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                                                                   EXHIBIT 10.19





                               DIGIRAD CORPORATION

                AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT

                                 August 23, 2001


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                           INVESTORS' RIGHTS AGREEMENT

         This AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT (this
"Agreement") is made as of the 23rd day of August, 2001, by and between
Digirad Corporation, a Delaware corporation (the "Company"), holders of a
majority of the shares held by the founders of the Company identified on
SCHEDULE A attached hereto under the heading "Founders" (the "Founders"),
holders of a majority of the Preferred Stock of the Company identified on
SCHEDULE A attached hereto under the heading "Existing Investors" (the
"Existing Investors") and each of the purchasers of the Series F Preferred
Stock of the Company identified on SCHEDULE A attached hereto under the
heading "New Investors" and Silicon Valley Bank (collectively, the "New
Investors"). The Existing Investors and the New Investors are collectively
referred to herein as, individually, an "Investor" and collectively, the
"Investors."

                                    RECITALS

         A. The Company has previously sold and issued shares of its capital
stock to the Founders and to the Existing Investors, pursuant to which the
Founders and the Existing Investors have become parties to that certain
Investors' Rights Agreement dated November 10, 2000, as amended (the
"Investors' Rights Agreement");

         B. The Company desires to sell and issue shares of its Series F
Preferred Stock to the New Investors pursuant to that certain Series F
Preferred Stock Purchase Agreement of even date herewith (the "Purchase
Agreement"); and

         C. As an inducement to the New Investors to purchase shares of its
Series F Preferred Stock, the Company, the Founders and the Existing
Investors all desire to completely amend and restate the Investors' Rights
Agreement pursuant to Section 5.7 with respect to the matters set forth
therein.

         NOW, THEREFORE, in consideration of the foregoing and of the mutual
promises and covenants contained herein it is hereby agreed:

1.       COVENANTS OF THE COMPANY.

                  1.1 BOARD EXPENSES. The Company shall reimburse the Board
members for all reasonable out-of-pocket travel and expenses incurred by such
directors in attending the meetings of the Board and committees of the Board
of which any such director is a member.

                  1.2 RIGHT OF FIRST OFFER. Subject to the terms and
conditions specified in this Section 1.2, the Company hereby grants to
Investors, and to Jack F. Butler, Sr. and Clinton L. Lingren (and their
respective transferees) (collectively, the "Founders" and each an "Offeree"),
a right of first offer with respect to future sales by the Company of its
Shares (as hereinafter defined). Investors shall be entitled to apportion the
right of the first offer hereby granted among themselves and their partners
and affiliates in such proportions as they deem appropriate.

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                  Each time the Company proposes to offer any shares of, or
securities convertible into or exercisable for, any class of its capital
stock (the "Shares"), the Company shall first make an offering of such Shares
to each Offeree in accordance with the following provisions:

                  (a) The Company shall deliver a notice by certified mail
("Notice") to the Offeree stating (i) its bona fide intention to offer or
issue such Shares, (ii) the number of such Shares to be offered, and (iii)
the price, if any, for which it proposes to offer such Shares.

                  (b) Within 20 calendar days after receipt of the Notice,
the Offeree may elect to purchase or obtain, at the price and on the terms
specified in the Notice, up to that portion of such Shares which equals the
proportion that the number of shares of Common Stock issued and held, or
issuable upon conversion of the Preferred Stock then held, by such Offeree
bears to the total number of shares of outstanding Common Stock and Common
Stock issuable upon conversion of the Preferred Stock then outstanding. The
Company shall promptly in writing, inform each Offeree which purchases all
the shares available to it (a "Fully Exercising Offeree") of any other
Offeree's failure to do likewise. During the 10-day period commencing after
receipt of such information, each Fully Exercising Offeree shall be entitled
to obtain that portion of the shares subject to such right of first refusal
and not subscribed for by the Offerees which is equal to the proportion that
the number of shares of Common Stock issued and held , or issuable upon
conversion of the Preferred Stock then held, by such Fully Exercising Offeree
bears to the total number of shares of Common Stock issued and held, or
issuable upon conversion of the Preferred Stock then held, by all Fully
Exercising Offerees who wish to purchase some of the unsubscribed shares.

                  (c) If all such Shares referred to in the Notice are not
elected to be obtained as provided in subsection 1.2(b) hereof, the Company
may, during the 60-day period following the expiration of the period provided
in subsection 1.2(b) hereof, offer the remaining unsubscribed Shares to any
person or persons at a price not less than that, and upon terms no more
favorable to the offeree than those, specified in the Notice. If the Company
does not enter into an agreement for the sale of the Shares within such
period, or if such agreement is not consummated within 60 days of the
execution thereof, the right provided hereunder shall be deemed to be revived
and such Shares shall not be offered unless first reoffered to the Offerees
in accordance herewith.

                  (d) The right of first offer granted in this Section 1.2
shall not be applicable (i) to the issuance or sale of shares of Common
Stock, or options granted to employees, directors, consultants or advisors of
the Company under stock option and restricted stock purchase agreements
approved by the Board of Directors commencing as of May 1994 (each, an
"Option, and collectively, "Options") or warrants therefor, to employees,
directors, consultants or advisors of the Company, provided each such person
executes an agreement relating to such issuance or sale in substantially the
form as approved by the Company's Board of Directors, (ii) to the issuance
and sale of the Company's securities to a corporation, partnership,
educational institution or other entity in connection with a research and
development partnership or licensing or other collaborative arrangement
between the Company and such institution or entity, (iii) to or after
consummation of a bona fide, firmly underwritten public offering of shares of
the Company's Common Stock registered under the Securities Act of 1933, as
amended (the "Securities Act"), which results in gross proceeds of at least
$15,000,000 at a price per share of


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at least $7.50 (adjusted for any subsequent stock splits, stock dividends or
other recapitalizations), (iv) to the issuance of securities pursuant to the
conversion or exercise of convertible or exercisable securities, (v) to the
issuance of securities in connection with a bona fide business acquisition of
or by the Company, whether by merger, consolidation, sale of assets, sale or
exchange of stock or otherwise, and (vi) to the issuance of securities in
connection with credit agreements with equipment lessors or commercial
lenders.

                  (e) Any term of this Section 1.2 may be amended and the
observance of any term of this Section 1.2 may be waived (either generally or
in a particular instance and either retroactively or prospectively), only
with the written consent of (i) the Company, (ii) the holders of a majority
of the shares held by the Founders, and (iii) the Investors holding of a
majority of the Common Stock issued or issuable upon conversion of the Series
A Preferred Stock, Series B Preferred Stock, Series C Preferred Stock, Series
D Preferred Stock, Series E Preferred Stock and Series F Preferred Stock,
voting as a single class. Any amendment or waiver effected in accordance with
this paragraph shall be binding upon each holder of any securities of the
Company at the time outstanding (including securities into which such
securities are convertible) with rights under this Section 1.2, each future
holder of all such securities, and the Company.

                  1.3 BOARD OBSERVATION RIGHTS. A person beneficially holding
or controlling 300,000 (adjusted for stock splits, reverse stock splits, and
similar changes in capitalization) or more shares of the Company's Series A
Preferred Stock who is not a member of the Company's Board of Directors shall
receive from the Company, with such limitations as are provided herein,
notice of all meetings for the Board of Directors, and such stockholder shall
receive any materials distributed for such meeting and may attend such
meetings; provided, however, that the Company may require as a condition
precedent that such stockholder in requesting to attend any meeting of the
Board of Directors shall agree to hold it in confidence and trust all
information received during or in connection with such meeting and require
that such stockholder sign a confidentiality agreement with the Company and,
provided further, that the Company reserves the right not to provide
information and to exclude such stockholder from any meeting or portion
thereof if attendance at such meeting by such stockholder or dissemination of
any information at such meeting to such stockholder would, in the good faith
judgment of the Board of Directors, result in a conflict of interest. If such
stockholder in his or her good faith judgment believes that an item to be
discussed by the Board of Directors would result in any conflict of interest,
such stockholder shall promptly bring such conflict to the attention of the
stockholder on the Board. In no event shall any such stockholder have the
right to vote at any such meeting or shall any provision of this paragraph
waive any obligation of confidentiality to the Company owed by such
stockholder.

2.       REGISTRATION RIGHTS.

         The Company covenants and agrees as follows:

                  2.1 DEFINITIONS. For purposes of this Section 2:

                  (a) The terms "register," "registered," and "registration"
refer to a registration effected by preparing and filing a registration
statement or similar document in compliance with


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the Securities Act, and the declaration or ordering of effectiveness of such
registration statement or document;

                  (b) The term "Registrable Securities" means (i) the Common
Stock issuable or issued upon conversion of the Series A Preferred Stock,
Series B Preferred Stock, Series C Preferred Stock, Series D Preferred Stock,
Series E Preferred Stock and Series F Preferred Stock and (ii) any Common
Stock of the Company issued as (or issuable upon the conversion or exercise
of any warrant, right or other security which is issued as) a dividend or
other distribution with respect to, or in exchange for or in replacement of,
such Series A Preferred Stock, Series B Preferred Stock, Series C Preferred
Stock, Series D Preferred Stock, Series E Preferred Stock, Series F Preferred
Stock or Common Stock, excluding in all cases, however, any Registrable
Securities sold by a person in a transaction in which such person's
registration rights are not assigned;

                  (c) The number of shares of "Registrable Securities then
outstanding" shall be determined by the number of shares of Common Stock
outstanding which are, and the number of shares of Common Stock issuable
pursuant to then exercisable or convertible securities which are exercisable
or convertible into, Registrable Securities;

                  (d) The term "Holder" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with Section 2.13 hereof; and

                  (e) The term "Form S-3" means such form under the
Securities Act as in effect on the date hereof or any registration form under
the Securities Act subsequently adopted by the SEC in lieu of Form S-3 which
permits inclusion or incorporation of substantial information by reference to
other documents filed by the Company with the SEC.

                  2.2 REQUEST FOR REGISTRATION.

                  (a) If the Company shall receive at any time after the
earlier of (i) January 1, 2002 or (ii) one year after the effective date of
the first registration statement for a public offering of securities of the
Company (other than a registration statement relating either to the sale of
securities to employees of the Company pursuant to a stock option, stock
purchase or similar plan or a SEC Rule 145 transaction), a written request
from the Holders of at least 30% of the Registrable Securities then
outstanding (or at least 25% of the Registrable Securities then outstanding
if such request is made following any Closing of the offering referred to in
subsection (ii) of this Section 2.2(a)) that the Company file a registration
statement under the Securities Act covering the registration of at least 20%
of the Registrable Securities then outstanding (or a lesser percent if the
anticipated aggregate offering price, net of underwriting discounts and
commissions, would exceed $15,000,000), then the Company shall, within 10
days of the receipt thereof, give written notice of such request to all
Holders and shall, subject to the limitations of subsection 2.2(b), file as
soon as practicable, and in any event within 60 days of the receipt of such
request, a registration statement under the Securities Act covering all
Registrable Securities which the Holders request to be registered within 20
days of the mailing of such notice by the Company in accordance with Section
5.5.

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                  (b) If the Holders initiating the registration request
hereunder (the "Initiating Holders") intend to distribute the Registrable
Securities covered by their request by means of an underwriting, they shall
so advise the Company as a part of their request made pursuant to this
Section 2.2 and the Company shall include such information in the written
notice referred to in subsection 2.2(a). In such event, the right of any
Holder to include such Holder's Registrable Securities in such registration
shall be conditioned upon such Holder's participation in such underwriting
and the inclusion of such Holder's Registrable Securities in the underwriting
(unless otherwise mutually agreed by a majority in interest of the Initiating
Holders and such Holder) to the extent provided herein. All Holders proposing
to distribute their securities through such underwriting shall (together with
the Company as provided in subsection 2.4(e)) enter into an underwriting
agreement in customary form with the underwriter or underwriters selected for
such underwriting by the Company and consented to by a majority in interest
of the Holders proposing to distribute securities through such underwriting
(which consent shall not be unreasonably withheld). Notwithstanding any other
provision of this Section 2.2, if the underwriter advises the Company and the
Initiating Holders in writing that marketing factors require a limitation of
the number of shares to be underwritten, then the Company shall so advise all
Holders of Registrable Securities which would otherwise be underwritten
pursuant hereto, and the number of shares of Registrable Securities that may
be included in the underwriting shall be allocated among all Holders thereof,
including the Initiating Holders, in proportion (as nearly as practicable) to
the number of Registrable Securities of the Company owned by each Holder
including securities in the underwriting.

                  (c) The Company is obligated to effect only two such
registrations pursuant to this Section 2.2; provided, however, that the
Company shall not be obligated to effect a registration pursuant to this
Section 2.2 if within the 12 months immediately preceding a request hereunder
the Company has effected a demand registration under this Section 2.2.

                  (d) Notwithstanding the foregoing, if the Company shall
furnish to Holders requesting a registration statement pursuant to this
Section 2.2 a certificate signed by the President of the Company stating that
in the good faith judgment of the Board of Directors of the Company it would
be seriously detrimental to the Company and its stockholders for such
registration statement to be filed and it is therefore essential to defer the
filing of such registration statement, the Company shall have the right to
defer such filing for a period of not more than 90 days after receipt of the
request of the Initiating Holders; provided, however, that the Company may
not utilize this right more than twice in the aggregate and not more than
once in any 12-month period.

                  2.3 COMPANY REGISTRATION. If (but without any obligation to
do so) the Company proposes to register (including for this purpose a
registration effected by the Company for stockholders other than the Holders)
any of its stock or other securities under the Securities Act in connection
with the public offering of such securities solely for cash (other than a
registration relating solely to the sale of securities to participants in a
Company stock plan, or a registration on any form which does not include
substantially the same information as would be required to be included in a
registration statement covering the sale of the Registrable Securities), the
Company shall, at such time, promptly give each Holder written notice of such
registration. Upon the written request of each Holder given within 20 days
after mailing of such


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notice by the Company in accordance with Section 5.5, the Company shall,
subject to the provisions of Section 2.8, cause to be registered under the
Securities Act all of the Registrable Securities that each such Holder has
requested to be registered. No Holder shall have any rights under this
Section 2.3 unless it is the owner of at least 200,000 shares of the
Company's Common Stock either directly or through ownership of Preferred
Stock, as adjusted to reflect any stock splits, stock dividends or other
recapitalizations.

                  2.4 OBLIGATIONS OF THE COMPANY. Whenever required under
this Section 2 to effect the registration of any Registrable Securities, the
Company shall, as expeditiously as reasonably possible:

                  (a) Prepare and file with the Securities and Exchange
Commission (the "SEC") a registration statement with respect to such
Registrable Securities and use its reasonable efforts to cause such
registration statement to become effective, and, upon the request of the
Holders of a majority of the Registrable Securities registered thereunder,
keep such registration statement effective for up to 120 days.

                  (b) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in
connection with such registration statement as may be necessary to comply
with the provisions of the Securities Act with respect to the disposition of
all securities covered by such registration statement.

                  (c) Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.

                  (d) Use its reasonable efforts to register and qualify the
securities covered by such registration statement under such other securities
or blue sky laws of such jurisdictions as shall be reasonably requested by
the Holders, provided that the Company shall not be required in connection
therewith or as a condition thereto to qualify to do business or to file a
general consent to service of process in any such states or jurisdictions.

                  (e) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual
and customary form, with the managing underwriter of such offering. Each
Holder participating in such underwriting shall also enter into and perform
its obligations under such an agreement.

                  (f) Notify each Holder of Registrable Securities covered by
such registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any
event as a result of which the prospectus included in such registration
statement, as then in effect, includes an untrue statement of a material fact
or omits to state a material fact required to be stated therein or necessary
to make the statements therein not misleading in the light of the
circumstances then existing.

                  (g) Furnish, at the request of any Holder requesting
registration of Registrable


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Securities pursuant to this Section 2, on the date that such Registrable
Securities are delivered to the underwriters for sale in connection with a
registration pursuant to this Section 2, if such securities are being sold
through underwriters, or, if such securities are not being sold through
underwriters, on the date that the registration statement with respect to
such securities becomes effective, (i) an opinion, dated such date, of the
counsel representing the Company for the purposes of such registration, in
form and substance as is customarily given to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities and (ii) a letter dated
such date, from the independent certified public accountants of the Company,
in form and substance as is customarily given by independent certified public
accountants to underwriters in an underwritten public offering, addressed to
the underwriters, if any, and to the Holders requesting registration of
Registrable Securities.

         2.5 FURNISH INFORMATION.

                  (a) It shall be a condition precedent to the obligations of
the Company to take any action pursuant to this Section 2 that the selling
Holders shall furnish to the Company such information regarding themselves,
the Registrable Securities held by them, and the intended method of
disposition of such securities as shall be required to effect the
registration of the Registrable Securities.

                  (b) The Company shall have no obligation with respect to
any registration requested pursuant to Section 2.2 or Section 2.12 if, due to
the operation of subsection 2.5(a), the number of shares or the anticipated
aggregate offering price of the Registrable Securities to be included in the
registration does not equal or exceed the number of shares or the anticipated
aggregate offering price required to originally trigger the Company's
obligation to initiate such registration as specified in subsection 2.2(a) or
subsection 2.12(b)(ii), whichever is applicable.

                  2.6 EXPENSES OF DEMAND REGISTRATION. The Company shall bear
and pay all expenses other than underwriting discounts and commissions
incurred in connection with registrations, filings or qualifications pursuant
to Section 2.2, including (without limitation) all registration, filing and
qualification fees, printers' and accounting fees, fees and disbursements of
counsel for the Company and the reasonable fees and expenses of one counsel
for the selling Holders selected by them; provided, however, that the Company
shall not be required to pay for any expenses of any registration proceeding
begun pursuant to Section 2.2 if the registration request is subsequently
withdrawn at the request of the Holders of a majority of the Registrable
Securities to be registered (in which case all participating Holders shall
bear such expenses), unless the Holders of a majority of the Registrable
Securities agree to forfeit their right to one demand registration pursuant
to Section 2.2; provided further, however, that if at the time of such
withdrawal, the Holders have learned of a material adverse change in the
condition, business or prospects of the Company from that known to the
Holders at the time of their request, then the Holders shall not be required
to pay any of such expenses and shall retain their rights pursuant to Section
2.2.

                  2.7 EXPENSES OF COMPANY REGISTRATION. The Company shall
bear and pay all expenses incurred in connection with any registration,
filing or qualification of Registrable


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Securities with respect to the registrations pursuant to Section 2.3 for each
Holder (which right may be assigned as provided in Section 2.13), including
(without limitation) all registration, filing and qualification fees,
printers' and accounting fees relating or apportionable thereto and the
reasonable fees and expenses of one counsel for the selling Holders selected
by them, but excluding underwriting discounts and commissions relating to
Registrable Securities.

                  2.8 UNDERWRITING REQUIREMENTS. In connection with any
offering involving an underwriting of shares being issued by the Company, the
Company shall not be required under Section 2.3 to include any of the
Holders' securities in such underwriting unless they accept the terms of the
underwriting as agreed upon between the Company and the underwriters selected
by it, and then only in such quantity as will not, in the opinion of the
underwriters, jeopardize the success of the offering by the Company. If the
total number of securities, including Registrable Securities, requested by
stockholders to be included in such offering exceeds the number of securities
sold other than by the Company that the underwriters reasonably believe
compatible with the success of the offering, then the Company shall be
required to include in the offering only that number of such securities,
including Registrable Securities, which the underwriters believe will not
jeopardize the success of the offering (the securities so included to be
apportioned pro rata among the selling stockholders according to the total
number of securities entitled to be included therein owned by each selling
stockholder or in such other proportions as shall mutually be agreed to by
such selling stockholders) but in no event shall the number of securities of
the selling Holders included in the offering be reduced below 30% of the
total number of securities included in such offering, unless such offering is
the initial public offering of the Company's securities in which case the
selling stockholders may be excluded if the underwriters make the
determination described above and no other stockholder's securities are
included.

                  2.9 DELAY OF REGISTRATION. No Holder shall have any right
to obtain or seek an injunction restraining or otherwise delaying any such
registration as the result of any controversy that might arise with respect
to the interpretation or implementation of this Section 2.

                  2.10 INDEMNIFICATION. In the event any Registrable
Securities are included in a registration statement under this Section 2:

                  (a) To the extent permitted by law, the Company will
indemnify and hold harmless each Holder, the officers and directors of each
Holder, any underwriter (as defined in the Securities Act) for such Holder
and each person, if any, who controls such Holder or underwriter within the
meaning of the Securities Act or the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), against any losses, claims, damages or
liabilities (joint or several) to which they may become subject under the
Securities Act, the Exchange Act or other federal or state law, insofar as
such losses, claims, damages or liabilities (or actions in respect thereof)
arise out of or are based upon any of the following statements, omissions or
violations (each, a "Violation"): (i) any untrue statement or alleged untrue
statement of a material fact contained in such registration statement,
including any preliminary prospectus or final prospectus contained therein or
any amendments or supplements thereto, (ii) the omission or alleged omission
to state therein a material fact required to be stated therein, or necessary
to make the


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statements therein not misleading, or (iii) any violation or alleged
violation by the Company of the Securities Act, the Exchange Act, any state
securities law or any rule or regulation promulgated under the Securities
Act, the Exchange Act or any state securities law; and the Company will
reimburse each such Holder, officer or director, underwriter or controlling
person for any legal or other expenses reasonably incurred by them in
connection with investigating or defending any such loss, claim, damage,
liability or action; provided, however, that the indemnity agreement
contained in this subsection 2.10(a) shall not apply to amounts paid in
settlement of any such loss, claim, damage, liability or action if such
settlement is effected without the consent of the Company (which consent
shall not be unreasonably withheld), nor shall the Company be liable in any
such case for any such loss, claim, damage, liability or action to the extent
that it arises out of or is based upon a Violation which occurs in reliance
upon and in conformity with written information furnished expressly for use
in connection with such registration by any such Holder, officer, director,
underwriter or controlling person.

                  (b) To the extent permitted by law, each selling Holder
will severally and not jointly indemnify and hold harmless the Company, each
of its directors, each of its officers who have signed the registration
statement, each person, if any, who controls the Company within the meaning
of the Securities Act, any underwriter and any other Holder selling
securities in such registration statement or any of its directors or officers
or any person who controls such Holder, against any losses, claims, damages
or liabilities (joint or several) to which the Company or any such director,
officer, controlling person, or underwriter or controlling person, or other
such Holder or director, officer or controlling person may become subject,
under the Securities Act, the Exchange Act or other federal or state law,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereto) arise out of or are based upon any Violation, in each case to the
extent (and only to the extent) that such Violation occurs in reliance upon
and in conformity with written information furnished by such Holder expressly
for use in connection with such registration; and each such Holder will
reimburse any legal or other expenses reasonably incurred by the Company or
any such director, officer, controlling person, underwriter or controlling
person, other Holder, officer, director, or controlling person in connection
with investigating or defending any such loss, claim, damage, liability, or
action; provided, however, that the indemnity agreement contained in this
subsection 2.10(b) shall not apply to amounts paid in settlement of any such
loss, claim, damage, liability or action if such settlement is effected
without the consent of the Holder, which consent shall not be unreasonably
withheld; provided, that, in no event shall any indemnity under this
subsection 2.10(b) exceed the net proceeds (after deducting any discounts or
commissions received by an underwriter in connection with such registration)
from the offering received by such Holder.

                  (c) Promptly after receipt by an indemnified party under
this Section 2.10 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect
thereof is to be made against any indemnifying party under this Section 2.10,
deliver to the indemnifying party a written notice of the commencement
thereof and the indemnifying party shall have the right to participate in,
and, to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume the defense thereof with
counsel mutually satisfactory to the parties; provided, however, that an
indemnified party shall have the right to retain its own counsel, with the
fees and


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expenses to be paid by the indemnifying party, if representation of such
indemnified party by the counsel retained by the indemnifying party would be
inappropriate due to actual or potential differing interests between such
indemnified party and any other party represented by such counsel in such
proceeding. The failure to deliver written notice to the indemnifying party
within a reasonable time of the commencement of any such action shall not
relieve such indemnifying party of its obligations under this Agreement,
except to the extent, but only to the extent, that the indemnifying party's
ability to defend against such action is actually and materially impaired as
a result of the failure to give such notice. The omission to so deliver
written notice to the indemnifying party will not relieve the indemnifying
party of any liability that it may have to any indemnified party otherwise
than under this Section 2.10.

                  (d) If the indemnification provided for in Sections
2.10(a), (b) and (c) is unavailable to an indemnified party under such
Sections (other than by reason of exceptions provided in those Sections) in
respect of any claims referred to in such Sections, then each applicable
indemnifying party, in lieu of indemnifying such indemnified party, shall
contribute to the amount paid or payable by such indemnified party as a
result of such claims in such proportion as is appropriate to reflect the
relative fault of the Company on the one hand and of the Holders of
Registrable Securities on the other in connection with the statements or
omissions which resulted in such claims as well as any other relevant
equitable considerations. The amount paid or payable by a party as a result
of the claims referred to above shall be deemed to include any legal or other
fees or expenses reasonably incurred by such party in connection with
investigating or defending any action or claim. The relative fault of the
Company on the one hand and of the Holders of Registrable Securities on the
other shall be determined by reference to, among other things, whether the
applicable misstatement or alleged misstatement relates to information
supplied by the Company or by the applicable Holder of Registrable Securities
and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such misstatement or alleged misstatement.
The Company and each Holder of Registrable Securities agree that it would not
be just and equitable if contribution pursuant to this Section 2.10(d) were
determined by PRO RATA allocation or by any other method of allocation which
does not take account of the equitable considerations referred to above.
Notwithstanding the provisions of this Section 2.10(d), no Holder shall be
required to contribute any amount in excess of the net proceeds (after
deducting any discounts or commissions received by an underwriter in
connection with such registration) from the offering received by such Holder.
No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the Securities Act) shall be entitled to contribution
hereunder from any person who was not guilty of such fraudulent
misrepresentation.

                  (e) The obligations of the Company and Holders under this
Section 2.10 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Section 2, and otherwise.

                  2.11 REPORTS UNDER SECURITIES EXCHANGE ACT OF 1934. With a
view to making available to the Holders the benefits of Rule 144 promulgated
under the Securities Act and any other rule or regulation of the SEC that may
at any time permit a Holder to sell securities of the Company to the public
without registration or pursuant to a registration on Form S-3, the Company
agrees to:


                                    -10-
<Page>

                  (a) make and keep public information available, as those
terms are understood and defined in SEC Rule 144, at all times after 90 days
after the effective date of the first registration statement filed by the
Company for the offering of its securities to the general public;

                  (b) take such action, including the voluntary registration
of its Common Stock under section 12 of the Exchange Act, as is necessary to
enable the Holders to utilize Form S-3 for the sale of their Registrable
Securities, such action to be taken as soon as practicable after the end of
the fiscal year in which the first registration statement filed by the
Company for the offering of its securities to the general public is declared
effective;

                  (c) file with the SEC in a timely manner all reports and
other documents required of the Company under the Securities Act and the
Exchange Act; and

                  (d) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has compiled with the reporting requirements of SEC Rule 144
(at any time after 90 days after the effective date of the first registration
statement filed by the Company), the Securities Act and the Exchange Act (at
any time after it has become subject to such reporting requirements), or that
it qualifies as a registrant whose securities may be resold pursuant to Form
S-3 (at any time after it so qualifies), (ii) a copy of the most recent
annual or quarterly report of the Company and such other reports and
documents so filed by the Company and (iii) such other information as may be
reasonably requested in availing any Holder of any rule or regulation of the
SEC which permits the selling of any such securities without registration or
pursuant to such form.

                  2.12 FORM S-3 REGISTRATION. In case the Company shall
receive from any Holder or Holders a written request or requests that the
Company effect a registration on Form S-3 and any related qualification or
compliance with respect to all or a part of the Registrable Securities owned
by such Holder or Holders, the Company will:

                  (a) promptly give written notice of the proposed
registration, and any related qualification or compliance, to all other
Holders; and

                  (b) as soon as practicable, effect such registration and
all such qualifications and compliances as may be so requested and as would
permit or facilitate the sale and distribution of all or such portion of such
Holder's or Holders' Registrable Securities as are specified in such request,
together with all or such portion of the Registrable Securities of any other
Holder or Holders joining in such request as are specified in a written
request given within 15 days after receipt of such written notice from the
Company; provided, however, that the Company shall not be obligated to effect
any such registration, qualification or compliance pursuant to this Section
2.12: (i) if Form S-3 is not available for such offering by the Holders; (ii)
if the Holders, together with the holders of any other securities of the
Company entitled to inclusion in such registration, propose to sell
Registrable Securities and such other securities (if any) at an aggregate
price to the public (net of any underwriters' discounts or commissions) of
less than $1,000,000; (iii) if the Company shall furnish to the Holders a
certificate signed by the President of the Company stating that in the good
faith judgment of the Board of Directors of the Company it would be seriously
detrimental to the Company and stockholders for such Form S-3


                                    -11-
<Page>

Registration to be effected at such time, in which event the Company shall
have the right to defer the filing of the Form S-3 Registration Statement for
a period of not more than 90 days after receipt of the request of the Holder
or Holders under this Section 2.12; provided, however, that the Company shall
not utilize this right more than once in any 12-month period; (iv) if the
Company has, within the 12-month period preceding the date of such request,
already effected two registrations on Form S-3 for the Holders pursuant to
this Section 2.12 and other similar provisions granting rights to
registration on Form S-3; (v) if in any particular jurisdiction in which the
Company would be required to qualify to do business or to execute a general
consent to service of process in effecting such registration, qualification
or compliance; or (vi) if the Holders hold in the aggregate less than 1% of
the outstanding shares of the Company's capital stock.

                  (c) Subject to the foregoing, the Company shall file a
registration statement covering the Registrable Securities and other
securities so requested to be registered as soon as practicable after receipt
of the request or requests of the Holders. All expenses incurred in
connection with a registration requested pursuant to Section 2.12, including
(without limitation) all registration, filing, qualification, printer's and
accounting fees and the reasonable fees and disbursements of counsel for the
selling Holder or Holders and counsel for the Company (with the payment of
fees and disbursements of counsel for the Company dependent upon the
Company's including securities in such registration), shall be borne pro rata
by the Holder or Holders participating in the Form S-3 Registration;
provided, however, that the Company shall bear and pay all such expenses,
including (without limitation) all registration, filing and qualification
fees, printer's and accounting fees and the fees and disbursements of one
counsel for the selling Holders, but excluding underwriting discounts and
commission relative to the Registrable Securities, with respect to the first
three such registration pursuant to this Section 2.12. Registrations effected
pursuant to this Section 2.12 shall not be counted as demands for
registration effected pursuant to Section 2.2.

                  2.13 ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause
the Company to register Registrable Securities pursuant to this Section 2 may
be assigned by a Holder to (i) a transferee or assignee of at least 100,000
of such Holder's shares of Registrable Securities, (ii) another Holder, (iii)
in the case of a partnership to a partner or retired partner of such
partnership who after such assignment holds at least 20,000 shares of
Registrable Securities or (iv) an affiliated entity controlling, controlled
by, or under common control with, such Holder; provided, in each case, the
Company is, within a reasonable time after such transfer, furnished with
written notice of the name and address of such transferee or assignee and the
securities with respect to which such registration rights are being assigned;
and provided, further, that such assignment shall be effective only if
immediately following such transfer the further disposition of such
securities by the transferee or assignee is restricted under the Securities
Act.

                  2.14 LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS. From
and after the date of this Agreement, the Company shall not, without the
prior written consent of the Holders of a majority of the outstanding
Registrable Securities, enter into any agreement with any holder or
prospective holder of any securities of the Company which would allow such
holder or prospective holder (a) to include such securities in any
registration filed under Sections 2.2 or 2.3 hereof, unless under the terms
of such agreement, such holder or prospective holder may include


                                    -12-
<Page>

such securities in any such registration only to the extent that the
inclusion of such holder's securities will not reduce the amount of the
Registrable Securities of the Holders which is included or (b) to make a
demand registration which could result in such registration statement being
declared effective prior to the earlier of either of the dates set forth in
subsection 2.2(a) or within 120 days of the effective date of any
registration effected pursuant to Section 2.2.

                  2.15 MARKET STAND-OFF AGREEMENT. Each Holder hereby agrees
that it shall not, to the extent requested by the Company and an underwriter
of Common Stock (or other securities) of the Company, sell or otherwise
transfer or dispose (other than to those donees who agree to be similarly
bound) of any Registrable Securities during a reasonable and customary period
of time, as agreed to by the Company and the underwriters, not to exceed 180
days, following the effective date of a registration statement of the Company
filed under the Securities Act (the "Lock-Up Period"); provided, however,
that:

                  (a) such agreement shall be applicable only to the first
such registration statement of the Company which covers shares (or
securities) to be sold on its behalf to the public in an underwritten
offering; and

                  (b) all officers and directors of the Company, all holders
of at least one percent (1%) of the issued and outstanding securities of the
Company and all other persons with registration rights (whether or not
pursuant to this Agreement) enter into similar agreements.

                  In order to enforce the foregoing covenant, the Company may
impose stop-transfer instructions with respect to the Registrable Securities
of each Holder (and the shares or securities of every other person subject to
the foregoing restriction) until the end of such reasonable and customary
period.

                  Neither the Company nor the underwriters in a public
offering shall reduce or eliminate the Lock-Up Period for any security holder
of the Company without similarly reducing or eliminating the Lock-Up Period
for each Holder.

                  2.16 TERMINATION OF REGISTRATION RIGHTS. The Company's
obligations pursuant to this Section 2 shall terminate as to any Holder of
Registrable Securities on the earlier of (i) when the Holder can sell all of
such Holder's shares pursuant to Rule 144 under the Securities Act during any
90-day period or (ii) on the seventh anniversary of any Closing of the
Company's sale of its Common Stock in a bona fide, firm commitment
underwritten public offering registered under the Securities Act which
results in gross offering proceeds of at least $15,000,000, at a public
offering price of not less than $7.50 per share (adjusted to reflect stock
dividends, stock splits or recapitalizations); provided, however, in no event
shall such obligations terminate earlier than the first anniversary of any
Closing of the offering described in subsection (ii) of this Section 2.17.

3.       COVENANTS.

                  3.1 DELIVERY OF FINANCIAL STATEMENTS. The Company shall
deliver to each Investor and assignee holding that certain number of shares
of Series A Preferred Stock, Series B


                                    -13-
<Page>

Preferred Stock, Series C Preferred Stock or Series D Preferred Stock,
adjusted for stock splits, reverse stock splits and similar changes in
capitalization (the "Preferred Shares") as designated below and any such
Investor or assignee may redistribute to any other Investor or assignee the
information specified in paragraphs (a) through (f) below:

                  (a) to holders of at least 100,000 Preferred Shares, as
soon as practicable, but in any event within 90 days after the end of each
fiscal year of the Company, a statement of operations for such fiscal year, a
balance sheet of the Company as of the end of such year, and a statement of
cash flows for such year, such year-end financial reports to be in reasonable
detail, prepared in accordance with generally accepted accounting principles
("GAAP"), and audited and certified by independent public accountants of
nationally recognized standing selected by the Company;

                  (b) to holders of at least 100,000 Preferred Shares, within
30 days of the end of each calendar quarter, an unaudited statement of
operations, statement of cash flows and balance sheet for and as of the end
of such quarter, in reasonable detail; such quarterly statements shall also
contain the foregoing information on a year-to-date basis and shall also
compare actual performance to budget;

                  (c) to holders of at least 500,000 Preferred Shares, within
30 days of the end of each month, an unaudited statement of operations,
statement of cash flows and balance sheet for and as of the end of such
month, in reasonable detail; such monthly statements shall also contain the
foregoing information on a year-to-date basis and shall also compare actual
performance to budget;

                  (d) to holders of at least 100,000 Preferred Shares, not
less than 30 days prior to the close of each fiscal year, a comprehensive
operating budget for the next fiscal year forecasting the Company's revenues,
expenses and cash positions, prepare on a monthly basis, including balance
sheets and sources and applications of funds statements for such months and,
as soon as prepared, any other budgets or revised budgets prepared by the
Company;

                  (e) to holders of at least 100,000 Preferred Shares, such
other information relating to the financial condition, business, prospects or
corporate affairs of the Company as Investor may from time to time request,
provided, however, that the Company shall not be obligated to provide
information which it deems in good faith to be proprietary; and

                  (f) with respect to the financial statements called for in
subsection (a) of this Section 3.1, an instrument executed by the Chief
Financial Officer or the President of the Company and certifying that such
financials were prepared in accordance with internally consistent accounting
methods consistently applied with prior practice for earlier periods and
fairly present the financial condition of the Company and its results of
operation for the period specified, subject to year-end audit adjustment.

                  3.2 INSPECTION. The Company shall permit each Investor, at
such Investor's expense and with reasonable prior notice, to visit and
inspect the Company's properties, to examine its books of account and records
and to discuss the Company's affairs, finances and


                                     -14-
<Page>

accounts with its officers, all at such reasonable times as may be requested
by Investor; provided, however, that the Company shall not be obligated
pursuant to this Section 3.2 to provide access to any information which it
reasonably considers to be a trade secret or similar confidential information.

                  3.3 TERMINATION OF COVENANTS. The covenants set forth in
Sections 3.1 and 3.2 hereof shall terminate and be of no further force or
effect when the sale of securities pursuant to a registration statement filed
by the Company under the Securities Act in connection with the firm
commitment underwritten offering of its securities to the general public is
consummated or when the Company first becomes subject to the periodic
reporting requirements of section 13(a) or 15(d) of the Exchange Act,
whichever event shall first occur; provided that the Company shall furnish,
for five years following the termination of such covenants, to Investor
copies of its reports on Forms 10-K and 10-Q within 10 days after filing with
the SEC.

                  3.4 PROPRIETARY INFORMATION AGREEMENTS. The Company shall
use its best efforts to cause that all employees of and consultants to the
Company having access to the Company's proprietary and confidential
information shall execute proprietary information agreements with the Company
approved by the Company's Board of Directors.

                  3.5 OPTION VESTING. All options or warrants hereafter
granted by the Company to its employees, officers, directors, consultants or
advisors ("Restricted Parties"), all Options previously granted by the
Company's Board of Directors but not yet evidenced by an Option grant, and
all restricted stock purchase agreements hereafter entered into by the
Company with Restricted Parties, will be subject to a vesting schedule
providing for twenty-five percent (25%) vesting after the first twelve (12)
months of employment and daily vesting as to the remaining seventy-five
percent (75%) of the shares over the following thirty six (36) months after
the first anniversary of the employment commencement date, or such other
vesting schedule as is approved by the Company's Compensation Committee.

                  3.6 COMPLIANCE WITH LAW. (i) The operations of the Company
and its Subsidiaries will be conducted in compliance with all Applicable Laws
promulgated by any Governmental Authority, including, without limitation, all
Applicable Laws relating to consumer protection, equal opportunity, health,
health care industry regulation, third party reimbursement (including
Medicare, Medicaid, and workers compensation), environmental protection,
fire, zoning and building and occupational safety matters, except for
noncompliance that individually or in the aggregate would not and, insofar as
may reasonably be foreseen, in the future will not, have a material adverse
effect on the Company or any Subsidiary.

                  (ii) In addition to and without limiting the generality of
the foregoing, the Company shall adopt and implement a compliance plan
adequate to assure such compliance. The compliance plan shall include all
material elements of an effective program to prevent and detect violations of
law as identified in Commentary 3(k) to Section 8A1.2 of the federal
Sentencing Guidelines.

                  (iii) DEFINITIONS.  For purposed of this Section 3.6:


                                     -15-
<Page>

                  "Applicable Law" means, with respect to any person or
entity, any federal, state or local statute, law, ordinance, rule,
administrative interpretation, regulation, order, writ, injunction,
directive, judgment, decree or other requirement of any governmental
authority applicable to such person or entity or any of its Subsidiaries or
any of their respective properties, assets, officers, directors, employees,
consultants or agents.

                  "Governmental Authority" means any branch, component,
agency or instrumentality of federal, state or local government.

                  "Subsidiary" means any entity which is wholly-owned by the
Company or in which the Company has a beneficial ownership interest,
including any partnership or joint venture entity.

                  3.7 INSURANCE. The Company and each of the Subsidiaries
will maintain in full force and effect with insurers insurance in such
amounts and against such losses and risks as is sufficient and reasonable
given the nature of their respective businesses.

4.       SALES BY INVESTORS.

                  4.1 RIGHT OF FIRST REFUSAL. The parties agree that before
there can be a valid sale, assignment or transfer by any Investor of 20,000
shares or more of the Company's Series A Preferred Stock, Series B Preferred
Stock, Series C Preferred Stock, Series D Preferred Stock, Series E Preferred
Stock or Series F Preferred Stock within any six (6) month period (other than
(i) a transfer not involving a change in beneficial ownership, (ii)
transactions involving the distribution of such shares by any of the
Investors to any of their partners, or stockholders, (iii) pursuant to a
transfer without consideration to the spouse or lineal descendants of the
transferring Investor, or a trust for the benefit of the transferring
Investor, his spouse and/or lineal descendants or (iv) a transfer to an
affiliated entity controlling, controlled by, or under common control with,
the Investor), the Investor intending to transfer (the "Selling Investor")
shall first give notice in writing (the "Notice of Sale") to the Company of
his, her or its intention to sell such shares (the "Noticed Shares"). Such
Notice of Sale shall specify the number of Notice Shares to be sold, the name
of the proposed purchaser (the "Proposed Investor Purchaser"), the price per
Noticed Share and the terms and conditions upon which the Selling Investor
intends to make such sale. Promptly upon the Company's receipt of such Notice
of Sale, the Secretary of the Company shall mail or deliver a copy of such
Notice of Sale to all Investors owning an aggregate of Common Stock
Equivalents (as hereafter defined) representing at least 100,000 shares of
Common Stock (as adjusted for stock splits, contributions and stock
dividends) (such stockholders being hereinafter referred to as the "Optionee
Investors"). Within thirty (30) days thereafter, any such Optionee Investor
or Investor (the "Offering Investor") desiring to acquire any part or all of
the Noticed Shares shall deliver by mail or otherwise to the Secretary of the
Company a written offer or offers, to purchase a specified number of such
Noticed Shares at the price and upon the terms and conditions stated in such
Notice of Sale, accompanied by the stated consideration therefor with
authorization to transfer such consideration against delivery of such shares,
which offers, subject to Section 4.2, shall be accepted by the Selling
Investor. As used herein, "Common Stock Equivalents" shall mean outstanding
shares of Common Stock and shares of Common Stock issuable upon conversion of


                                      -16-
<Page>

outstanding Series A Preferred Stock, Series B Preferred Stock, Series C
Preferred Stock, Series D Preferred Stock, Series E Preferred Stock or Series
F Preferred Stock.

                  If the total number of shares specified in said offers to
the Secretary exceeds the number of the Noticed Shares, each Offering
Investor shall be entitled to purchase that number of shares which is equal
to the lesser of:

                  (i) the number of shares specified in said offer or,

                  (ii) such proportion of the Notice Shares as the number of
shares (on an as-if-converted basis) that such Offering Investor holds bears
to the total number of shares held by all the Offering Investors (on an
as-if-converted basis).

                  If all of the Noticed Shares are not disposed of under the
apportionment pursuant to this Section 4.1, those shares remaining undisposed
of shall be apportioned among those Offering Investors whose number of Shares
specified in their respective offers under Section 4.1 exceed the number of
shares allocated to them, which excess shares shall be apportioned on the
basis of the apportionment formula set forth in this Section, and said
apportionment process shall be repeated with respect to any excess shares
after each apportionment until all Noticed Shares are allocated.

                  4.2 FAILURE TO EXERCISE OPTIONS AND MAKE OFFERS FOR ALL
SHARES. If options are not exercised and/or offers made in the aggregate for
all of the Noticed Shares within the thirty (30) day period referred to
herein, the Selling Investors shall not be obligated to sell the Noticed
Shares or any fraction thereof to the Optionee Investors, and may dispose of
all of the Noticed Shares to the Proposed Purchaser named in said Notice of
Sale, provided, however, that the Selling Investor shall not sell less than
all of said Noticed Shares nor shall it sell such shares at a lower price or
on terms or conditions more favorable to the Proposed Purchaser than those
specified in said Notice of Sale without first offering the new price, terms
and conditions to Optionee Investors as hereinabove set forth. If the Selling
Investor does not so sell the Noticed Shares to such Proposed Purchaser
within one hundred twenty (120) days after it first gave notice to the
Company pursuant to Section 4.1, it shall again first offer such shares to
the Optionee Investors prior to selling them to any Proposed Purchaser.

                  4.3 NONMONETARY CONSIDERATION.

                  (a) If part or all of the purchase consideration specified
in a Notice of Sale is other than money or purchaser's promissory note or
other evidence of indebtedness, such Notice of Sale shall also specify the
fair market value in cash of such other consideration. The Optionee Investors
shall have the right to exercise their respective options to purchase the
Noticed Shares by delivery of a written offer or offers specifying a cash
purchase price equal to the total of the monetary consideration and the fair
market value of the nonmonetary consideration specified in the Notice of Sale.

                  (b) If any Optionee Investor objects to the amount
specified in the Notice of Sale as the fair market value of any nonmonetary
consideration, such Optionee Investor shall,


                                     -17-
<Page>

within twenty (20) days of the receipt of the Notice of Sale, submit a
written request to the Company that the matter be submitted to the Board of
Directors for determination. Pending such determination, or a determination
pursuant to subsection (c) below, the time for exercising options to purchase
shares shall be stayed as of the date of such notice. Promptly upon the
Company's receipt of such notice from the objecting Optionee Investor, the
Secretary of the Company shall notice and call a special meeting of the Board
of Directors, to be held within fifteen (15) days of the Company's receipt of
notice from the objecting Optionee Investor, for the purpose of determining
in good faith the fair market value of the nonmonetary consideration
specified in the Notice of Sale. Any decision of the Board of Directors made
in good faith shall be final and binding upon all parties. The Board of
Directors shall promptly give written notice of its decision and the
resulting calculation of the purchase price to the parties.

                  (c) If the Board of Directors fails or refuses to make a
determination of the fair market value of such nonmonetary consideration within
such fifteen (15) day period from the date of the Company's receipt of notice
from the objecting Optionee Investor, the objecting Optionee Investor and the
Selling Investor shall select and agree upon a single appraiser. If the parties
are unable to agree upon a single appraiser within ten (10) days after the end
of the fifteen (15) day period specified above, then either party may apply to
the San Diego Superior Court (pursuant to a petition to compel arbitration) for
the appointment of a single appraiser in accordance with Section 1280 ET SEQ. of
the California Code of Civil Procedure. Such appraiser shall thereupon promptly
determine the fair market value of the nonmonetary consideration specified in
the Notice of Sale, and shall promptly give written notice of such appraiser's
decision and the resulting calculation of the purchase price to the parties and
to the Company.

                  (d) All expenses of the determination by the Board of
Directors or the appraisal and proceedings to appoint an appraiser, as the case
may be, shall be borne one-half by the Optionee Investors who exercise their
options to purchase the Noticed Shares (who shall share such expenses among
themselves in proportion to the number of shares each elects to purchase) and
one-half by the Selling Investor, unless the Optionee Investors thereafter fail
to exercise their respective options, in which case the objecting Optionee
Investor shall bear all such expenses.

                  4.4 TERMINATION. Notwithstanding the foregoing, the rights of
first refusal set forth in this Section 4 shall terminate upon any Closing of
the Company's first firmly underwritten public offering of its Common Stock
registered under the Securities Act of 1933.

5.       MISCELLANEOUS.

                  5.1 SUCCESSORS AND ASSIGNS. Except as otherwise provided
herein, the terms and conditions of this Agreement shall inure to the benefit of
and be binding upon the respective successors and assigns of the parties
(including transferees of any shares of Registrable Securities). Nothing in this
Agreement, express or implied, is intended to confer upon any party other than
the parties hereto or their respective successors and assigns any rights,
remedies, obligations, or liabilities under or by reason of this Agreement,
except as expressly provided in this Agreement.


                                     -18-
<Page>
                  5.2 GOVERNING LAW; JURY TRIAL WAIVER. This Agreement shall be
governed by and construed under the laws of the State of California as applied
to agreements among California residents entered into and to be performed
entirely within California. THE PARTIES HERETO IRREVOCABLY WAIVE ALL RIGHTS TO A
TRIAL BY JURY IN ANY SUIT, ACTION OR OTHER PROCEEDING INSTITUTED BY OR AGAINST
THE PARTY IN RESPECT OF ITS OBLIGATIONS HEREUNDER OR THE TRANSACTIONS
CONTEMPLATED HEREBY.

                  5.3 COUNTERPARTS. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                  5.4 TITLES AND SUBTITLES. The titles and subtitles used in
this Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

                  5.5 NOTICES. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon personal delivery to the party to be notified or upon
deposit with the United States Post Office, by registered or certified mail,
postage prepaid, and telecopier, and addressed to the party to be notified at
the address indicated for such party on the signature page hereof, or at such
other address as such party may designate by ten (10) days' advance written
notice to the other parties.

                  5.6 EXPENSES. If any action at law or in equity is necessary
to enforce or interpret the terms of this Agreement, the prevailing party shall
be entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

                  5.7 AMENDMENTS AND WAIVERS. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the holders of
a majority of the Registrable Securities then outstanding; provided, however,
that any such amendment or waiver which would have a disproportionate effect on
any Holder shall require the written consent of such Holder. Any amendment or
waiver effected in accordance with this paragraph shall be binding upon each
holder of any Registrable Securities then outstanding, each future holder of all
such Registrable Securities, and the Company.

                  5.8 SEVERABILITY. If one or more provisions of this Agreement
are held to be unenforceable under applicable law, such provision shall be
excluded from this Agreement and the balance of the Agreement shall be
interpreted as if such provision were so excluded and shall be enforceable in
accordance with its terms.

                  5.9 AGGREGATION OF STOCK. All shares of Registrable Securities
held or acquired by affiliated entities or persons shall be aggregated together
for the purpose of determining the availability of any rights under this
Agreement.


                                     -19-
<Page>

                  5.10 ENTIRE AGREEMENT. This Agreement, a letter agreement
between the Company and GE Capital Equity Investments, Inc. dated of even date
herewith, a letter agreement between the Company and Merrill Lynch Ventures L.P.
2001 dated of even date herewith and the documents referred to herein constitute
the entire agreement among the parties hereto and no party shall be liable or
bound to any other party in any manner by any warranties, representations, or
covenants except as specifically set forth herein or therein.


              [THE REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]












                                     -20-
<Page>



         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

COMPANY:                           DIGIRAD CORPORATION,
                                   a Delaware corporation

                                   By:      /s/ Scott Huennekens
                                      -----------------------------------------
                                            Scott Huennekens, President

FOUNDERS:                          JACK F. BUTLER

                                   By:      /s/ Jack F. Butler
                                      -----------------------------------------
                                               Jack F. Butler

                     Address:      16650 Las Cuestas
                                   Rancho Santa Fe, CA  92067


                                   CLINTON L. LINGREN


                                   By:     /s/ Clinton L. Lingren
                                      -----------------------------------------
                                              Clinton L. Lingren

                     Address:      6211 Hannon Ct.
                                   San Diego, CA  92117











                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                                INVESTORS' RIGHTS AGREEMENT]

<Page>




EXISTING INVESTORS:

                                   KINGSBURY CAPITAL PARTNERS, L.P.

                                   By:      Kingsbury Associates, L.P.,
                                            Its General Partner


                                   By:    /s/ Timothy J. Wollaeger
                                      -----------------------------------------
                                            Timothy J. Wollaeger,
                                            General Partner

                                   KINGSBURY CAPITAL PARTNERS, L.P., II

                                   By:      Kingsbury Associates, L.P.,
                                            Its General Partner


                                   By:     /s/ Timothy J. Wollaeger
                                      -----------------------------------------
                                            Timothy J. Wollaeger,
                                            General Partner

                                   KINGSBURY CAPITAL PARTNERS, L.P., III

                                   By:      Kingsbury Associates, L.P.,
                                            Its General Partner


                                   By:     /s/ Timothy J. Wollaeger
                                      -----------------------------------------
                                            Timothy J. Wollaeger,
                                            General Partner

                                   KINGSBURY CAPITAL PARTNERS, L.P., IV


                                   By:      Kingsbury Associates, L.P.,
                                            Its General Partner


                                   By:     /s/ Timothy J. Wollaeger
                                      -----------------------------------------
                                            Timothy J. Wollaeger,
                                            General Partner

                  Address:         3655 Nobel Drive, Suite 490
                                   San Diego, CA  92122




                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                                INVESTORS' RIGHTS AGREEMENT]

<Page>



EXISTING INVESTORS:

                                   SORRENTO GROWTH PARTNERS I, L.P.


                                   By:      Sorrento Equity Growth Partners
                                            I, L.P., Its General Partner

                                   By:      Sorrento Associates, Inc.,
                                            Its General Partner


                                   By:     /s/ Robert M. Jaffee
                                      -----------------------------------------
                                            Robert M. Jaffe, President



                                   SORRENTO VENTURES II, L.P.


                                   By:      Sorrento Equity Partners, L.P.,
                                            Its General Partner

                                   By:      Sorrento Associates, Inc.,
                                            Its General Partner


                                   By:     /s/ Robert M. Jaffe
                                      -----------------------------------------
                                            Robert M. Jaffe, President


                  Address:         4370 La Jolla Village Drive, Suite 1040
                                   San Diego, CA  92122




                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                                INVESTORS' RIGHTS AGREEMENT]

<Page>



EXISTING INVESTORS:

                       SORRENTO VENTURES III, L.P.


                       By:    /s/ Robert M. Jaffe
                          -----------------------------------------
                            Robert M. Jaffe
                            President, Sorrento Associates, Inc.
                            General Partner, Sorrento Equity Partners III, L.P.
                            General Partner, Sorrento Ventures III, L.P.


                       SORRENTO VENTURES CE, L.P.

                       By:    /s/ Robert M. Jaffe
                          -----------------------------------------
                            Robert M. Jaffe
                            President, Sorrento Associates, Inc.
                            General Partner, Sorrento Equity Partners III, L.P.
                            General Partner, Sorrento Ventures CE, L.P.



               Address:     4370 La Jolla Village Drive, Suite 1040
                            San Diego, CA  92122





                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                                INVESTORS' RIGHTS AGREEMENT]

<Page>



EXISTING INVESTORS:

                                  VECTOR LATER-STAGE EQUITY FUND, L.P.

                                  By:      Vector Fund Management II, L.L.C.
                                           Its General Partner


                                  By:     /s/ Doug Reed
                                     -----------------------------------------
                                           Doug Reed
                                           Managing Director

                                 VECTOR LATER-STAGE EQUITY FUND II, L.P.

                                 By:      Vector Fund Management II, L.L.C.
                                          Its General Partner


                                 By:      /s/ Doug Reed
                                     -----------------------------------------
                                           Doug Reed
                                           Managing Director

                                 VECTOR LATER-STAGE EQUITY FUND II (Q.P.), L.P.

                                  By:      Vector Fund Management II, L.L.C.
                                           Its General Partner


                                  By:     /s/ Doug Reed
                                      -----------------------------------------
                                           Doug Reed
                                           Managing Director

                  Address:         1751 Lake Cook Road, Suite 350
                                   Deerfield, IL  60015




                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                               INVESTORS' RIGHTS AGREEMENT]



<Page>



EXISTING INVESTORS:

                                   PALIVACINNI PARTNERS, LP



                                   By:    /s/ Doug Reed
                                      -----------------------------------------
                                           Doug Reed
                                           Managing Director

                  Address:         1751 Lake Cook Road, Suite 350
                                   Deerfield, IL  60015















                           [SIGNATURE PAGE TO AMENDED AND RESTATED
                               INVESTORS' RIGHTS AGREEMENT]

<Page>



EXISTING INVESTORS:


                                   AUREUS DIGIRAD, LLC


                                   By:          /s/ Robert M. Averick
                                      -----------------------------------------

                                   Name:        Robert M. Averick
                                      -----------------------------------------

                                   Its:         Member
                                      -----------------------------------------

                  Address:         100 First Stamford Place
                                   Stamford, CT  06902




<Page>



EXISTING INVESTORS:


                                   MERRILL LYNCH VENTURES, L.P. 2001



                                   By:      Merrill Lynch Ventures LLC
                                            Its General Partner

                                   By:          /s/ Edward J. Higgins
                                      -----------------------------------------
                                            Edward J. Higgins
                                            Vice President

                  Address:         2 World Financial Center, 31st Floor
                                   New York, NY 10281
                                   Attn:  Jean Kim

                   All Notices:    Merrill Lynch Ventures, L.P. 2001
                                   95 Greene Street
                                   Jersey City, NJ 07302-3815
                                   Attn:  Robert F. Tully


<Page>



EXISTING INVESTORS:


                                   INGLEWOOD VENTURES, L.P.



                                   By:          /s/ Daniel C. Wood
                                      -----------------------------------------
                                            Daniel C. Wood
                                   Title:       Member
                                         --------------------------------------

                  Address:         12526 High Bluff Drive, Suite 300
                                   San Diego, CA  92130






<Page>



EXISTING INVESTORS:


                                    ANACAPA INVESTORS, LLC -
                                    ANACAPA I

                                    By:          /s/ Robert Raede
                                       ----------------------------------------
                                             Robert Raede
                                             Manager

                   Address:         32 W. Anapamu Street, #350
                                    Santa Barbara, CA  93101




<Page>



EXISTING INVESTORS:


                                   KENNETH E. OLSON TRUST DATED 3/16/89



                                   By:          K. Olson
                                      -----------------------------------------

                                   Name:        Trustee
                                        ---------------------------------------

                                  Title:
                                        ---------------------------------------

                 Address:         404 Torrey Point Road
                                  Del Mar, CA  92014


<Page>



EXISTING INVESTORS:


                                     MID-CAROLINA CARDIOLOGY, PA

                                     By:      /s/ Stephen A. McAdams
                                        ---------------------------------------
                                              Stephen A. McAdams, M.D.
                                              Chief Executive Officer

                     Address:        1718 East Fourth Street, Suite 501
                                     Charlotte, NC  28204



                                     STEPHEN A. MCADAMS AND LOU ANN MCADAMS

                                              /s/ Stephen A. McAdams
                                     ------------------------------------------
                                     Stephen A. McAdams


                                              /s/ Lou A. McAdams
                                     ------------------------------------------
                                     Lou Ann McAdams


                     Address:        1718 East Fourth Street, Suite 501
                                     Charlotte, NC  28204



<Page>





NEW INVESTORS:

                                    SILICON VALLEY BANK

                                    By:               /s/ Patrick J. O'Donnell
                                       ----------------------------------------

                                    Name:             Patrick J. O'Donnell
                                         --------------------------------------

                                    Title:            Regional Market Manager
                                          -------------------------------------

                                    Dated as of the Date of the Agreement

                    Address:        3003 Tasman Drive, HG 110
                                    Santa Clara, CA  95054
                                    Attention:  Treasury Department


<Page>



NEW INVESTORS:


                                    D. THEODORE BERGHORST


                                    /s/ D. Theodore Berghorst
                                    -------------------------------------------
                                    Signature

                    Address:        12 Kent Road
                                    Winnetka, IL 60093


                                    BERGHORST 1998 DYNASTIC TRUST


                         By:               /s/ D. Theodore Berghorst
                                    -------------------------------------------
                                    D. Theodore Berghorst as Financial Advisor

                    Address:        12 Kent Road
                                    Winnetka, IL  60093



<Page>



NEW INVESTORS:


                                    PETER F. DRAKE

                                             /s/ Peter F. Drake
                                    -----------------------------------------
                                    Signature

                    Address:        255 Mayflower Road
                                    Lake Forest, IL 60045

<Page>

NEW INVESTORS:

                                   IMPERIAL VENTURES, INC.

                                   By:       /s/ James Rutter
                                        ---------------------------------------
                                        James B. Rutter
                                        President

                      Address:     11512 El Camino Real, Suite 350
                                   San Diego, CA  92130


<Page>

NEW INVESTORS:

                                    STEPHEN A. MCADAMS ROLLOVER IRA

                                    By:         /s/ Stephen A. McAdams
                                          -------------------------------------
                                          Stephen A. McAdams

                       Address:     1718 East Fourth Street, Suite 501
                                    Charlotte, NC  28204



<Page>

NEW INVESTORS:

                                    W AUGUST HILLENBRAND

                                          /s/ W. August Hillenbrand
                                    ------------------------------------------
                                    Signature

                        Address:    700 S.R. 46E
                                    Batesville, IN  47006



<Page>

NEW INVESTORS:

                                    TAH & H INVESTORS, LP

                                    By:      Investment Committee
                                             Brickyard Holdings. Inc.
                                             Its General Partner


                                    By:            /s/ Charles W. Crowther
                                             ----------------------------------
                                             Charles W. Crowther
                                             Investment Committee Member


                                    KKH & C INVESTORS, LP

                                    By:      Investment Committee
                                             Brickyard Holdings. Inc.
                                             Its General Partner


                                    By:             /s/ Charles W. Crowther
                                             ----------------------------------
                                             Charles W. Crowther
                                             Investment Committee Member


                                    WAH & M INVESTORS, LP

                                    By:      Investment Committee
                                             Brickyard Holdings. Inc.
                                             Its General Partner


                                    By:            /s/ Charles W. Crowther
                                             ----------------------------------
                                             Charles W. Crowther
                                             Investment Committee Member


                    Address:        5 Observatory Hill
                                    Cincinnati, OH  45208



<Page>

NEW INVESTORS:

                                    MLH & T INVESTORS, LP

                                    By:      Investment Committee
                                             Brickyard Holdings. Inc.
                                             Its General Partner


                                    By:            /s/  Charles W. Crowther
                                             ----------------------------------
                                             Charles W. Crowther
                                             Investment Committee Member


                                    RDH & S INVESTORS, LP

                                    By:      Investment Committee
                                             Brickyard Holdings. Inc.
                                             Its General Partner


                                    By:            /s/ Charles W. Crowther
                                             ----------------------------------
                                             Charles W. Crowther
                                             Investment Committee Member


                    Address:        5 Observatory Hill
                                    Cincinnati, OH  45208


<Page>

NEW INVESTORS:

                                   GE CAPITAL EQUITY INVESTMENTS, INC.


                                   By:      /s/ David Gibbs
                                         --------------------------------------
                                         David Gibbs
                                         Senior Vice President

                  Address:         120 Long Ridge Road
                                   Stamford, CT  06927


<Page>


                                   SCHEDULE A

FOUNDERS

Jack Butler, Sr.
Jack Butler, Jr.
Alice Butler
Michael Butler
Patricia Butler
Clinton Lingren
Leslie Lingren
David Lingren
Corinne Avayo
Wallace Goodson
LaVerne Clark
Marcia McChesney
Vera Williams
Marilyn Sargent
Grant Heileson
Carma Farley
Darlene Logan
Kathleen Ipsen
Terry Tervort
Michelle Belnap
Alison Komm

EXISTING INVESTORS

Vector Later-Stage Equity Fund, L.P.
Vector Later-Stage Equity Fund II, L.P.
Vector Later-Stage Equity Fund II (Q.P.), L.P.
Furman Selz SBIC L.P.
Sorrento Growth Partners I, L.P.
Sorrento Ventures II, L.P.
Sorrento Ventures III, L.P.
Sorrento Ventures CE, L.P.
Kingsbury Capital Partners, L.P.
Kingsbury Capital Partners, L.P., II
Kingsbury Capital Partners, L.P., III
Kingsbury Capital Partners L.P., IV
Jack F. Butler, Sr.
Gerald G. Loehr Trust
William L. Ashburn
Karen A. Klause
Kenneth E. Olson Trust
Peter T. Dunn


                                      SCHEDULE A-1

<Page>

Dunn Family Trust
Nathan P. Dunn
Kyla E. Dunn
The Arthur & Sophie Brody Revocable Trust DTD 04/13/89
Malin Burnham
Philip L. Elkus Trust DTD 09/09/74
Elliot Feuerstein Trust DTD 05/14/82
Stanley and Maxine Firestone Trust DTD 12/02/88
Ira R. and Joan P. Katz Qualified Marital Trust
Knowles Family Trust
The SDL Trust
Arthur E. Nicholas
The Stanley E. and Pauline M. Foster Trust DTD  07/31/81
Page Trust DTD 03/03/89
Forrest N. Shumway & Patricia K. Shumway Trust DTD 04/26/94
Derbes Family Trust U/D/T 04/25/86
Sutro Investment Partners V., LLC
SBSF Biotechnology Fund, L.P.
SBSF Biotechnology Partners Fund, L.P.
ABS Employees' Venture Fund Limited Partnership
JAFCO Co., Ltd.
JAFCO R-3 Investment Enterprise Partnership
JAFCO JS3 Investment Enterprise Partnership
JAFCO G-6 (A) Investment Enterprise Partnership
JAFCO G-6 (B) Investment Enterprise Partnership
JAFCO G-7 (A) Investment Enterprise Partnership
JAFCO G-7 (B) Investment Enterprise Partnership
Johnson & Johnson Development Corporation
Health Care Indemnity, Inc.
Mitsui & Co., Ltd.
MVC Global Japan Fund I
Ocean Avenue Investors, LLC - Founders Fund
Ocean Avenue Investors, LLC - Redstone Fund
Aureus Digirad, LLC
Merrill Lynch Ventures, L.P. 2001
Mid-Carolina Cardiology, PA
Stephen A. McAdams and Lou Ann McAdams, as Joint Tenants
Akinyele Aluko, M.D.
Harvey Family LLC
GFP Digirad
Dr. Jerome Williams, Jr.
Dwayne A. Schmidt
Richard N. and Judy F. Linder
Fisk Ventures LLC
IngleWood Ventures, L.P.
The University of North Carolina at Chapel Hill
         Foundation Investment Fund, Inc.
Palivaccini Partners, LP


                                      SCHEDULE A-2

<Page>

Anacapa Investors, LLC -Anacapa I

NEW INVESTORS

GE Capital Equity Investments, Inc.
D. Theodore Berghorst
Imperial Ventures, Inc.
W August Hillenbrand
TAH & H Investors, LP
KKH & C Investors, LP
WAH & M Investors, LP
MLH & T Investors, LP
RDH & S Investors, LP
Peter F. Drake
Silicon Valley Bank
Stephen A. McAdams Rollover IRA


                                      SCHEDULE A-3