined in Section 10A of
the Exchange Act) on behalf of the Company.

          (m)     The Company and each of its subsidiaries have good and
marketable title in fee simple to all real property and good and marketable
title to all personal property owned by them, in each case free and clear of all
liens, encumbrances and defects, except (i) such as are described in the
Prospectus or (ii) such as do not materially affect the value of such property
and do not materially interfere with the use made and proposed to be made of
such property by the Company and its subsidiaries; and all real property and
assets held under lease by the Company and its subsidiaries are held by them
under valid, subsisting and enforceable leases, with such exceptions as are not
material and do not interfere with the use made and proposed to be made of such
property and buildings by the Company and its subsidiaries.

          (n)     The Company and each of its subsidiaries have all material
permits, licenses, franchises, certificates of need and other approvals or
authorizations of governmental or regulatory authorities ("PERMITS") as are
necessary under applicable law to own their properties and to conduct their
businesses in the manner described in the Prospectus; each of the Company and
its subsidiaries has fulfilled and performed all of its material obligations
with respect to the Permits, and no event has occurred which allows, or after
notice or lapse of time would allow, revocation or termination thereof or result
in any other material impairment of the rights of the holder of any such
Permits.

          (o)     The Company and each of its subsidiaries carry, or are covered
by, insurance from insurers of recognized financial responsibility in such
amounts and covering such risks as is adequate for the value of their respective
properties and as is customary for companies engaged in similar businesses in
similar industries, and all policies of insurance insuring the Company and each
of its subsidiaries or their respective businesses, assets, employees, officers
and directors are in full force and effect in all material respects.

          (p)     Except as described in the Prospectus, there are no legal or
governmental proceedings pending to which the Company or any of its subsidiaries
is a party or of which any property or assets of the Company or any of its
subsidiaries is the subject; and, to the best of the Company's knowledge, no
such proceeding is threatened or contemplated by governmental authorities or
threatened by others. The statements contained in the Prospectus under the
captions "Risk Factors--If we fail to comply with export control regulations we
could be subject to substantial fines, or other sanctions" and
"Business--Litigation" constitute a fair and accurate summary in all material
respects of the subject matter thereof.

          (q)     The Company and each of its subsidiaries own or possess, or
can acquire on reasonable terms, adequate rights to use all material patents,
patent applications, inventions, trade secrets, trademarks, service marks, trade
names, domain

                                        6
<Page>

names, trademark registrations, service mark registrations, copyrights,
know-how, manufacturing processes, formulae, licenses and other rights
(collectively, the "INTELLECTUAL PROPERTY") necessary for the conduct of their
respective businesses as now conducted and as proposed to be conducted as
described in the Prospectus; and the expected expiration of any Intellectual
Property would not have a Material Adverse Effect. Neither the Company nor any
of its subsidiaries has received any notice of any claim of any such
infringement or violation that would require disclosure in the Prospectus.
Except as described in the Prospectus, no action, suit, arbitration, or legal,
administrative or other proceeding or investigation is pending, or, to the
Company's knowledge, is threatened, that involves the Intellectual Property. The
Intellectual Property of the Company and each of its subsidiaries does not
infringe or conflict with any right or valid and enforceable patent of any third
party, or any discovery, invention, product or process which is the subject of a
valid patent application filed by any third party of which the Company is aware.
The Company is not subject to any judgment, order, writ, injunction or decree of
any court or any federal, state, local, foreign or other governmental
department, commission, board, bureau, agency or instrumentality, domestic or
foreign, or any arbitrator, nor has it entered into or is a party to any
contract that restricts or impairs the use of any Intellectual Property in a
manner that would reasonably be expected to have a Material Adverse Effect. The
security measures taken and the protection afforded by the Company and each of
its subsidiaries to its trade secrets and other material non-patented technology
are substantially similar to the security measures taken and the protection
afforded by similarly situated companies in the Company's industry. Except as
disclosed in the Prospectus, to the Company's knowledge, no person is infringing
or violating the Company's rights with respect to the Intellectual Property.

          (r)     There are no contracts or other documents that are required to
be described in the Prospectus or filed as exhibits to the Registration
Statement by the Securities Act or by the Rules and Regulations that have not
been described in the Prospectus or filed as exhibits to the Registration
Statement.

          (s)     No relationship, direct or indirect, exists between or among
the Company or any subsidiary on the one hand, and the directors, officers,
stockholders, customers or suppliers of the Company on the other hand, that is
required to be described in the Prospectus that is not so described. Since the
date on which the Registration Statement was first filed with the Commission,
the Company has not, directly or indirectly, including through any subsidiary,
extended or maintained credit, or arranged for the extension of credit, or
renewed an extension of credit, in the form of a personal loan to or for any of
its directors or executive officers.

          (t)     No material labor disturbance by the employees of the Company
or any of its subsidiaries exists or, to the knowledge of the Company, is
imminent.

          (u)     The Company and each of its subsidiaries is in compliance in
all material respects with all presently applicable provisions of the Employee
Retirement Income Security Act of 1974, as amended, including the regulations
and published

                                        7
<Page>

interpretations thereunder ("ERISA"); no "REPORTABLE EVENT" (as defined in
ERISA) has occurred with respect to any "PENSION PLAN" (as defined in ERISA) for
which the Company and each of its subsidiaries would be reasonably likely to
have any liability; the Company and each of its subsidiaries has not incurred
and does not expect to incur liability under (i) Title IV of ERISA with respect
to termination of, or withdrawal from, any "PENSION PLAN" or (ii) Sections 412
or 4971 of the Internal Revenue Code of 1986, as amended, including the
regulations and published interpretations thereunder (the "CODE"); and each
"PENSION PLAN" for which the Company and each of its subsidiaries would have any
liability that is intended to be qualified under Section 401(a) of the Code is
so qualified in all material respects and nothing has occurred, whether by
action or by failure to act, which would reasonably be expected to cause the
loss of such qualification.

          (v)     The Company and each of its subsidiaries have filed all
foreign, federal, state and local income and franchise tax returns required to
be filed through the date hereof and have paid all taxes due thereon (except
such taxes as the Company or any of its subsidiaries is challenging in good
faith), except where the failure to file any such return or to pay any such tax
would not have a Material Adverse Effect, and no tax deficiency has been
determined adversely to the Company or any of its subsidiaries which has had
(nor does the Company have any knowledge of any tax deficiency which, if
determined adversely to the Company or any of its subsidiaries, would reasonably
be expected to have) a Material Adverse Effect.

          (w)     Since the date as of which information is given in the
Prospectus through the date hereof, and except as may otherwise be disclosed in
the Prospectus, the Company has not (i) issued or granted any securities other
than shares or stock options issued or granted pursuant to employee benefit
plans, equity plans or other employee compensation plans, or pursuant to
outstanding options, rights or warrants, (ii) incurred any liability or
obligation, direct or contingent, other than liabilities and obligations which
were incurred in the ordinary course of business, (iii) entered into any
material transaction not in the ordinary course of business or (iv) declared or
paid any dividend on its capital stock. The cash dividend in the aggregate
amount of approximately $34.2 million payable immediately prior to the First
Delivery Date (A) has been duly and validly authorized by all necessary
corporate action on the part of the Company and its stockholders, (B) has not
resulted and will not result in a breach or violation of the terms or provisions
of any material agreement, license or instrument to which the Company or any of
its subsidiaries is a party or by which the Company or any of its subsidiaries
is bound or to which any of the property or assets of the Company or any of its
subsidiaries is subject, (C) has not resulted and will not result in any
violation of the provisions of the charter or bylaws of the Company or any of
its subsidiaries and (D) has not resulted and will not result in any material
violation of any statute or any order, rule or regulation of any court or
governmental agency or body having jurisdiction over the Company or any of its
subsidiaries or any of their properties or assets. The Prospectus contains a
fair and accurate summary in all material respects of such cash dividend under
the heading "Dividend Policy."

                                        8
<Page>

          (x)     The Company and each of its subsidiaries (i) makes and keeps
accurate books and records and (ii) maintains a system of internal accounting
controls that provides reasonable assurance that (A) transactions are executed
in accordance with management's authorization, (B) transactions are recorded as
necessary to permit preparation of its financial statements in conformity with
accounting principles generally accepted in the United States and to maintain
accountability for its assets, (C) access to its assets is permitted only in
accordance with management's authorization, (D) the recorded accountability for
its assets is compared with existing assets at reasonable intervals and (E)
material information related to such controls is reported or otherwise made
known to the Company's Chief Executive Officer and Chief Financial Officer.

          (y)     Neither the Company nor any of its subsidiaries (i) is in
violation of its charter or bylaws (or similar organizational documents), (ii)
is in default, and no event has occurred which, with notice or lapse of time or
both, would constitute such a default, in the due performance or observance of
any term, covenant or condition contained in any indenture, mortgage, deed of
trust, loan agreement or other agreement or instrument to which it is a party or
by which it is bound or to which any of its properties or assets is subject or
(iii) is in violation of any law, ordinance, governmental rule, regulation or
court decree to which it or its property or assets is subject, except in the
case of clause (ii) or (iii) for such violations, defaults and events as would
not have a Material Adverse Effect.

          (z)     Neither the Company nor any of its subsidiaries, nor any
director, officer, employee or agent of the Company or any of its subsidiaries
or any stockholder thereof acting on behalf of the Company or any of its
subsidiaries, has used any corporate funds for any unlawful contribution, gift,
entertainment or other unlawful expense relating to political activity; made any
direct or indirect unlawful payment to any foreign or domestic government
official or employee from corporate funds; violated or is in violation of any
provision of the Foreign Corrupt Practices Act of 1977; or made any bribe,
rebate, payoff, influence payment, kickback or other unlawful payment.

          (aa)    The Company and each of its subsidiaries (i) are, and at all
prior times were, in compliance with any and all applicable foreign, federal,
state and local laws, regulations, ordinances, rules, orders, judgments,
decrees, permits or other legal requirements relating to the protection of human
health and safety, the environment, natural resources or hazardous or toxic
substances or wastes, pollutants or contaminants ("ENVIRONMENTAL LAWS"), which
compliance includes obtaining, maintaining and complying with all permits and
authorizations and approvals required by Environmental Laws to conduct their
respective businesses and (ii) have not received notice of any actual or
potential liability under Environmental Laws for the investigation or
remediation of any disposal or release of hazardous or toxic substances or
wastes, pollutants or contaminants, except in the case of clause (i) or (ii)
where such non-compliance with or liability under Environmental Laws would not,
individually or in the aggregate, reasonably be expected to have a Material
Adverse Effect; and neither the Company nor any of its subsidiaries has been
named as a "potentially responsible party" under the Comprehensive Environmental
Response, Compensation, and Liability Act of

                                        9
<Page>

1980, as amended, or any other similar Environmental Law, except with respect to
any matters, individually or in the aggregate, that would not have a Material
Adverse Effect. Except as described in the Prospectus, (i) none of the Company
and its subsidiaries is a party to any proceeding under Environmental Laws in
which a governmental authority is also a party, other than such proceedings
regarding which the Company believes no monetary penalties of $100,000 or more
will be imposed, and (ii) none of the Company and its subsidiaries anticipates
material capital expenditures relating to Environmental Laws.

          (bb)    Neither the Company nor any of its subsidiaries is, nor, as of
the applicable Delivery Date (as defined below) and after giving effect to the
Transactions and the application of the net proceeds therefrom as described in
the Prospectus, will be, an "investment company" or a company "controlled" by an
"investment company" within the meaning of the Investment Company Act of 1940,
as amended, and the rules and regulations of the Commission thereunder.

          (cc)    The Company and each of its subsidiaries have established and
maintain disclosure controls and procedures (as such term is defined in Rule
13a-15 under the Exchange Act). Such disclosure controls and procedures are
designed to ensure that information required to be disclosed by the Company in
the reports that it files or submits under the Exchange Act is recorded,
processed, summarized and reported, within the time periods specified in the
Commission's rules and forms, and include, without limitation, controls and
procedures designed to ensure that information required to be disclosed by the
Company in the reports that it files or submits under the Exchange Act is
accumulated and communicated to the Company's management, including its
principal executive and principal financial officers, or persons performing
similar functions, as appropriate to allow timely decisions regarding required
disclosure. Such disclosure controls and procedures are effective in all
material respects to perform the functions for which they were established.

          (dd)    Since the date of the most recent balance sheet of the Company
and its consolidated subsidiaries audited by PricewaterhouseCoopers LLP and
reviewed by the audit committee of the board of directors of the Company, the
Company has not been advised of and is not aware of (i) any significant
deficiency or material weaknesses in the design or operation of internal control
over financial reporting that is reasonably likely to adversely affect the
Company's ability to record, process, summarize and report financial data or any
material weaknesses in internal controls; or (ii) any fraud that involves
management or other employees who have a significant role in the Company's
internal control over financial reporting.

          (ee)    Since the date of the most recent balance sheet of the Company
and its consolidated subsidiaries reviewed or audited by PricewaterhouseCoopers
LLP, there has been no change in the Company's internal control over financial
reporting that has materially affected, or is reasonably likely to materially
affect, the Company's internal control over financial reporting.

                                       10
<Page>

          (ff)    The Company is in material compliance with all applicable
provisions of the Sarbanes-Oxley Act of 2002, including the rules and
regulations of the Commission promulgated thereunder, and as of the date hereof,
the Company is aware of no reason that its quarterly report on Form 10-Q for the
fiscal quarter ended June 30, 2005 would not be accompanied by the
certifications required to be filed or submitted by the Company's chief
executive officer and chief financial officer pursuant to the Sarbanes-Oxley Act
and the rules and regulations promulgated thereunder.

          (gg)    To the extent permitted by the terms of any option issued
under the Company's Amended and Restated 1996 Stock Option Plan or 2005 Stock
Incentive Plan (collectively, the "PLANS"), the Company (i) has exercised its
right to cause the holder of such option, or any shares of Common Stock issued
under such option, as the case may be, to be bound not to engage in any of the
transactions prohibited by the terms of the Lock-up Letter (as defined in
Section 6(j) below) for a period of 180 days after the date of the Prospectus
(the "PLAN LOCK-UP") and (ii) has imposed a stop-transfer instruction with the
Company's transfer agent with respect to the Plan Lock-up.

          (hh)    Except as disclosed in the Prospectus, the holders of at least
98% of the outstanding shares of the Company's capital stock as of the date
hereof, including securities convertible into or exercisable or exchangeable for
shares of capital stock as of the date hereof, have executed Lock-up Letters (as
described in Section 6(j)).

          (ii)    The Company has not distributed and, prior to the later to
occur of any Delivery Date and completion of the distribution of the Shares,
will not distribute, any offering material in connection with the offering and
sale of the Shares other than the Preliminary Prospectus and the Prospectus.

          (jj)    The Company has not taken and will not take, directly or
indirectly, any action designed to or which has constituted or which might
reasonably be expected to cause or result in the stabilization or manipulation
of the price of any security of the Company to facilitate the sale or resale of
the Shares.

          (kk)    The Shares have been approved for quotation, subject to notice
of issuance, on The Nasdaq National Market.

     SECTION 2.   REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF THE SELLING
STOCKHOLDERS. Each Selling Stockholder severally represents, warrants and agrees
that:

          (a)     The Selling Stockholder has, and immediately prior to the
First Delivery Date the Selling Stockholder will have, good and valid title to
the Shares to be sold by the Selling Stockholder hereunder on such date, free
and clear of all liens, encumbrances, equities or claims (except such as may
arise under this Agreement, the Custody Agreement and the Power of Attorney,
each as defined below); and upon delivery of such Shares and payment therefor
pursuant hereto, good and valid title to such Shares, free and clear of all
liens, encumbrances, equities or claims, will pass to the several Underwriters.

                                       11
<Page>

          (b)     The Selling Stockholder has placed in custody under a custody
agreement (the "CUSTODY AGREEMENT" and, together with all other similar
agreements executed by the other Selling Stockholders, the "CUSTODY AGREEMENTS")
with the Company, as custodian (the "CUSTODIAN"), for delivery under this
Agreement, certificates in negotiable form (with signature guaranteed by a
commercial bank or trust company having an office or correspondent in the United
States or a member firm of the New York or American Stock Exchanges)
representing the Shares to be sold by the Selling Stockholder hereunder.

          (c)     The Selling Stockholder has duly and irrevocably executed and
delivered a power of attorney (the "POWER OF ATTORNEY" and, together with all
other similar agreements executed by the other Selling Stockholders, the "POWERS
OF ATTORNEY") appointing Stephen G. Daly and William W. Boecke, or either of
them, as attorneys-in-fact, with full power of substitution, and with full
authority (exercisable by any one or more of them) to execute and deliver this
Agreement and to take such other action as may be necessary or desirable to
carry out the provisions hereof on behalf of the Selling Stockholder.

          (d)     The Selling Stockholder has full right, power and authority to
enter into this Agreement, the Power of Attorney and the Custody Agreement; the
execution, delivery and performance of this Agreement, the Power of Attorney and
the Custody Agreement by the Selling Stockholder, the compliance by the Selling
Stockholder with all of the applicable provisions of this Agreement, the Power
of Attorney and the Custody Agreement, and the consummation by each Selling
Stockholder of the transactions contemplated hereby and thereby will not (i)
result in a breach or violation of any of the terms or provisions of, or
constitute a default under, any indenture, mortgage, deed of trust, loan
agreement or other agreement or instrument to which the Selling Stockholder is a
party or by which the Selling Stockholder is bound or to which any of the
property or assets of the Selling Stockholder is subject, except where such
breach, violation or default would not adversely affect the Selling
Stockholder's ability to perform its obligations under this Agreement, the Power
of Attorney and the Custody Agreement, (ii) if the Selling Stockholder is not a
natural person, result in any violation of the provisions of the charter or
bylaws, articles of partnership, deed of trust or other organization documents
of the Selling Stockholder or (iii) result in any material violation of any
statute or any order, rule or regulation of any court or governmental agency or
body having jurisdiction over the Selling Stockholder or any of its properties
or assets; and, except for the registration of the Shares under the Securities
Act and such consents, approvals, authorizations, registrations or
qualifications as may be required under the Exchange Act, applicable state or
foreign securities laws in connection with the purchase and distribution of the
Shares by the Underwriters, the rules of the Nasdaq Stock Market, Inc. or the
rules of the NASD, no consent, approval, authorization or order of, or filing or
registration with, any such court or governmental agency or body is required for
the execution, delivery and performance of this Agreement, the Power of Attorney
or the Custody Agreement by the Selling Stockholder, the compliance by the
Selling Stockholder with all of the applicable provisions of this Agreement, the
Power of

                                       12
<Page>

Attorney and the Custody Agreement, and the consummation by the Selling
Stockholder of the transactions contemplated hereby and thereby, except for such
consents, approvals, authorizations, orders, filings or registrations as have
been obtained or made.

          (e)     To the extent that any statements or omissions made in the
Registration Statement, any Preliminary Prospectus, the Prospectus or any
amendment or supplement thereto are made in reliance upon and in conformity with
written information furnished to the Company by such Selling Stockholder
expressly for use therein, such Preliminary Prospectus and the Registration
Statement did not, and the Prospectus and any further amendments or supplements
to the Registration Statement and the Prospectus, when they become effective or
are filed with the Commission, as the case may be, will not, contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading.

          (f)     The Selling Stockholder is not prompted to sell the Shares by
any information concerning the Company that is not set forth in the Registration
Statement and the Prospectus.

          (g)     The Selling Stockholder has not taken and will not take,
directly or indirectly, any action designed to or which has constituted or which
might reasonably be expected to cause or result in the stabilization or
manipulation of the price of any security of the Company to facilitate the sale
or resale of the Shares.

          (h)     This Agreement has been duly authorized (if applicable),
executed and delivered by or on behalf of the Selling Stockholder.

     SECTION 3.   PURCHASE OF THE SHARES BY THE UNDERWRITERS. On the basis of
the representations and warranties contained in, and subject to the terms and
conditions of, this Agreement, the Company agrees to sell 2,700,000 shares of
the Firm Shares, and each Selling Stockholder hereby agrees to sell the number
of shares of the Firm Shares set forth opposite its name in SCHEDULE 2 hereto,
to the several Underwriters, and each of the Underwriters, severally and not
jointly, agrees to purchase the number of shares of the Firm Shares set forth
opposite that Underwriter's name in SCHEDULE 1 hereto. Each Underwriter shall be
obligated to purchase from the Company and from each Selling Stockholder that
number of Firm Shares obtained by multiplying 2,700,000 Firm Shares, in the case
of the Company, and the number of Firm Shares set forth opposite the name of
such Selling Stockholder in SCHEDULE 2 hereto, in the case of a Selling
Stockholder, in each case by a fraction the numerator of which is the number of
Firm Shares set forth opposite the name of such Underwriter in SCHEDULE 1 hereto
and the denominator of which is the total number of Firm Shares. The respective
purchase obligations of the Underwriters with respect to the Firm Shares shall
be rounded among the Underwriters to avoid fractional shares, as the
Representatives may determine.

In addition, the Company grants to the Underwriters an option to purchase up to
675,000 shares of Option Shares. Such option is granted for the purpose of
covering over-allotments in the sale of Firm Shares and is exercisable as
provided in Section 5 hereof.

                                       13
<Page>

Shares of Option Shares shall be purchased severally for the account of the
Underwriters in proportion to the number of shares of Firm Shares set forth
opposite the name of such Underwriters in SCHEDULE 1 hereto. The respective
purchase obligations of each Underwriter with respect to the Option Shares shall
be adjusted by the Representatives so that no Underwriter shall be obligated to
purchase Option Shares other than in 100 share amounts.

The price of both the Firm Shares and any Option Shares shall be $15.81 per
share.

The Company and the Selling Stockholders shall not be obligated to deliver any
of the Shares to be delivered on any Delivery Date, except upon payment for all
the Shares to be purchased on such Delivery Date as provided herein.

     SECTION 4.   OFFERING OF SHARES BY THE UNDERWRITERS. Upon authorization
by the Representatives of the release of the Firm Shares, the several
Underwriters propose to offer the Firm Shares for sale upon the terms and
conditions set forth in the Prospectus.

     SECTION 5.   DELIVERY OF AND PAYMENT FOR THE SHARES. Delivery of and
payment for the Firm Shares shall be made at the offices of Foley Hoag LLP,
World Trade Center West, 155 Seaport Boulevard, Boston, Massachusetts 02210, at
10:00 A.M., New York City time, on the fourth full business day following the
date of this Agreement or at such other date, time or place as shall be
determined by agreement between the Representatives and the Company. This date
and time are sometimes referred to as the "FIRST DELIVERY DATE." On the First
Delivery Date, the Company and the Selling Stockholders shall deliver or cause
to be delivered certificates representing the Firm Shares to the Representatives
for the account of each Underwriter against payment to or upon the order of the
Company and the Selling Stockholders of the purchase price by wire transfer in
immediately available funds. Time shall be of the essence, and delivery at the
time and place specified pursuant to this Agreement is a further condition of
the obligation of each Underwriter hereunder. Upon delivery, the Firm Shares
shall be registered in such names and in such denominations as the
Representatives shall request in writing not less than two full business days
prior to the First Delivery Date. For the purpose of expediting the checking and
packaging of the certificates for the Firm Shares, the Company and the Selling
Stockholders shall make the certificates representing the Firm Shares available
for inspection by the Representatives in Boston, Massachusetts, not later than
2:00 P.M., New York City time, on the business day prior to the First Delivery
Date.

The option granted in Section 3 will expire 30 days after the date of this
Agreement and may be exercised in whole or in part from time to time by written
notice being given to the Company by the Representatives. Such notice shall set
forth the aggregate number of shares of Option Shares as to which the option is
being exercised, the names in which the shares of Option Shares are to be
registered, the denominations in which the shares of Option Shares are to be
issued and the date and time, as determined by the Representatives, when the
shares of Option Shares are to be delivered; provided, however, that this date
and time shall not be earlier than the First Delivery Date nor earlier than the
second business day after the date on which the option shall have been

                                       14
<Page>

exercised nor later than the fifth business day after the date on which the
option shall have been exercised. The date and time the shares of Option Shares
are delivered are sometimes referred to as a "SUBSEQUENT DELIVERY DATE" and the
First Delivery Date and any Subsequent Delivery Date are sometimes each referred
to as a "DELIVERY DATE". Delivery of and payment for the Option Shares shall be
made at the place specified in the first sentence of the first paragraph of this
Section 5 (or at such other place as shall be determined by agreement between
the Representatives and the Company) at 10:00 A.M., New York City time, on each
such Subsequent Delivery Date. On each such Subsequent Delivery Date, the
Company and the Selling Stockholders shall deliver or cause to be delivered the
certificates representing the Option Shares to be purchased on such Subsequent
Delivery Date to the Representatives for the account of each Underwriter against
payment to or upon the order of the Company and the Selling Stockholders of the
purchase price by wire transfer in immediately available funds. Time shall be of
the essence, and delivery at the time and place specified pursuant to this
Agreement is a further condition of the obligation of each Underwriter
hereunder. Upon delivery, the Option Shares shall be registered in such names
and in such denominations as the Representatives shall request in the aforesaid
written notice. For the purpose of expediting the checking and packaging of the
certificates for the Option Shares, the Company and the Selling Stockholders
shall make the certificates representing the Option Shares available for
inspection by the Representatives in New York, New York, not later than 2:00
P.M., New York City time, on the business day prior to each such Subsequent
Delivery Date.

     SECTION 6.   FURTHER AGREEMENTS OF THE COMPANY.  The Company agrees:

          (a)     To prepare the Prospectus in a form approved by the
Representatives and to file such Prospectus pursuant to Rule 424(b) under the
Securities Act not later than the Commission's close of business on the second
business day following the execution and delivery of this Agreement or, if
applicable, such earlier time as may be required by Rule 430A(a)(3) under the
Securities Act; to make no further amendment or any supplement to the
Registration Statement or to the Prospectus except as provided herein; to advise
the Representatives, promptly after it receives notice thereof, of the time when
any amendment to the Registration Statement has been filed or becomes effective
or any supplement to the Prospectus or any amended Prospectus has been filed and
to furnish the Representatives with copies thereof; to advise the
Representatives, promptly after it receives notice thereof, of the issuance by
the Commission of any stop order or of any order preventing or suspending the
use of any Preliminary Prospectus or the Prospectus, of the suspension of the
qualification of the Shares for offering or sale in any jurisdiction, of the
initiation or threatening of any proceeding for any such purpose, or of any
request by the Commission for the amending or supplementing of the Registration
Statement or the Prospectus or for additional information; and, in the event of
the issuance of any stop order or of any order preventing or suspending the use
of any Preliminary Prospectus or the Prospectus or suspending any such
qualification, to use promptly its best efforts to obtain its withdrawal;

                                       15
<Page>

          (b)     To furnish promptly to each of the Representatives and to
counsel for the Underwriters a signed copy of the Registration Statement as
originally filed with the Commission, and each amendment thereto filed with the
Commission, including all consents and exhibits filed therewith;

          (c)     To deliver promptly to the Representatives such number of the
following documents as the Representatives shall reasonably request: (i)
conformed copies of the Registration Statement as originally filed with the
Commission and each amendment thereto (in each case excluding exhibits) and (ii)
each Preliminary Prospectus, the Prospectus and any amended or supplemented
Prospectus; and, if the delivery of a prospectus is required at any time after
the Effective Time in connection with the offering or sale of the Shares and if
at such time any events shall have occurred as a result of which the Prospectus
as then amended or supplemented would include an untrue statement of a material
fact or omit to state any material fact necessary in order to make the
statements therein, in the light of the circumstances under which they were made
when such Prospectus is delivered, not misleading, or, if for any other reason
it shall be necessary to amend or supplement the Prospectus in order to comply
with the Securities Act, to notify the Representatives and, upon their request,
to prepare and file such amendment or supplement to the Prospectus and to
furnish without charge to each Underwriter and to any dealer in securities as
many copies as the Representatives may from time to time reasonably request of
an amended or supplemented Prospectus which will correct such statement or
omission or effect such compliance;

          (d)     To file promptly with the Commission any amendment to the
Registration Statement or the Prospectus or any supplement to the Prospectus
that may, in the reasonable judgment of the Company or the Representatives, be
required by the Securities Act or requested by the Commission;

          (e)     Prior to filing with the Commission any amendment to the
Registration Statement or supplement to the Prospectus or any Prospectus
pursuant to Rule 424 of the Rules and Regulations, to furnish a copy thereof to
the Representatives and counsel for the Underwriters to allow the
Representatives and their counsel a reasonable period of time to review and
comment thereon prior to filing and not to file any such amendment or supplement
to which the Representatives reasonably object;

          (f)     As soon as practicable after the Effective Date, to make
generally available to the Company's security holders and to deliver to the
Representatives an earnings statement of the Company and its subsidiaries (which
need not be audited) complying with Section 11(a) of the Securities Act and the
Rules and Regulations (including, at the option of the Company, Rule 158);

          (g)     For a period of five years following the Effective Date, to
furnish to the Representatives copies of all materials furnished by the Company
to its stockholders and all public reports and all reports and financial
statements furnished by the Company to the principal national securities
exchange or automatic quotation system upon which the Common Stock may be listed
or quoted pursuant to requirements of or

                                       16
<Page>

agreements with such exchange or automatic quotation system or to the Commission
pursuant to the Exchange Act or any rule or regulation of the Commission
thereunder, other than documents filed by the Company with the Commission and
available electronically through the Commission's EDGAR system (or any successor
system);

          (h)     Promptly from time to time to take such action as the
Representatives may reasonably request to qualify the Shares for offering and
sale under the securities laws of such jurisdictions as the Representatives may
request and to comply with such laws so as to permit the continuance of sales
and dealings therein in such jurisdictions for as long as may be necessary to
complete the distribution of the Shares; provided that in connection therewith
the Company shall not be required to qualify as a foreign corporation or to file
a general consent to service of process in any jurisdiction to which it is not
otherwise subject;

          (i)     For a period of 180 days from the date of the Prospectus (the
"LOCK-UP PERIOD"), not to, directly or indirectly: (i) offer for sale, sell,
pledge or otherwise dispose of (or enter into any transaction or device which is
designed to, or could be expected to, result in the disposition by any person at
any time in the future of) any shares of Common Stock or securities convertible
into or exchangeable for Common Stock (other than the Shares and shares issued
or issuable pursuant to any of the Plans or pursuant to currently outstanding
options, warrants or rights), or sell or grant options, rights or warrants with
respect to any shares of Common Stock or securities convertible into or
exchangeable for Common Stock (other than pursuant to any of the Plans); (ii)
enter into any swap or other derivatives transaction that transfers to another,
in whole or in part, any of the economic benefits or risks of ownership of such
shares of Common Stock (other than the Shares and shares issued or issuable
pursuant to any of the Plans or pursuant to currently outstanding options,
warrants or rights), whether any such transaction described in clause (i) or
(ii) above is to be settled by delivery of Common Stock or other securities, in
cash or otherwise; (iii) file or cause to be filed a registration statement with
respect to any shares of Common Stock or securities convertible, exercisable or
exchangeable into Common Stock or any other securities of the Company (other
than any registration statement or statements on Form S-8 relating to the
Plans); or (iv) publicly disclose the intention to do any of the acts prohibited
by the foregoing, in each case without the prior written consent of Lehman
Brothers Inc. on behalf of the Underwriters; PROVIDED, HOWEVER, that, if (1)
during the last 17 days of the Lock-Up Period, the Company issues an earnings
release or discloses, through a press release or the filing of a Current Report
on Form 8-K, the occurrence of a material event relating to the Company, or
Lehman Brothers, Inc., on behalf of the Underwriters, shall notify the Company
in writing that, in its reasonable judgment, a material event relating to the
Company has occurred, or (2) prior to the expiration of the Lock-Up Period, the
Company announces that it will issue an earnings release during the 16-day
period beginning on the last day of the Lock-Up Period, then the restrictions
described in this Section 6(i) shall continue to apply until the expiration of
the 18-day period beginning on the issuance of the earnings release or the
announcement of the material news or the occurrence of the material event,
unless Lehman Brothers Inc., on behalf of the

                                       17
<Page>

Underwriters, waives, in writing, such extension; PROVIDED FURTHER, HOWEVER,
that the restrictions described in this Section 6(i) shall automatically
terminate in the event that the Company issues any shares of Common Stock or
securities convertible into or exchangeable for Common Stock in an equity or
debt offering led or managed by any of the Representatives;

          (j)     To use its commercially reasonable efforts to cause each
stockholder, officer and director of the Company to furnish to the
Representatives, prior to the First Delivery Date, a letter or letters,
substantially in the form previously provided to counsel for the Company (the
"LOCK-UP LETTER"), pursuant to which each such person shall agree, subject to
certain exceptions in the Lock-up Letter, not to, directly or indirectly, (i)
offer for sale, sell, pledge or otherwise dispose of (or enter into any
transaction or device which is designed to, or could be expected to, result in
the disposition by any person at any time in the future of) any shares of Common
Stock or securities convertible into or exchangeable for Common Stock or (ii)
enter into any swap or other derivatives transaction that transfers to another,
in whole or in part, any of the economic benefits or risks of ownership of such
shares of Common Stock, whether any such transaction described in clause (i) or
(ii) above is to be settled by delivery of Common Stock or other securities, in
cash or otherwise, in each case for a period of 180 days from the date of the
Prospectus, without the prior written consent of Lehman Brothers Inc. on behalf
of the Underwriters;

          (k)     To apply to have the Shares listed for quotation on The Nasdaq
National Market, and to use its best efforts to complete that application,
subject only to official notice of issuance, prior to the First Delivery Date;

          (l)     To apply the net proceeds from the sale of the Shares being
sold by the Company as set forth in the Prospectus;

          (m)     To take such steps within its power as shall be necessary to
ensure that neither the Company nor any subsidiary shall become an "investment
company" or a company "controlled" by an "investment company" within the meaning
of the Investment Company Act of 1940, as amended.

          (n)     To enforce the terms of the Plan Lock-up with each of its
directors, officers and stockholders and each person who acquires shares of
Common Stock before the expiration of such Plan Lock-up pursuant to the exercise
of any option or right granted under the Plans, except as otherwise permitted
with the prior written consent of Lehman Brothers Inc. on behalf of the
Underwriters; and, unless otherwise instructed by Lehman Brothers Inc., to issue
and impose a stop-transfer instruction with the Company's transfer agent with
respect to the Plan Lock-up.

          The Company further acknowledges and agrees that the Underwriters'
research analysts and research departments are required to be independent from
their respective investment banking divisions and are subject to certain
regulations and internal policies, and that such Underwriters' research analysts
may hold and make statements or

                                       18
<Page>

investment recommendations and/or publish research reports with respect to the
Company and/or the offering of the Shares that differ from the views of the
Underwriters' respective investment bankers. The Company acknowledges that each
of the Underwriters is a full-service securities firm and, as such, from time to
time, subject to applicable securities laws, may effect transactions for its own
account or the account of its customers and hold long or short positions in debt
or equity securities of the Company.

     SECTION 7.   FURTHER AGREEMENTS OF THE SELLING STOCKHOLDERS. Each
Selling Stockholder agrees:

          (a)     To comply with the terms and conditions of the Lock-up Letter
between such Selling Stockholder and the Representatives;

          (b)     That the Shares to be sold by the Selling Stockholder
hereunder which are represented by the certificates held in custody for the
Selling Stockholder are subject to the interest of the Underwriters and the
other Selling Stockholders hereunder, that the arrangements made by the Selling
Stockholder for such custody are to that extent irrevocable, and that the
obligations of the Selling Stockholder hereunder shall not be terminated by any
act of the Selling Stockholder, by operation of law, by the death or incapacity
of any individual Selling Stockholder or, in the case of a trust, by the death
or incapacity of any executor or trustee or the termination of such trust, or
the occurrence of any other event; and

          (c)     To deliver to the Representatives prior to the First Delivery
Date, a properly completed and executed United States Treasury Department Form
W-8 (if the Selling Stockholder is a non-United States person) or Form W-9 (if
the Selling Stockholder is a United States person).

     SECTION 8.   EXPENSES. Except as otherwise agreed to in writing by the
Company and Lehman Brothers Inc. on behalf of the Representatives, the Company
agrees to pay all costs and expenses incident to the performance of the
obligations of the Company under this Agreement and in connection with the
Transactions, including: (a) the costs incident to the authorization, issuance,
sale and delivery of the Shares being sold by it hereunder and any taxes payable
in that connection; (b) the costs incident to the preparation, printing and
filing under the Securities Act of the Registration Statement and any amendments
and exhibits thereto; (c) the costs of distributing the Registration Statement
as originally filed and each amendment thereto and any post-effective amendments
thereof (including, in each case, exhibits), any Preliminary Prospectus, the
Prospectus and any amendment or supplement to the Prospectus, all as provided in
this Agreement; (d) the costs of producing and distributing this Agreement, the
Agreement Between U.S. Underwriters and International Managers, any Supplemental
Agreement Among U.S. Underwriters and any other related documents in connection
with the offering, purchase, sale and delivery of the Shares; (e) the fees and
expenses of the Custodian and any attorney-in-fact and the costs of delivering
and distributing the Custody Agreements and the Powers of Attorney; (f) the
filing fees incident to securing the review by the NASD of the terms of sale of
the Shares (including related fees and

                                       19
<Page>

expenses of counsel to the Underwriters incurred in connection with such review,
not in excess, in the aggregate, of $10,000); (g) any applicable listing,
quotation or other fees; (h) the fees and expenses (not in excess, in the
aggregate, of $10,000) of qualifying the Shares under the securities laws of the
several jurisdictions as provided in Section 6(h) and of preparing, printing and
distributing a Blue Sky Memorandum (including related fees and expenses of
counsel to the Underwriters); (i) the costs and expenses of the Company relating
to investor presentations on any "road show" undertaken in connection with the
marketing of the offering of the Shares, including, without limitation, expenses
associated with the production of road show slides and graphics, fees and
expenses of any consultants engaged in connection with the road show
presentations with the prior approval of the Company, travel and lodging
expenses of the representatives and officers of the Company and any such
consultants, and the cost of any aircraft chartered in connection with the road
show; and (j) all other costs and expenses incident to the performance of the
obligations of the Company under this Agreement; PROVIDED, HOWEVER, that, except
as provided in this Section 8 and in Section 13, the Underwriters shall pay
their own costs and expenses, including the costs and expenses of their counsel,
any transfer taxes on the Shares that they may sell and the expenses of
advertising any offering of the Shares made by the Underwriters. Except as
otherwise agreed to by the Company and the Selling Stockholders, the fees and
expenses of the Selling Stockholders shall be paid in the manner set forth in
that certain Registration Rights Agreement made as of November 20, 2000 by and
among the Company and certain of its stockholders.

     SECTION 9.   CONDITIONS OF UNDERWRITERS' OBLIGATIONS. The respective
obligations of the Underwriters hereunder are subject to the accuracy, when made
and on each Delivery Date, of the representations and warranties of the Company
and the Selling Stockholders contained herein, to the performance by the Company
and the Selling Stockholders of their respective obligations hereunder, and to
each of the following additional terms and conditions:

          (a)     The Prospectus shall have been timely filed with the
Commission in accordance with Section 6(a); no stop order suspending the
effectiveness of the Registration Statement or any part thereof shall have been
issued and no proceeding for that purpose shall have been initiated or
threatened by the Commission; and any request of the Commission for inclusion of
additional information in the Registration Statement or the Prospectus or
otherwise shall have been complied with.

          (b)     No Underwriter shall have discovered and disclosed to the
Company on or prior to such Delivery Date that the Registration Statement or the
Prospectus or any amendment or supplement thereto contains an untrue statement
of a fact that, in the opinion of such Underwriter or Wilson Sonsini Goodrich &
Rosati, Professional Corporation, counsel for the Underwriters, is material or
omits to state a fact that, in the opinion of such Underwriter or such counsel,
is material or is required to be stated therein or is necessary to make the
statements therein not misleading.

          (c)     All corporate proceedings and other legal matters incident to
the authorization, form and validity of this Agreement, the Custody Agreements,
the Powers

                                       20
<Page>

of Attorney, the Shares, the Registration Statement and the Prospectus, and all
other legal matters relating to this Agreement and the Transactions shall be
reasonably satisfactory in all material respects to counsel for the
Underwriters, and the Company and the Selling Stockholders shall have furnished
to such counsel all documents and information that they may reasonably request
to enable them to pass upon such matters.

          (d)     Foley Hoag LLP shall have furnished to the Representatives its
written opinion, as counsel to the Company, addressed to the Underwriters and
dated such Delivery Date, in form and substance satisfactory to the
Representatives, to the effect that:

                  (i)    The Company has been duly incorporated and is validly
          existing as a corporation in good standing under the laws of Delaware,
          is duly registered to do business as a foreign corporation in the
          Commonwealth of Massachusetts and has all corporate power and
          authority necessary to own or hold its properties and conduct its
          businesses as described in the Prospectus;

                  (ii)   The Company has an authorized capitalization as set
          forth in the Prospectus under the caption "Description of Capital
          Stock - General Matters," and all of the issued and outstanding shares
          of capital stock of the Company (excluding the Shares being delivered
          by the Company on such Delivery Date to the Underwriters hereunder)
          have been duly and validly authorized and issued, are fully paid and
          non-assessable and conform to the description thereof contained in the
          Prospectus;

                  (iii)  The Shares being delivered by the Company on such
          Delivery Date to the Underwriters hereunder have been duly and validly
          authorized and, when issued and delivered against payment therefor in
          accordance with the terms hereof, will be duly and validly issued,
          fully paid and non-assessable;

                  (iv)   Except as described in the Prospectus and except for
          such rights as have been waived, there are no preemptive or other
          rights to subscribe for or to purchase, nor any restriction upon the
          voting or transfer of, any of the Shares pursuant to the Company's
          certificate of incorporation or bylaws or any agreement or other
          instrument known to such counsel and to which the Company is a party;

                  (v)    To such counsel's knowledge and except for the matters
          described in the Prospectus, there are no legal or governmental
          proceedings pending or threatened to which the Company is a party or
          of which any property or assets of the Company is the subject which,
          if determined adversely to the Company, would be reasonably likely to
          have a Material Adverse Effect;

                                       21
<Page>

                  (vi)   The Registration Statement and any Rule 462(b)
          Registration Statement were declared effective under the Securities
          Act as of the date or dates specified in such opinion, the Prospectus
          was filed with the Commission pursuant to the subparagraph of Rule
          424(b) of the Rules and Regulations specified in such opinion on the
          date specified therein, and, to such counsel's knowledge, no stop
          order suspending the effectiveness of the Registration Statement has
          been issued and no proceeding for that purpose is pending or
          threatened by the Commission;

                  (vii)  The Registration Statement, as of its effective date,
          and the Prospectus, as of its filing date, and any amendments or
          supplements thereto made by the Company prior to such Delivery Date,
          as of their respective effective or filing dates (except in each case
          for the financial statements, the notes thereto, the financial
          schedules and the financial, accounting and statistical data and
          information derived therefrom, as to which such counsel need express
          no opinion) complied as to form in all material respects with the
          requirements of the Securities Act and the Rules and Regulations;

                  (viii) The statements contained in the Prospectus under the
          captions "Risk Factors - If we fail to comply with government
          contracting regulations, we could suffer a loss of revenue or incur
          price adjustments or other penalties", "Risk Factors - If we fail to
          comply with environmental regulations we could be subject to
          substantial fines or be required to suspend production, alter
          manufacturing processes or cease operations," the first three
          sentences of the third paragraph of Management's Discussion and
          Analysis of Financial Condition and Results of Operations - Recent
          Accounting Pronouncements", "Business - Government Regulation - Export
          regulations", "Business - Government Regulation - Government
          contracting regulations", "Management - Liability Limitations and
          Indemnification", "Description of Capital Stock" and the statements
          contained in Item 14 of the Registration Statement, insofar as they
          describe federal or state statutes, rules and regulations, constitute
          a fair summary thereof in all material respects, and the opinion of
          such counsel filed as Exhibit 5.1 to the Registration Statement is
          confirmed, and the Underwriters may rely upon such opinion as if it
          were addressed to them;

                  (ix)   To such counsel's knowledge, there are no contracts or
          other documents which are required to be described in the Prospectus
          or filed as exhibits to the Registration Statement by the Securities
          Act or by the Rules and Regulations that have not been so described or
          filed;

                  (x)    This Agreement has been duly authorized, executed and
          delivered by the Company;

                                       22
<Page>

                  (xi)   The issuance and sale of the Shares being delivered on
          such Delivery Date by the Company pursuant to this Agreement, the
          execution, delivery and performance by the Company of its obligations
          under this Agreement and the consummation by the Company of the
          transactions contemplated hereby will not result in a breach or
          violation of any of the terms or provisions of, or constitute a
          default under, any indenture, mortgage, deed of trust, loan agreement
          or other agreement or instrument filed as an exhibit to the
          Registration Statement, nor will such actions result in any violation
          of the provisions of the charter or bylaws of the Company or any
          material violation of any statute, order, rule or regulation known to
          such counsel of any federal or Massachusetts court or governmental
          agency or body having jurisdiction over the Company or any of its
          properties or assets; and, except for the registration of the Shares
          under the Securities Act and such consents, approvals, authorizations,
          orders, filings, registrations or qualifications as may be required
          under the Exchange Act, applicable state or foreign securities laws in
          connection with the purchase and distribution of the Shares by the
          Underwriters, the rules of the Nasdaq Stock Market, Inc. and the rules
          of the NASD, no consent, approval, authorization or order of, or
          filing or registration with, any such federal or Massachusetts court
          or governmental agency or body is required for the execution, delivery
          and performance by the Company of its obligations under this Agreement
          and the consummation by the Company of the transactions contemplated
          hereby, except for such consents, approvals, authorizations, orders,
          filings, registrations or qualifications as have been obtained or
          made;

                  (xii)  Except for the statements contained in the Prospectus
          under the heading "Description of Capital Stock--Registration Rights,"
          to such counsel's knowledge, there are no contracts or agreements
          between the Company and any person granting such person the right to
          require the Company to file a registration statement under the
          Securities Act with respect to any securities of the Company owned or
          to be owned by such person or to require the Company to include such
          securities in the securities registered pursuant to the Registration
          Statement or in any securities being registered pursuant to any other
          registration statement filed by the Company under the Securities Act;

                  (xiii) The Company is not, and after giving effect to the
          Transactions and the application of the net proceeds from the Shares
          being sold by the Company as described in the Prospectus, will not be,
          an "investment company" as defined in the Investment Company Act of
          1940, as amended.

                  (xiv)  The cash dividend in the aggregate amount of
          approximately $34.2 million payable immediately prior to the First
          Delivery Date (as defined below) (A) has been duly and validly
          authorized

                                       23
<Page>

          by all necessary corporate action on the part of the Company and its
          stockholders, (B) has not resulted and will not result in a breach or
          violation of any of the terms or provisions of any agreement, license
          or instrument to which the Company is a party or by which the Company
          is bound or to which any of the property or assets of the Company is
          subject and that is filed as an exhibit to the Registration Statement,
          except for such breaches and violations as have been validly waived,
          (C) has not resulted and will not result in any violation of the
          provisions of the charter or bylaws of the Company, (D) to such
          counsel's knowledge has not resulted and will not result in any
          violation of any statute or any order, rule or regulation of any court
          or governmental agency or body having jurisdiction over the Company or
          any of its properties or assets. The Prospectus contains a fair and
          accurate summary in all material respects of such cash dividend under
          the heading "Dividend Policy."

In rendering such opinion, such counsel may state that its opinion is limited to
matters governed by the Federal laws of the United States of America, the laws
of the Commonwealth of Massachusetts and the General Corporation Law of the
State of Delaware, that it is subject to such assumptions, limitations and
qualifications as are stated therein, and that, insofar as such opinion involves
factual matters, it has relied upon certificates of officers of the Company and
such other persons as it shall deem appropriate. Such opinion shall also be to
the effect that (i) such counsel has acted as counsel to the Company in
connection with the preparation of the Registration Statement and (ii) based on
the foregoing and such matters as such counsel shall describe therein, no facts
have come to the attention of such counsel that lead it to believe that the
Registration Statement (except in each case for the financial statements, the
notes thereto, the financial schedules and the financial, accounting and
statistical data and information derived therefrom, as to which such counsel
need express no opinion) as of the Effective Date, contained any untrue
statement of a material fact or omitted to state a material fact required to be
stated therein or necessary to make the statements therein not misleading, or
that the Prospectus (except as stated above) contains any untrue statement of a
material fact or omits to state a material fact necessary in order to make the
statements therein, in the light of the circumstances under which they were
made, not misleading. The foregoing opinion and statement may be qualified by a
statement to the effect that (other than as set forth in clause (viii and xiv)
above) such counsel does not assume any responsibility for the accuracy,
completeness or fairness of the statements contained in the Registration
Statement or the Prospectus.

          (e)     The Representatives shall have received from Iandiorio &
Teska, intellectual property counsel for the Company, such opinion, dated such
Delivery Date, with respect to the matters set forth in EXHIBIT A hereto.

          (f)     The Representatives shall have received from Wilson Sonsini
Goodrich & Rosati, Professional Corporation, counsel for the Underwriters, such
opinion, dated such Delivery Date, with respect to the issuance and sale of the
Shares, the Registration Statement, the Prospectus and other related matters as
the Representatives

                                       24
<Page>

may reasonably require, and the Company shall have furnished to such counsel
such documents as they reasonably request for the purpose of enabling them to
pass upon such matters.

          (g)     Counsel to each of the Selling Stockholders shall have
furnished to the Representatives its written opinion, as counsel to such Selling
Stockholder, addressed to the Underwriters and dated such Delivery Date, in the
form attached hereto as EXHIBIT B.

          (h)     At the time of execution of this Agreement, the
Representatives shall have received from PricewaterhouseCoopers LLP a letter, in
form and substance satisfactory to the Representatives, addressed to the
Underwriters and dated the date hereof (i) confirming that they are independent
public accountants within the meaning of the Securities Act and the Rules and
Regulations and the rules and regulations of the Public Company Accounting
Oversight Board (United States) and are in compliance with the applicable
requirements relating to the qualification of accountants under Rule 2-01 of
Regulation S-X of the Rules and Regulations and (ii) stating, as of the date
hereof (or, with respect to matters involving changes or developments since the
respective dates as of which specified financial information is given in the
Prospectus, as of a date not more than five days prior to the date hereof), the
conclusions and findings of such firm with respect to the financial information
and other matters ordinarily covered by accountants' "comfort letters" to
underwriters in connection with registered public offerings.

          (i)     With respect to the letter of PricewaterhouseCoopers LLP
referred to in the preceding paragraph and delivered to the Representatives
concurrently with the execution of this Agreement (the "INITIAL LETTER"),
PricewaterhouseCoopers LLP shall have delivered to the Representatives a letter
(the "BRING-DOWN LETTER") of such accountants, addressed to the Underwriters and
dated such Delivery Date (i) confirming that they are independent public
accountants within the meaning of the Securities Act and the Rules and
Regulations and the rules and regulations of the Public Company Accounting
Oversight Board (United States) and are in compliance with the applicable
requirements relating to the qualification of accountants under Rule 2-01 of
Regulation S-X of the Rules and Regulations, (ii) stating, as of the date of the
Bring-down Letter (or, with respect to matters involving changes or developments
since the respective dates as of which specified financial information is given
in the Prospectus, as of a date not more than five days prior to the date of the
Bring-down Letter), the conclusions and findings of such firm with respect to
the financial information and other matters covered by the Initial Letter and
(iii) confirming in all material respects the conclusions and findings set forth
in the Initial Letter.

          (j)     The Company shall have furnished to the Representatives a
certificate, dated such Delivery Date, executed on behalf of the Company by its
Chairman of the Board, its President or a Vice President and its Chief Financial
Officer stating severally that:

                                       25
<Page>

                  (i)    The representations, warranties and agreements of the
          Company in Section 1 are true and correct as of such Delivery Date;
          the Company has complied with all its agreements contained herein; and
          the conditions set forth in Sections 9(a) and 9(l) have been
          fulfilled;

                  (ii)   The signatory has carefully examined the Registration
          Statement and the Prospectus and, in his opinion (A) the Registration
          Statement and any amendment thereto did not, as of the applicable
          effective date, contain an untrue statement of a material fact or omit
          to state a material fact required to be stated therein or necessary to
          make the statements therein not misleading, and the Prospectus and any
          amendment or supplement thereto did not, as of the applicable filing
          date, and does not, as of the Delivery Date, contain an untrue
          statement of a material fact or omit to state a material fact required
          to be stated therein or necessary to make the statements therein, in
          the light of the circumstances under which they were made, not
          misleading, and (B) since the Effective Date, no event has occurred
          that should have been set forth in a supplement or amendment to the
          Registration Statement or the Prospectus that has not been so set
          forth; and

                  (iii)  To the knowledge of the signatory, the issuance and
          sale of the Shares by the Company hereunder has not been enjoined
          (temporarily or permanently) by any court or governmental body or
          agency.

          (k)     Each Selling Stockholder (or one or more attorneys in fact on
behalf of the Selling Stockholders) shall have furnished to the Representatives
on such Delivery Date a certificate, dated such Delivery Date, signed by, or on
behalf of, the Selling Stockholder (or one or more attorneys in fact) stating
that the representations, warranties and agreements of the Selling Stockholder
contained herein are true and correct as of such Delivery Date and that the
Selling Stockholder has complied with all agreements contained herein to be
performed by the Selling Stockholder at or prior to such Delivery Date.

          (l)     Neither the Company nor any of its subsidiaries shall have
sustained since the date of the latest audited financial statements included in
the Prospectus (i) any loss or interference with its business from fire,
explosion, flood or other calamity, whether or not covered by insurance, or from
any labor dispute or court or governmental action, order or decree, otherwise
than as set forth or contemplated in the Prospectus or (ii) since such date,
there shall not have been any change in the capital stock or long-term debt of
the Company or any of its subsidiaries or any change, or any development
involving a prospective change, in or affecting the general affairs, management,
financial position, stockholders' equity or results of operations of the Company
and its subsidiaries, otherwise than as set forth or contemplated in the
Prospectus, the effect of which, in any such case described in clause (i) or
(ii), is, in the judgment of the Representatives, so material and adverse as to
make it impracticable or inadvisable to proceed with the public offering or the
delivery of the Shares being

                                       26
<Page>

delivered on such Delivery Date on the terms and in the manner contemplated
herein and in the Prospectus.

          (m)     Subsequent to the execution and delivery of this Agreement
there shall not have occurred any of the following: (i) trading in securities
generally on the New York Stock Exchange or the American Stock Exchange or in
the over-the-counter market, or trading in any securities of the Company on any
exchange or in the over-the-counter market, shall have been suspended or the
settlement of such trading generally shall have been materially disrupted or
minimum prices shall have been established on any such exchange or such market
by the Commission, by such exchange or by any other regulatory body or
governmental authority having jurisdiction, (ii) a banking moratorium shall have
been declared by Federal or state authorities, (iii) the United States shall
have become engaged in hostilities, there shall have been an escalation in
hostilities involving the United States or there shall have been a declaration
of a national emergency or war by the United States or (iv) there shall have
occurred such a material adverse change in general economic, political or
financial conditions (or the effect of international conditions on the financial
markets in the United States shall be such) or there shall have occurred any
other calamity or crisis, including without limitation as a result of terrorist
activities after the date hereof, as to make it, in the judgment of the
Representatives, impracticable or inadvisable to proceed with the offering or
delivery of the Shares being delivered on such Delivery Date on the terms and in
the manner contemplated in the Prospectus.

          (n)     The Nasdaq Stock Market, Inc. shall have approved the Shares
for listing on the Nasdaq National Market, subject only to official notice of
issuance.

All opinions, letters, evidence and certificates mentioned above or elsewhere in
this Agreement shall be deemed to be in compliance with the provisions hereof
only if they are in form and substance reasonably satisfactory to counsel for
the Underwriters.

     SECTION 10.  INDEMNIFICATION AND CONTRIBUTION.

          (a)     The Company shall indemnify and hold harmless each
Underwriter, its directors, officers, employees and agents and each person, if
any, who controls any Underwriter within the meaning of Section 15 of the
Securities Act, from and against any loss, claim, damage or liability, joint or
several, or any action in respect thereof, to which that Underwriter, director,
officer, employee, agent or controlling person may become subject, under the
Securities Act or otherwise, insofar as such loss, claim, damage, liability or
action arises out of, or is based upon, (i) any untrue statement or alleged
untrue statement of a material fact contained (A) in any Preliminary Prospectus,
the Registration Statement or the Prospectus or in any amendment or supplement
thereto, or (B) in any materials or information provided to investors by, or
with the written approval of, the Company in connection with the marketing of
the offering of the Shares, including any road show or investor presentations
made to investors by the Company (whether in person or electronically)
("MARKETING MATERIALS"), (ii) the omission or alleged omission to state in any
Preliminary Prospectus,

                                       27
<Page>

the Registration Statement or the Prospectus, or in any amendment or supplement
thereto, or in any Marketing Materials, any material fact required to be stated
therein or necessary to make the statements therein not misleading, or (iii) any
act or failure to act or any alleged act or failure to act by any Underwriter in
connection with, or relating in any manner to, the Shares or the offering
contemplated hereby, and that is included as part of or referred to in any loss,
claim, damage, liability or action arising out of or based upon matters covered
by clause (i) or (ii) above (PROVIDED, HOWEVER, that the Company shall not be
liable under this clause (iii) to the extent that it is determined in a final
judgment by a court of competent jurisdiction that such loss, claim, damage,
liability or action resulted directly from any such acts or failures to act
undertaken or omitted to be taken by any Underwriter through its gross
negligence or willful misconduct), and shall reimburse each Underwriter and each
such director, officer, employee, agent or controlling person promptly upon
demand for any legal or other expenses reasonably incurred by that Underwriter,
director, officer, employee, agent or controlling person in connection with
investigating or defending or preparing to defend against any such loss, claim,
damage, liability or action as such expenses are incurred; PROVIDED, HOWEVER,
that the Company shall not be liable in any such case to the extent that any
such loss, claim, damage, liability or action arises out of, or is based upon,
any untrue statement or alleged untrue statement or omission or alleged omission
made in any Preliminary Prospectus, the Registration Statement or the
Prospectus, or in any such amendment or supplement, in reliance upon and in
conformity with written information concerning such Underwriter furnished to the
Company through the Representatives by or on behalf of any Underwriter
specifically for inclusion therein, which information consists solely of the
information specified in Section 10(f); AND PROVIDED, FURTHER, that the Company
shall not be liable in any such case to the extent that any such loss, claim,
damage, liability or action arises out of, or is based upon, any untrue
statement or alleged untrue statement or omission or alleged omission made in
any Preliminary Prospectus or any Marketing Materials if (x) the Company shall
have furnished copies of the Prospectus to the several Underwriters in the
requisite quantity and sufficiently in advance of confirmation of sale to permit
proper delivery of the Prospectus to such person at or prior to the confirmation
of sale, and the person alleging such loss, claim, damage, liability or action
purchased Shares from the Underwriters but was not sent or did not receive a
copy of the Prospectus (as then amended or supplemented); (y) such misstatement
or omission or alleged misstatement or omission was cured in the Prospectus; and
(z) the timely delivery of the Prospectus to such person would have constituted
a complete defense to the losses, claims, damages, liabilities and judgments
asserted by such person. The foregoing indemnity agreement is in addition to any
liability that the Company may otherwise have to any Underwriter or to any
director, officer, employee, agent or controlling person of that Underwriter.

          (b)     Each Selling Stockholder, severally and not jointly, shall
indemnify and hold harmless each Underwriter, its directors, officers, employees
and agents, and each person, if any, who controls any Underwriter within the
meaning of Section 15 of the Securities Act, from and against any loss, claim,
damage or liability, joint or several, or any action in respect thereof
(including, but not limited to, any loss, claim, damage, liability or

                                       28
<Page>

action relating to purchases and sales of Shares), to which that Underwriter,
director, officer, employee, agent or controlling person may become subject,
under the Securities Act or otherwise, insofar as such loss, claim, damage,
liability or action arises out of, or is based upon, (i) any untrue statement or
alleged untrue statement of a material fact contained in any Preliminary
Prospectus, the Registration Statement or the Prospectus or in any amendment or
supplement thereto, or (ii) the omission or alleged omission to state in any
Preliminary Prospectus, Registration Statement or the Prospectus, or in any
amendment or supplement thereto, any material fact required to be stated therein
or necessary to make the statements therein not misleading, but in each case
only to the extent that the untrue statement or alleged untrue statement or
omission or alleged omission was made in reliance upon and in conformity with
written information concerning such Selling Stockholder furnished to the Company
by such Selling Stockholder specifically for inclusion therein, and shall
reimburse each Underwriter, its directors, officers, employees and agents and
each such controlling person for any legal or other expenses reasonably incurred
by that Underwriter, its directors, officers, employees, agents or controlling
person in connection with investigating or defending or preparing to defend
against any such loss, claim, damage, liability or action as such expenses are
incurred; PROVIDED, HOWEVER, that the aggregate liability of any Selling
Stockholder to the Underwriters and their directors, officers, employees, agents
and controlling persons shall not exceed the aggregate purchase price, less
underwriting discounts and commissions, received by such Selling Stockholder
from the sale of Shares by it under this Agreement; PROVIDED, FURTHER, that such
Selling Stockholder shall not be liable to any Underwriter or any of its
directors, officers, employees, agents or controlling persons in any such case
to the extent that any such loss, claim, damage, liability or action arises out
of, or is based upon, any untrue statement or alleged untrue statement or
omission or alleged omission made in any Preliminary Prospectus or any Marketing
Materials if (x) the Company shall have furnished copies of the Prospectus to
the several Underwriters in the requisite quantity and sufficiently in advance
of confirmation of sale to permit proper delivery of the Prospectus to such
person at or prior to the confirmation of sale, and the person alleging such
loss, claim, damage, liability or action purchased Shares from the Underwriters
but was not sent or did not receive a copy of the Prospectus (as then amended or
supplemented); (y) such misstatement or omission or alleged misstatement or
omission was cured in the Prospectus; and (z) the timely delivery of the
Prospectus to such person would have constituted a complete defense to the
losses, claims, damages, liabilities and judgments asserted by such person; AND
PROVIDED, FURTHER, that such Selling Stockholder shall not be liable to any
Underwriter or any of its directors, officers, employees, agents or controlling
persons in any such case to the extent that any such loss, claim, damage,
liability or action arises out of, or is based upon, any untrue statement or
alleged untrue statement or omission or alleged omission made in any Preliminary
Prospectus, the Registration Statement or the Prospectus or in any such
amendment or supplement, in reliance upon and in conformity with written
information concerning such Underwriter furnished to the Company through the
Representatives by or on behalf of any Underwriter specifically for inclusion
therein, which information consists solely of the information specified in
Section 10(f). The foregoing indemnity agreement is in addition to any liability
that the Selling Stockholders

                                       29
<Page>

may otherwise have to any Underwriter or any director, officer, employee, agent
or controlling person of that Underwriter.

          (c)     Each Underwriter, severally and not jointly, shall indemnify
and hold harmless the Company, its officers who have signed the Registration
Statement, each of its directors, each Selling Stockholder, and each person, if
any, who controls the Company or any Selling Stockholder within the meaning of
Section 15 of the Securities Act, from and against any loss, claim, damage or
liability, joint or several, or any action in respect thereof, to which the
Company or any such director, officer, Selling Stockholder or controlling person
may become subject, under the Securities Act or otherwise, insofar as such loss,
claim, damage, liability or action arises out of, or is based upon, (i) any
untrue statement or alleged untrue statement of a material fact contained in any
Preliminary Prospectus, the Registration Statement or the Prospectus or in any
amendment or supplement thereto, or (ii) the omission or alleged omission to
state in any Preliminary Prospectus, the Registration Statement or the
Prospectus, or in any amendment or supplement thereto, any material fact
required to be stated therein or necessary to make the statements therein not
misleading, but in each case only to the extent that the untrue statement or
alleged untrue statement or omission or alleged omission was made in reliance
upon and in conformity with written information concerning such Underwriter
furnished to the Company through the Representatives by or on behalf of that
Underwriter specifically for inclusion therein, which information consists
solely of the information specified in Section 10(f), and shall reimburse the
Company and any such director, officer, Selling Stockholder or controlling
person for any legal or other expenses reasonably incurred by the Company or any
such director, officer, Selling Stockholder or controlling person in connection
with investigating or defending or preparing to defend against any such loss,
claim, damage, liability or action as such expenses are incurred. The foregoing
indemnity agreement is in addition to any liability that any Underwriter may
otherwise have to the Company or any such director, officer, Selling
Stockholder, employee or controlling person.

          (d)     Promptly after receipt by an indemnified party under this
Section 10 of notice of any claim or the commencement of any action, the
indemnified party shall, if a claim in respect thereof is to be made against the
indemnifying party under this Section 10, notify the indemnifying party in
writing of the claim or the commencement of that action; PROVIDED, HOWEVER, that
the failure to notify the indemnifying party shall not relieve it from any
liability which it may have under this Section 10 except to the extent it has
been materially prejudiced by such failure and, PROVIDED FURTHER, HOWEVER, that
the failure to notify the indemnifying party shall not relieve it from any
liability which it may have to an indemnified party otherwise than under this
Section 10. If any such claim or action shall be brought against an indemnified
party, and it shall notify the indemnifying party thereof, the indemnifying
party shall be entitled to participate therein and, to the extent that it
wishes, jointly with any other similarly notified indemnifying party, to assume
the defense thereof with counsel reasonably satisfactory to the indemnified
party. After notice from the indemnifying party to the indemnified party of its
election to assume the defense of such claim or action, the indemnifying party
shall not be liable to

                                       30
<Page>

the indemnified party under this Section 10 for any legal or other expenses
subsequently incurred by the indemnified party in connection with the defense
thereof other than reasonable costs of investigation; PROVIDED, HOWEVER, that
the indemnified party shall have the right to employ counsel to represent
jointly the indemnified party and any other indemnified party and their
respective directors, officers, employees, agents and controlling persons who
may be subject to liability arising out of any claim in respect of which
indemnity may be sought by the indemnified party against the indemnifying party
or parties under this Section 10 if, in the reasonable judgment of the
indemnified party, it is advisable for the indemnified party and any other
indemnified party (including their respective directors, officers, employees,
agents and controlling persons) to be jointly represented by separate counsel,
and in that event the reasonable fees and expenses of such separate counsel
shall be paid by the indemnifying party. No indemnifying party shall (i) without
the prior written consent of the indemnified parties (which consent shall not be
unreasonably withheld), settle or compromise or consent to the entry of any
judgment with respect to any pending or threatened claim, action, suit or
proceeding in respect of which indemnification or contribution may be sought
hereunder (whether or not the indemnified parties are actual or potential
parties to such claim or action) unless such settlement, compromise or consent
includes an unconditional release of each indemnified party from all liability
arising out of such claim, action, suit or proceeding and does not include any
findings of fact or admissions of fault or culpability as to the indemnified
party, or (ii) be liable for any settlement of any such action effected without
its written consent (which consent shall not be unreasonably withheld), but if
settled with the consent of the indemnifying party or if there be a final
judgment of the plaintiff in any such action, the indemnifying party agrees to
indemnify and hold harmless any indemnified party from and against any loss or
liability by reason of such settlement or judgment (subject, in the case of
judgments, to the term, conditions and limitations of this Section 10).

          (e)     If the indemnification provided for in this Section 10 shall
for any reason be unavailable to or insufficient to hold harmless an indemnified
party under Section 10(a), 10(b) or 10(c) in respect of any loss, claim, damage
or liability, or any action in respect thereof, referred to therein, then each
indemnifying party shall, in lieu of indemnifying such indemnified party,
contribute to the amount paid or payable by such indemnified party as a result
of such loss, claim, damage or liability, or action in respect thereof, (i) in
such proportion as shall be appropriate to reflect the relative benefits
received by the Company and the Selling Stockholders on the one hand and the
Underwriters on the other from the offering of the Shares or (ii) if the
allocation provided by clause (i) above is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause (i) above but also the relative fault of the Company and
the Selling Stockholders on the one hand and the Underwriters on the other with
respect to the statements or omissions which resulted in such loss, claim,
damage or liability, or action in respect thereof, as well as any other relevant
equitable considerations. The relative benefits received by the Company and the
Selling Stockholders on the one hand and the Underwriters on the other with
respect to such offering shall be deemed to be in the same proportion as the
total net proceeds from

                                       31
<Page>

the offering of the Shares purchased under this Agreement (before deducting
expenses) received by the Company and the Selling Stockholders, on the one hand,
and the total underwriting discounts and commissions received by the
Underwriters with respect to the Shares purchased under this Agreement, on the
other hand, bear to the total gross proceeds from the offering of the Shares
under this Agreement, in each case as set forth in the table on the cover page
of the Prospectus. The relative fault shall be determined by reference to
whether the untrue or alleged untrue statement of a material fact or omission or
alleged omission to state a material fact relates to information supplied by the
Company, the Selling Stockholders or the Underwriters, the intent of the parties
and their relative knowledge, access to information and opportunity to correct
or prevent such statement or omission. The Company, the Selling Stockholders and
the Underwriters agree that it would not be just and equitable if contributions
pursuant to this Section 10(e) were to be determined by pro rata allocation
(even if the Underwriters were treated as one entity for such purpose) or by any
other method of allocation which does not take into account the equitable
considerations referred to herein. The amount paid or payable by an indemnified
party as a result of the loss, claim, damage or liability, or action in respect
thereof, referred to above in this Section 10 shall be deemed to include, for
purposes of this Section 10(e), any legal or other expenses reasonably incurred
by such indemnified party in connection with investigating or defending or
preparing to defend any such action or claim. Notwithstanding the provisions of
this Section 10(e), (i) no Underwriter shall be required to contribute any
amount in excess of the amount by which the total price at which the Shares
underwritten by it and distributed to the public was offered to the public
exceeds the amount of any damages which such Underwriter has otherwise paid or
become liable to pay by reason of any untrue or alleged untrue statement or
omission or alleged omission and (ii) no Selling Stockholder shall be required
to contribute any amount in excess of the amount by which the aggregate purchase
price, less underwriting discounts and commissions, received by such Selling
Stockholder from the sale of Shares exceeds the amount of any damages which such
Selling Stockholder has otherwise paid or become liable to pay by reason of any
untrue or alleged untrue statement or omission or alleged omission. 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. The Underwriters' obligations
to contribute as provided in this Section 10(e) are several in proportion to
their respective underwriting obligations and not joint. The Selling
Stockholders' obligations to contribute as provided in this Section 10(e) are
several in proportion to the number of Shares to be sold by each of them
hereunder and not joint.

          (f)     The Underwriters severally confirm and the Company and the
Selling Stockholders acknowledge that (i) the statements with respect to the
public offering of the Shares by the Underwriters set forth on the cover page of
the Prospectus, and (ii) the second paragraph in the subsection entitled
"Commissions and Expenses," the third sentence in the subsection entitled
"Offering Price Determination," the first, second and fourth paragraphs under
the subsection entitled "Stabilization, Short Positions and Penalty Bids"
(except as it relates to statements or actions of the Company), the

                                       32
<Page>

subsection entitled "Electronic Distribution" (except as it relates to
statements or actions of the Company), and the subsection entitled
"Discretionary Sales," in each case under the caption "Underwriting" in, the
Prospectus are correct and constitute the only information concerning such
Underwriters furnished in writing to the Company by or on behalf of the
Underwriters specifically for inclusion in the Registration Statement and the
Prospectus.

     SECTION 11.  DEFAULTING UNDERWRITERS.

If, on any Delivery Date, any Underwriter defaults in the performance of its
obligations under this Agreement, the remaining non-defaulting Underwriters
shall be obligated to purchase the Shares which the defaulting Underwriter
agreed but failed to purchase on such Delivery Date in the respective
proportions which the number of shares of the Firm Shares set forth opposite the
name of each remaining non-defaulting Underwriter in SCHEDULE 1 hereto bears to
the total number of shares of the Firm Shares set forth opposite the names of
all the remaining non-defaulting Underwriters in SCHEDULE 1 hereto; provided,
however, that the remaining non-defaulting Underwriters shall not be obligated
to purchase any of the Shares on such Delivery Date if the total number of
Shares which the defaulting Underwriter or Underwriters agreed but failed to
purchase on such date exceeds 9.09% of the total number of Shares to be
purchased on such Delivery Date, and any remaining non-defaulting Underwriter
shall not be obligated to purchase more than 110% of the number of Shares which
it agreed to purchase on such Delivery Date pursuant to the terms of Section 3.
If the foregoing maximums are exceeded, the remaining non-defaulting
Underwriters, or those other underwriters satisfactory to the Representatives
who so agree, shall have the right, but shall not be obligated, to purchase, in
such proportion as may be agreed upon among them, all the Shares to be purchased
on such Delivery Date. If the remaining Underwriters or other underwriters
satisfactory to the Representatives do not elect to purchase the Shares which
the defaulting Underwriter or Underwriters agreed but failed to purchase on such
Delivery Date, this Agreement shall terminate without liability on the part of
any non-defaulting Underwriter or the Company or the Selling Stockholders,
except that the Company, the Selling Stockholders and the Underwriters will
continue to be liable for the payment of expenses to the extent set forth in
Sections 8 and 13. As used in this Agreement, the term "UNDERWRITER" includes
(along with the parties mentioned in SCHEDULE 1), for all purposes of this
Agreement unless the context requires otherwise, any party not listed in
SCHEDULE 1 hereto who, pursuant to this Section 11, purchases Shares that a
defaulting Underwriter agreed but failed to purchase.

Nothing contained herein shall relieve a defaulting Underwriter of any liability
it may have to the Company and the Selling Stockholders for damages caused by
its default. If other underwriters are obligated or agree to purchase the Shares
of a defaulting Underwriter, either the Representatives or the Company may
postpone the Delivery Date for up to seven full business days in order to effect
any changes in the opinion of counsel for the Company or counsel for the
Underwriters that may be necessary in the Registration Statement, the Prospectus
or in any other document or arrangement.

                                       33
<Page>

     SECTION 12.  TERMINATION. The obligations of the Underwriters hereunder
may be terminated by the Representatives by notice given to and received by the
Company prior to delivery of and payment for the Firm Shares if, prior to that
time, any of the events described in Sections 9(l) or 9(m), shall have occurred
such that the conditions set forth in such Sections shall not be satisfied, or
if the Underwriters shall decline to purchase the Shares for any reason
permitted under this Agreement.

     SECTION 13.  REIMBURSEMENT OF UNDERWRITERS' EXPENSES. If the Company or
any Selling Stockholder shall fail to tender the Shares for delivery to the
Underwriters by reason of any failure, refusal or inability on the part of the
Company or such Selling Stockholder to perform any agreement on its part to be
performed, or because any other condition of the Underwriters' obligations
hereunder required to be fulfilled by the Company or such Selling Stockholder
(including, without limitation, with respect to the Transactions) is not
fulfilled, the Company or such Selling Stockholder, as the case may be, will
reimburse the Underwriters for all reasonable out-of-pocket expenses (including
fees and disbursements of counsel) incurred by the Underwriters in connection
with this Agreement and the proposed purchase of the Shares, and upon demand
after the provision by the Representatives of reasonable documentation thereof,
the Company or such Selling Stockholder, as the case may be, shall pay the full
amount thereof to the Representatives, provided that if both the Company and
such Selling Stockholder shall have failed to tender the Shares for delivery,
such payment shall be made pro rata based upon the number of Shares to be sold
by such party. If this Agreement is terminated pursuant to Section 11 by reason
of the default of one or more Underwriters, neither the Company nor any Selling
Stockholder shall be obligated to reimburse any defaulting Underwriter on
account of those expenses.

     SECTION 14.  NOTICES, ETC. All statements, requests, notices and
agreements hereunder shall be in writing, and:

          (a)     if to the Underwriters, shall be delivered or sent by mail,
telex or facsimile transmission (with confirmation of transmission) to Lehman
Brothers Inc., 745 Seventh Avenue, 19th Floor, New York, New York 10019,
Attention: Syndicate Registration (Fax: (646) 497-4815), with a copy, in the
case of any notice pursuant to Section 10(d), to the Director of Litigation,
Office of the General Counsel, Lehman Brothers Inc., 399 Park Avenue, 10th
Floor, New York, NY 10022 (Fax: (212) 520-0421), and with a copy to Wilson
Sonsini Goodrich & Rosati, Professional Corporation, 650 Page Mill Road, Palo
Alto, California, 94304, Attention: Matthew W. Sonsini (Fax: (650) 493-6811);

          (b)     if to the Company, shall be delivered or sent by mail or
facsimile transmission (with confirmation of transmission) to the address of the
Company set forth in the Registration Statement, Attention: President and Chief
Executive Officer (Fax: (978) 250-3373), with a copy to Foley Hoag LLP, World
Trade Center West, 155 Seaport Boulevard, Boston, Massachusetts 02210, Attention
Robert W. Sweet, Jr. (Fax: (617) 832-7000);

                                       34
<Page>

          (c)     if to any Selling Stockholder, shall be delivered or sent by
mail or facsimile transmission (with confirmation of transmission) to such
Selling Stockholder at the address set forth on SCHEDULE 2 hereto;

          (d)     provided, however, that any notice to an Underwriter pursuant
to Section 10(d) shall be delivered or sent by mail, telex or facsimile
transmission to such Underwriter at its address set forth in its acceptance
telex to the Representatives, which address will be supplied to any other party
hereto by the Representatives upon request. Any such statements, requests,
notices or agreements shall take effect at the time of receipt thereof. The
Company shall be entitled to act and rely upon any request, consent, notice or
agreement given or made on behalf of the Underwriters or the Representatives by
Lehman Brothers Inc.

          (e)     The Underwriters, the Company and any Selling Stockholder may
change the address for delivery of notice (including telex and facsimile
numbers) by giving notice thereof to the other parties.

     SECTION 15.  PERSONS ENTITLED TO BENEFIT OF AGREEMENT. This Agreement
shall inure to the benefit of and be binding upon the Underwriters, the Company,
the Selling Stockholders and their respective successors, heirs, executors,
administrators and legal representatives. This Agreement and the terms and
provisions hereof are for the sole benefit of only those persons, except that
(a) the representations, warranties, indemnities and agreements of the Company
and the Selling Stockholders contained in this Agreement shall also be deemed to
be for the benefit of directors, officers, employees, agents of the Underwriters
and the person or persons, if any, who control any Underwriter within the
meaning of Section 15 of the Securities Act and (b) the indemnity agreement of
the Underwriters contained in Section 10(c) of this Agreement shall be deemed to
be for the benefit of directors of the Company, officers of the Company who have
signed the Registration Statement, the Selling Stockholders and any person
controlling the Company or any Selling Stockholder within the meaning of Section
15 of the Securities Act. Nothing in this Agreement is intended or shall be
construed to give any person, other than the persons referred to in this Section
15, any legal or equitable right, remedy or claim under or in respect of this
Agreement or any provision contained herein.

     SECTION 16. NO FIDUCIARY DUTY. Notwithstanding any preexisting relationship
, advisory or otherwise, between the parties or any oral representations or
assurances previously or subsequently made by the Underwriters, the Company and
the Selling Stockholders acknowledge and agree that in connection with the
offering: (a) there exists no fiduciary or agency relationship between the
Company or Selling Stockholders, on the one hand, and the Underwriters, on the
other; (b) the relationship between the Company and the Selling Stockholders, on
the one hand, and the Underwriters, on the other, is entirely and solely
commercial, based on arms-length negotiations, and the Underwriters are not
acting as advisors, expert or otherwise, to either the Company or the Selling
Stockholders; (c) notwithstanding anything in this Agreement to the contrary,
the Company and the Selling Stockholders acknowledge that

                                       35
<Page>

the Underwriters may have financial interests in connection with the offering in
addition to the difference between the price to the public and the purchase
price paid to the Company and the Selling Stockholders, respectively, by the
Underwriters for the shares, and the Underwriters have no obligation to
disclose, or account to the Company or the Selling Stockholders for, any of such
additional financial interests. The Company and the Selling Stockholders hereby
waive and release, to the fullest extent permitted by law, any claims that the
Company or the Selling Stockholders may have against the Underwriters with
respect to any breach or alleged breach of fiduciary duty in connection with the
Transactions.

     SECTION 17.  SURVIVAL. The respective indemnities, representations,
warranties and agreements of the Company, the Selling Stockholders and the
Underwriters contained in this Agreement or made by or on behalf on them,
respectively, pursuant to this Agreement, shall survive the delivery of and
payment for the Shares and shall remain in full force and effect, regardless of
any investigation made by or on behalf of any of them or any person controlling
any of them.

     SECTION 18.  DEFINITION OF THE TERMS "BUSINESS DAY" AND "SUBSIDIARY".
For purposes of this Agreement, (a) "BUSINESS DAY" means each Monday, Tuesday,
Wednesday, Thursday or Friday which is not a day on which banking institutions
in New York are generally authorized or obligated by law or executive order to
close and (b) "SUBSIDIARY" has the meaning set forth in Rule 405 of the Rules
and Regulations.

     SECTION 19.  GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with the laws of New York.

     SECTION 20.  COUNTERPARTS. This Agreement may be executed in one or
more counterparts and, if executed in more than one counterpart, the executed
counterparts shall each be deemed to be an original but all such counterparts
shall together constitute one and the same instrument.

     SECTION 21.  HEADINGS. The headings herein are inserted for convenience
of reference only and are not intended to be part of, or to affect the meaning
or interpretation of, this Agreement.

                            [SIGNATURE PAGE FOLLOWS]

                                       36
<Page>

If the foregoing correctly sets forth the agreement among the Company, the
Selling Stockholders and the Underwriters, please indicate your acceptance in
the space provided for that purpose below.

                                   Very truly yours,


                                   HITTITE MICROWAVE CORPORATION


                                   By:
                                       -----------------------------------------
                                   Name:
                                         ---------------------------------------
                                   Title:
                                          --------------------------------------


                                   THE SELLING STOCKHOLDERS LISTED IN SCHEDULE 2
                                   TO THE AGREEMENT


                                   By:
                                      ------------------------------------------
                                       Attorney-in-Fact


Accepted:

LEHMAN BROTHERS INC.
NEEDHAM & COMPANY, LLC
PIPER JAFFRAY & CO.
THOMAS WEISEL PARTNERS LLC

For themselves and as Representatives
of the several Underwriters listed
in Schedule 1 hereto

By: LEHMAN BROTHERS INC.

By:
    -----------------------------------------
Name:
      ---------------------------------------
Title:
       --------------------------------------

<Page>

                                   SCHEDULE 1

<Table>
<Caption>
                                                         NUMBER OF SHARES OF
                                                           FIRM SHARES TO BE
UNDERWRITER                                                        PURCHASED
----------------------------------------------------------------------------
<S>                                                                <C>
Lehman Brothers Inc.                                               1,935,000
Needham & Company, LLC                                               788,334
Piper Jaffray & Co.                                                  788,333
Thomas Weisel Partners LLC                                           788,333
Chatsworth Securities LLC                                             50,000
National Financial Markets Group, a Division
   of National Financial Services LLC                                 50,000
Oppenheimer & Co. Inc.                                                50,000
Raymond James & Associates, Inc.                                      50,000
                                       TOTAL                       4,500,000
</Table>

<Page>

                                   SCHEDULE 2

<Table>
<Caption>
     NAME OF SELLING
STOCKHOLDER AND ADDRESS(1)                      FIRM SHARES TO BE SOLD
----------------------------------------------------------------------
<S>                                                      <C>
Summit Ventures V, L.P.                                  543,863
222 Berkeley Street, 18th Floor
Boston, Massachusetts, 02116

Summit V Companion Fund, L.P.                            187,369
222 Berkeley Street, 18th Floor
Boston, Massachusetts, 02116

Summit V Advisors                                         41,903
Fund (QP), L.P.
222 Berkeley Street, 18th Floor
Boston, Massachusetts, 02116

Summit V Advisors Fund, L.P.                              12,805
222 Berkeley Street, 18th Floor
Boston, Massachusetts, 02116

Summit Investors III, L.P.                                14,060
222 Berkeley Street, 18th Floor
Boston, Massachusetts, 02116

Dr. S. Francis Paik                                      277,778
16 Minebrook Road
Lincoln, MA 01773

George F. Paik Irrevocable Trust                         222,222
15 Overlook Drive
Newtown, CT 06470

Richard A. Paik Irrevocable Trust                        277,778
13 Commonwealth Avenue
Swampscott, MA 01907

Carol A. Paik Irrevocable Trust                          222,222
670 West End Avenue
New York, NY 10025

                            TOTAL                      1,800,000
</Table>

(1). Each Selling Stockholder has appointed Stephen G. Daly and William W.
Boecke, and each of them, as Attorneys-in-Fact for such Selling Stockholder.

<Page>

                                    EXHIBIT A

 Form of Opinion of Iandiorio & Teska, Intellectual Property Counsel for Company

                                                  , 2005

LEHMAN BROTHERS INC.
NEEDHAM & COMPANY, LLC
PIPER JAFFRAY & CO.
THOMAS WEISEL PARTNERS LLC
     As Representatives of the several
     Underwriters
c/o Lehman Brothers Inc.
745 Seventh Avenue
New York, New York 10019


              Re: Intellectual Property of Hittite Microwave Corp.
                  Our reference No.: HIT-100J

Ladies and Gentlemen:

           We have been retained by Hittite Microwave Corp. (the "Company") with
respect to its intellectual property matters, including its patent matters. We
have been asked by the Company to provide an opinion concerning its patents.

           The status of the Company's patents and patent applications, as of
April 20, 2005, is shown in Exhibit A attached hereto. As indicated therein, the
Company has 9 issued U.S. patents, 1 pending U.S. patent applications, 2 issued
foreign patents and 0 pending foreign patent applications.

           Exhibit A to this opinion is a list of the Company's patents and
pending patent applications (the "Patent Rights") which, to the best of our
knowledge, are owned by the Company. To the best of our knowledge either (a) an
assignment from the inventor(s) to the Company has been recorded in the United
States Patent and Trademark Office or in other applicable foreign jurisdictions,
or (b) the inventor(s) are under obligation of assignment to the Company, and an
assignment will be recorded in the United States Patent and Trademark Office or
in other applicable foreign jurisdictions. To the best of our knowledge, there
are no claims to any ownership interests or liens on any of the Patent Rights by
any party other than the Company. To the best of our knowledge, the Company has
not licensed the rights to use any of its patents.

           We are unaware of any facts that would lead us to believe that: (a)
any of the patents, which are listed in Exhibit A of this opinion, are invalid,
(b) any patent that may be issued in respect of a patent application, which is
listed in Exhibit A of this opinion, would be invalid, or

<Page>

(c) any material defects of form exist in the preparation or filing of any of
the patents and patent applications which are listed in Exhibit A of this
opinion.

           To the best of our knowledge, for each of the U.S. patent
applications filed and prosecuted by us reflected in Exhibit A, we have
disclosed or intend to disclose to the United States Patent and Trademark Office
all information known to us and believed by us to be material to patentability
as required under 37 C.F.R. Section 1.56.

           To the best of our knowledge, there are no pending or threatened
legal or governmental proceedings relating to the patents and pending patent
applications reflected in Exhibit A, other than the proceedings before the
United States Patent and Trademark Office and foreign patent offices that are
carried out during the course of prosecution.

           Other than any other actions, suits, proceedings or claims that have
been resolved or are immaterial, to the best of our knowledge the Company has
not received any claim of infringement of any patents held by others, and to our
knowledge there is no pending or threatened action, suit, proceeding or claim by
others that the Company is infringing a patent.

           In addition, other than any actions, suits, proceedings or claims
that have been resolved, nothing has come to our attention that has led us to
believe that any patents of others are infringed by the present or future
business of the Company as described in the Prospectus under the caption
"Business." We have read the portions of the Prospectus under the captions "Risk
Factors - Claims that we are infringing third-party intellectual property rights
may result in costly and lengthy litigation that could harm our business", "Risk
Factors -We use a number of specialized technologies, some of which are
patented, to design, develop and manufacture our products. Infringement of our
intellectual property rights could hurt our competitive position, harm our
reputation and adversely affect our results of operations," "Business -
Intellectual Property" and "Business -Litigation." We have considered the
statements contained therein, although we have not independently verified the
accuracy, completeness and fairness of such statements. Based upon and subject
to the foregoing, nothing has come to our attention, as of the date of the
Prospectus and the date hereof, that leads us to believe that the Patent
Information contains an untrue statement of a material fact or omits to state a
material fact in light of the circumstances in which they are made. As of the
date of the Prospectus and the date hereof, we have no reason to believe that
the Patent Information is not in all material respects a fair and accurate
summary of the legal matters, documents and proceedings relating thereto,
insofar as such statements constitute a summary of the Company's patents and
applications and legal proceedings related thereto.

           As used in this letter, "to the best of our knowledge" means this
firm's current knowledge, based upon information received from the Company, as a
consequence of our representation of the Company, and upon the patent
applications filed and prosecuted by us on behalf of the Company. With respect
to ownership of the United States patents, our opinion is based upon our
"knowledge" and upon our review of the United States Patent and Trademark Office
assignee records.

           The statements in this letter with respect to patent infringement and
validity should be understood to involve a complex area of law where reasonable
minds, including those of judges

<Page>

or juries, differ. It should be understood that the opinion set forth above is
as of the date hereof and is not intended as a guarantee of any particular
result or decision.

           We assume no obligation to advise you of any changes to the foregoing
subsequent to the delivery of this letter. Please also note that this opinion is
provided to you only for the specific purpose of assisting you in your
confidential evaluation of the Company. This opinion is not provided for any
other purpose, and you should not provide this opinion or disclose its contents
to any third party without obtaining our prior approval.

                                                    Very truly yours,

<Page>

                                    EXHIBIT B

               Form of Opinion of Counsel for Selling Stockholders

     (i)    Each Selling Stockholder has record ownership of the number of
shares of Common Stock or Series A Preferred Stock set forth opposite the name
of such Selling Stockholder on EXHIBIT A hereto, which shares are represented by
the certificates identified on EXHIBIT A hereto. To our knowledge, each Selling
Stockholder has full power and authority to sell, transfer and deliver the
Shares to be sold by such Selling Stockholder pursuant to the Underwriting
Agreement. Assuming that the Underwriters do not have notice of any adverse
claim (within the meaning of Sections 8-102(a)(1) and 8-105 of the New York
Uniform Commercial Code) to the Shares to be sold by such Selling Stockholder,
upon delivery to the Underwriters of the certificates for such Shares by or on
behalf of such Selling Stockholder duly indorsed in blank or accompanied by duly
executed stock powers in favor of the Underwriters and all applicable stock
transfer stamps against payment therefor as provided in the Underwriting
Agreement, the Underwriters will acquire such Shares free of any adverse claim
(within the meaning of Section 8-102(a)(1) of the New York Uniform Commercial
Code);

     (ii)   Except for the registration of the Shares under the Securities Act
and such consents, approvals, authorizations, orders, filings, registrations or
qualifications as may be required under the Exchange Act, applicable state or
foreign securities laws in connection with the purchase and distribution of the
Shares by the Underwriters, the rules of the Nasdaq Stock Market, Inc. and the
rules of the NASD, to the knowledge of such counsel, no consent, approval,
authorization or order of, or filing with, any federal or Massachusetts court or
governmental agency or body is required for the consummation by each Selling
Stockholder of the transactions contemplated by the Underwriting Agreement,
except for such consents, approvals, authorizations, orders, filings,
registrations or qualifications as have been obtained or made;

     (iii)  The execution, delivery and performance by each Selling Stockholder
of the Underwriting Agreement and the consummation by each Selling Stockholder
of the transactions contemplated thereby will not result in a violation of the
charter or by-laws of such Selling Stockholder, if applicable, or any material
violation of any statute, order, rule or regulation known to such counsel of any
federal or Massachusetts court or governmental agency or body having
jurisdiction over such Selling Stockholder or any of its properties;

     (iv)   Each of the Power of Attorney and the Custody Agreement of each
Selling Stockholder has been duly authorized, executed and delivered by such
Selling Stockholder and constitutes a valid and legally binding obligation of
such Selling Stockholder, enforceable against such Selling Stockholder in
accordance with its terms, subject to bankruptcy, insolvency, fraudulent
transfer, reorganization, moratorium and similar laws of general applicability
relating to or affecting creditors' rights and to general equity principles; and

     (v)    The Underwriting Agreement has been duly authorized by each Selling
Stockholder (other than any Selling Stockholder that is an individual) and has
been duly executed and delivered by the Attorneys on behalf of each Selling
Stockholder.