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                                                                     EXHIBIT 4.4

                          REGISTRATION RIGHTS AGREEMENT

         This Registration Rights Agreement (this "AGREEMENT") is made and
entered into as of August 28, 2001, among Hyseq, Inc., a Nevada corporation (the
"COMPANY"), and the investors signatory hereto (each a "PURCHASER" and
collectively, the "PURCHASERS").

         This Agreement is made pursuant to the Securities Purchase Agreement,
dated as of the date hereof among the Company and the Purchasers (the "PURCHASE
AGREEMENT").

         The Company and the Purchasers hereby agree as follows:

         1. Definitions. Capitalized terms used and not otherwise defined herein
that are defined in the Purchase Agreement shall have the meanings given such
terms in the Purchase Agreement. As used in this Agreement, the following terms
shall have the following meanings:

         "EFFECTIVENESS DATE" means the 120th day following the Closing Date.

         "EFFECTIVENESS PERIOD" shall have the meaning set forth in Section
2(a).

         "FILING DATE" means the 30th day following the Closing Date.

         "HOLDER" or "HOLDERS" means the holder or holders, as the case may be,
from time to time of Registrable Securities.

         "INDEMNIFIED PARTY" shall have the meaning set forth in Section 5(c).

         "INDEMNIFYING PARTY" shall have the meaning set forth in Section 5(c).

         "LOSSES" shall have the meaning set forth in Section 5(a).

         "MATERIALLY DETRIMENTAL" means, in the good faith judgment of the Board
of Directors of the Company as set forth in a certificate signed by the
President, Chief Financial Officer or General Counsel of the Company, the filing
in question would be materially detrimental to the Company by reason of (i) any
Proceeding before, or material event involving, the Food and Drug
Administration, or (ii) any proposal or plan of the Company or any of its
Subsidiaries to engage in any sale, acquisition, merger, consolidation,
reorganization, tender offer or similar transaction.

         "PROCEEDING" means an action, claim, suit, investigation or proceeding
(including, without limitation, an investigation or partial proceeding, such as
a deposition), whether commenced or threatened.

         "PROSPECTUS" means the prospectus included in a Registration Statement
(including, without limitation, a prospectus that includes any information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 430A


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promulgated under the Securities Act), as amended or supplemented by any
prospectus supplement, with respect to the terms of the offering of any portion
of the Registrable Securities covered by the Registration Statement, and all
other amendments and supplements to the Prospectus, including post-effective
amendments, and all material incorporated by reference or deemed to be
incorporated by reference in such Prospectus.

         "REGISTRABLE SECURITIES" means the Shares and Warrants Shares.

         "REGISTRATION STATEMENT" means the registration statement required to
be filed hereunder including the Prospectus, amendments and supplements to such
registration statement or Prospectus, including pre- and post-effective
amendments, all exhibits thereto, and all material incorporated by reference or
deemed to be incorporated by reference in such registration statement.

         "RULE 144" means Rule 144 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same purpose and effect as such Rule.

         "RULE 415" means Rule 415 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same purpose and effect as such Rule.

         "RULE 424" means Rule 424 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same purpose and effect as such Rule.

         "SPECIAL COUNSEL" means Purchaser Counsel who will be reimbursed by the
Company pursuant to Section 4.

         2. Registration

              (a) On or prior to the Filing Date, the Company shall prepare and
file with the Commission a Registration Statement covering the resale of all
Registrable Securities for an offering to be made on a continuous basis pursuant
to Rule 415. The Registration Statement shall be on Form S-3 (except if the
Company is not then eligible to register for resale the Registrable Securities
on Form S-3, in which case such registration shall be on another appropriate
form in accordance herewith) and shall contain (except if otherwise directed by
the Holders) the "PLAN OF DISTRIBUTION" attached hereto as Annex A. The Company
shall cause such Registration Statement to become effective and remain effective
as provided herein. The Company shall use its best efforts to cause the
Registration Statement to be declared effective under the Securities Act as
promptly as possible after the filing thereof, but in any event prior to its
Effectiveness Date, and shall use its best efforts to keep the Registration
Statement continuously effective under the Securities Act until the date which
is two years after the date that such Registration Statement is declared
effective by the Commission or such earlier date when all Registrable Securities
covered by such Registration Statement have been sold or may be



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sold without volume restrictions pursuant to Rule 144(k) as determined by the
counsel to the Company pursuant to a written opinion letter to such effect,
addressed and acceptable to the Company's transfer agent and the affected
Holders (the "EFFECTIVENESS PERIOD"), provided, that the Company shall not be
deemed to have used its best efforts to keep the Registration Statement
effective during the Effectiveness Period if it voluntarily takes any action
that would result in the Holders not being able to sell the Registrable
Securities covered by such Registration Statement during the Effectiveness
Period, unless such action is required under applicable law or the Company has
filed a post-effective amendment to the Registration Statement and the
Commission has not declared it effective.

              (b) If: (a) any Registration Statement is not filed on or prior to
the Filing Date (if the Company files such Registration Statement without
affording the Holder the opportunity to review and comment on the same as
required by Section 3(a) hereof, the Company shall not be deemed to have
satisfied this clause (a)), or (b) the Company fails to file with the Commission
a request for acceleration in accordance with Rule 461 promulgated under the
Securities Act, within five days of the date that the Company is notified
(orally or in writing, whichever is earlier) by the Commission that a
Registration Statement will not be "reviewed," or not subject to further review,
or (c) a Registration Statement filed hereunder is not declared effective by the
Commission on or prior to its Effectiveness Date, or (d) after a Registration
Statement is filed with and declared effective by the Commission, such
Registration Statement ceases to be effective as to all Registrable Securities
to which it is required to relate at any time prior to the expiration of the
Effectiveness Period without being succeeded within ten Trading Days, or if it
would be Materially Detrimental, Twenty Trading Days, by an amendment to such
Registration Statement or by a subsequent Registration Statement filed with and
declared effective by the Commission, (e) an amendment to a Registration
Statement is not filed by the Company with the Commission within ten Trading
Days or if it would be Materially Detrimental, Twenty Trading Days, of the
Commission's notifying the Company that such amendment is required in order for
such Registration Statement to be declared effective, (f) the Common Stock is
not listed or quoted, or is suspended from trading, on the Trading Market for a
period of three Trading Days in any 12 month period (which need not be
consecutive Trading Days), or (g) the exercise rights of the Holders pursuant to
the Warrants are suspended for any reason (any such failure or breach being
referred to as an "EVENT," and for purposes of clause (a), (c) or (g) the date
on which such Event occurs, or for purposes of clause (b) the date on which such
five day period is exceeded, or for purposes of clauses (d) and (e) the date on
which the applicable Trading Day-period is exceeded, or for purposes of clause
(f) the date on which such three Trading Day period is exceeded, being referred
to as "EVENT DATE"), then: (x) on each such Event Date the Company shall pay to
each Holder an amount in cash, as liquidated damages and not as a penalty, equal
to 1.0% of the aggregate purchase price paid by such Holder pursuant to the
Purchase Agreement; and (y) if the applicable Event has not have been cured by
the first month anniversary following the Event Date, then on such anniversary
date the Company shall pay to each Holder an amount in cash, as liquidated
damages and not as a penalty, equal to 1.0% of the aggregate purchase price paid
by such Holder pursuant to the Purchase Agreement and on each monthly
anniversary thereafter until the applicable Event is cured, the Company shall
pay to each Holder an amount in cash, as liquidated damages and not as a
penalty, equal to 2.0% of the aggregate purchase price paid by such Holder
pursuant to the Purchase Agreement provided, however, that all periods shall be
tolled during delays directly caused by the action or inaction of any Holder,
and the Company shall have no liability in respect of any such delay. If the


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Company fails to pay any liquidated damages pursuant to this Section in full
within seven days after the date payable, the Company will pay interest thereon
at a rate of 15% per annum (or such lesser maximum amount that is permitted to
be paid by applicable law) to the Holder, accruing daily from the date such
liquidated damages are due until such amounts, plus all such interest thereon,
are paid in full.

         3. Registration Procedures

         In connection with the Company's registration obligations hereunder,
the Company shall:

              (a) Not less than (1) five Trading Days prior to the filing of the
Registration Statement or any related Prospectus, (2) three Trading Days prior
to the filing of any pre-effective or post effective amendment to the
Registration Statement or (3) one Trading Day prior to the filing of any
supplement to the Registration Statement (other than a prospectus supplement the
principal purpose of which is to update the list of selling stock holders), the
Company shall, (i) furnish to the Holders and their Special Counsel copies of
all such documents proposed to be filed (including documents incorporated by
reference and not available on the EDGAR system) which documents will be subject
to the review of such Holders and their Special Counsel, and (ii) cause its
officers and directors, counsel and independent certified public accountants to
respond to such inquiries as shall be necessary, in the reasonable opinion of
respective counsel to conduct a reasonable investigation within the meaning of
the Securities Act. The Company shall not file the Registration Statement or any
such Prospectus or any amendments or supplements thereto to which the Holders of
a majority of the Registrable Securities and their Special Counsel shall
reasonably object in good faith.

              (b) (i) Prepare and file with the Commission such amendments,
including post-effective amendments, to the Registration Statement and the
Prospectus used in connection therewith as may be necessary to keep the
Registration Statement continuously effective as to the applicable Registrable
Securities for the Effectiveness Period and prepare and file with the Commission
such additional Registration Statements in order to register for resale under
the Securities Act all of the Registrable Securities; (ii) cause the related
Prospectus to be amended or supplemented by any required Prospectus supplement,
and as so supplemented or amended to be filed pursuant to Rule 424; (iii)
respond as promptly as reasonably possible, and in any event within ten Trading
days, to any comments received from the Commission with respect to the
Registration Statement or any amendment thereto and, as promptly as reasonably
possible provide the Holders true and complete copies of all correspondence from
and to the Commission relating to the Registration Statement; and (iv) comply in
all material respects with the provisions of the Securities Act and the Exchange
Act with respect to the disposition of all Registrable Securities covered by the
Registration Statement during the applicable period in accordance with the
intended methods of disposition by the Holders thereof set forth in the
Registration Statement as so amended or in such Prospectus as so supplemented.

              (c) Notify the Holders of Registrable Securities to be sold and
their Special Counsel as promptly as reasonably possible (and, in the case of
(i)(A) below, not less than three Trading Days prior to such filing) and (if
requested by any such Person) confirm such notice in writing no later than one
Trading Day following the day (i)(A) when a Prospectus or



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any Prospectus supplement or post-effective amendment to the Registration
Statement is proposed to be filed; (B) when the Commission notifies the Company
whether there will be a "review" of such Registration Statement and whenever the
Commission comments in writing on such Registration Statement (the Company shall
provide true and complete copies thereof and all written responses thereto to
each of the Holders); and (C) with respect to the Registration Statement or any
post-effective amendment, when the same has become effective; (ii) of any
request by the Commission or any other Federal or state governmental authority
for amendments or supplements to the Registration Statement or Prospectus or for
additional information; (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of the Registration Statement covering any or
all of the Registrable Securities or the initiation of any Proceedings for that
purpose; (iv) of the receipt by the Company of any notification with respect to
the suspension of the qualification or exemption from qualification of any of
the Registrable Securities for sale in any jurisdiction, or the initiation or
threatening of any Proceeding for such purpose; and (v) of the occurrence of any
event or passage of time that makes the financial statements included in the
Registration Statement ineligible for inclusion therein or any statement made in
the Registration Statement or Prospectus or any document incorporated or deemed
to be incorporated therein by reference untrue in any material respect or that
requires any post-effective amendment to the Registration Statement or
Prospectus so that, in the case of the Registration Statement or the Prospectus,
as the case may be, it will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading.

              (d) Use its best efforts to avoid the issuance of, or, if issued,
obtain the withdrawal of (i) any order suspending the effectiveness of the
Registration Statement, or (ii) any suspension of the qualification (or
exemption from qualification) of any of the Registrable Securities for sale in
any jurisdiction, at the earliest practicable moment.

              (e) Furnish to each Holder and their Special Counsel, without
charge (i) at least one conformed copy of each Registration Statement and each
amendment thereto, including financial statements and schedules and (ii) all
documents incorporated or deemed to be incorporated therein by reference, and
all exhibits to the extent requested by such Person (including those previously
furnished or incorporated by reference) promptly after the filing of such
documents with the Commission; provided, that the Company shall have no
obligation to provide any document pursuant to this clause (ii) that is
available on the EDGAR system.

              (f) Subject to the terms of Section 6(d), the Company shall
promptly deliver to each Holder and their Special Counsel, without charge, as
many copies of the Prospectus or Prospectuses (including each form of
prospectus) and each amendment or supplement thereto as such Persons may
reasonably request. The Company hereby consents to the use of such Prospectus
and each amendment or supplement thereto by each of the selling Holders in
connection with the offering and sale of the Registrable Securities covered by
such Prospectus and any amendment or supplement thereto.

              (g) Prior to any public offering of Registrable Securities, use
its best efforts to register or qualify or cooperate with the selling Holders
and their Special Counsel in connection with the registration or qualification
(or exemption from such registration or



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qualification) of such Registrable Securities for offer and sale under the
securities or Blue Sky laws of such jurisdictions within the United States as
any Holder requests in writing, to keep each such registration or qualification
(or exemption therefrom) effective during the Effectiveness Period and to do any
and all other acts or things necessary or advisable to enable the disposition in
such jurisdictions of the Registrable Securities covered by a Registration
Statement; provided, that the Company shall not be required to qualify generally
to do business in any jurisdiction where it is not then so qualified or subject
the Company to any material tax in any such jurisdiction where it is not then so
subject.

              (h) Cooperate with the Holders to facilitate the timely
preparation and delivery of certificates representing Registrable Securities to
be delivered to a transferee pursuant to a Registration Statement, which
certificates shall be free, to the extent permitted by the Purchase Agreement,
of all restrictive legends, and to enable such Registrable Securities to be in
such denominations and registered in such names as any such Holders may request.

              (i) Upon the occurrence of any event contemplated by Section
3(c)(v), as promptly as reasonably possible, prepare a supplement or amendment,
including a post-effective amendment, to the Registration Statement or a
supplement to the related Prospectus or any document incorporated or deemed to
be incorporated therein by reference, and file any other required document so
that, as thereafter delivered, neither the Registration Statement nor such
Prospectus will contain an untrue statement of a material fact or omit to state
a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading.

              (j) Comply with all applicable rules and regulations of the
Commission.

              (k) The Company may require each selling Holder to furnish to the
Company a certified statement as to the number of shares of Common Stock
beneficially owned by such Holder and, if requested by the Commission, the
controlling person thereof.

         4. Registration Expenses. All fees and expenses incident to the
performance of or compliance with this Agreement by the Company shall be borne
by the Company whether or not any Registrable Securities are sold pursuant to
the Registration Statement. The fees and expenses referred to in the foregoing
sentence shall include, without limitation, (i) all registration and filing fees
(including, without limitation, fees and expenses (A) with respect to filings
required to be made with the Trading Market on which the Common Stock is then
listed for trading, and (B) in compliance with applicable state securities or
Blue Sky laws), (ii) printing expenses (including, without limitation, expenses
of printing certificates for Registrable Securities and of printing prospectuses
if the printing of prospectuses is reasonably requested by the holders of a
majority of the Registrable Securities included in the Registration Statement),
(iii) messenger, telephone and delivery expenses, (iv) fees and disbursements of
counsel for the Company and $10,000 of the fees and disbursements of Special
Counsel for the Holders, (v) Securities Act liability insurance, if the Company
so desires such insurance, and (vi) fees and expenses of all other Persons
retained by the Company in connection with the consummation of the transactions
contemplated by this Agreement. In addition, the Company shall be responsible
for all of its internal expenses incurred in connection with the consummation of
the transactions



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contemplated by this Agreement (including, without limitation, all salaries and
expenses of its officers and employees performing legal or accounting duties),
the expense of any annual audit and the fees and expenses incurred in connection
with the listing of the Registrable Securities on any securities exchange as
required hereunder.

         5. Indemnification

              (a) Indemnification by the Company. The Company shall,
notwithstanding any termination of this Agreement, indemnify and hold harmless
each Holder, the officers, directors, agents, brokers (including brokers who
offer and sell Registrable Securities as principal as a result of a pledge or
any failure to perform under a margin call of Common Stock), investment advisors
and employees of each of them, each Person who controls any such Holder (within
the meaning of Section 15 of the Securities Act or Section 20 of the Exchange
Act) and the officers, directors, agents and employees of each such controlling
Person, to the fullest extent permitted by applicable law, from and against any
and all losses, claims, damages, liabilities, costs (including, without
limitation, reasonable costs of preparation and reasonable attorneys' fees) and
expenses (collectively, "Losses"), as incurred, arising out of or relating to
any untrue or alleged untrue statement of a material fact contained in the
Registration Statement, any Prospectus or in any amendment or supplement thereto
arising out of or relating to any omission or alleged omission of a material
fact required to be stated therein or necessary to make the statements therein
(in the case of any Prospectus or supplement thereto, in light of the
circumstances under which they were made) not misleading, except to the extent,
but only to the extent, that (1) such untrue statements or omissions are based
solely upon information regarding such Holder furnished in writing to the
Company by such Holder expressly for use therein, or to the extent that such
information relates to such Holder or such Holder's proposed method of
distribution of Registrable Securities and was reviewed and expressly approved
in writing by such Holder expressly for use in the Registration Statement, such
Prospectus or in any amendment or supplement thereto (it being understood that
the Holder has approved Annex A hereto for this purpose) or (2) in the case of
an occurrence of an event of the type specified in Section 3(c)(ii)-(v), the use
by such Holder of an outdated or defective Prospectus after the Company has
notified such Holder in writing that the Prospectus is outdated or defective and
prior to the receipt by such Holder of the Advice contemplated in Section 6(d).
The Company shall notify the Holders promptly of the institution, threat or
assertion of any Proceeding of which the Company is aware in connection with the
transactions contemplated by this Agreement.

              (b) Indemnification by Holders. Each Holder shall, severally and
not jointly, indemnify and hold harmless the Company, its directors, officers,
agents and employees, each Person who controls the Company (within the meaning
of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the
directors, officers, agents or employees of such controlling Persons, to the
fullest extent permitted by applicable law, from and against all Losses, as
incurred, arising solely out of or based solely upon: (x) such Holder's failure
to comply with the prospectus delivery requirements of the Securities Act
(provided that the Company has delivered a Prospectus to such Holder or a
Prospectus is otherwise available via the EDGAR system) or (y) any untrue
statement of a material fact contained in any Registration Statement, any
Prospectus, or in any amendment or supplement thereto, or arising solely out of
or based solely upon any omission of a material fact required to be stated
therein or necessary to



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make the statements therein not misleading to the extent, but only to the
extent, that such untrue statement or omission is contained in any information
so furnished in writing by such Holder to the Company specifically for inclusion
in such Registration Statement or such Prospectus or to the extent that (1) such
untrue statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use
therein, or to the extent that such information relates to such Holder or such
Holder's proposed method of distribution of Registrable Securities and was
reviewed and expressly approved in writing by such Holder expressly for use in
the Registration Statement (it being understood that the Holder has approved
Annex A hereto for this purpose), such Prospectus or in any amendment or
supplement thereto or (2) in the case of an occurrence of an event of the type
specified in Section 3(c)(ii)-(v), the use by such Holder of an outdated or
defective Prospectus after the Company has notified such Holder in writing that
the Prospectus is outdated or defective and prior to the receipt by such Holder
of the Advice contemplated in Section 6(d). In no event shall the liability of
any selling Holder hereunder be greater in amount than the dollar amount of the
net proceeds received by such Holder upon the sale of the Registrable Securities
giving rise to such indemnification obligation.

              (c) Conduct of Indemnification Proceedings. If any Proceeding
shall be brought or asserted against any Person entitled to indemnity hereunder
(an "INDEMNIFIED PARTY"), such Indemnified Party shall promptly notify the
Person from whom indemnity is sought (the "INDEMNIFYING PARTY") in writing, and
the Indemnifying Party shall assume the defense thereof, including the
employment of counsel reasonably satisfactory to the Indemnified Party and the
payment of all fees and expenses incurred in connection with defense thereof;
provided, that the failure of any Indemnified Party to give such notice shall
not relieve the Indemnifying Party of its obligations or liabilities pursuant to
this Agreement, except (and only) to the extent that such failure shall have
proximately and materially adversely prejudiced the Indemnifying Party.

         An Indemnified Party shall have the right to employ separate counsel in
any such Proceeding and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such Indemnified Party or
Parties unless: (1) the Indemnifying Party has agreed in writing to pay such
fees and expenses; (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (3) the named
parties to any such Proceeding (including any impleaded parties) include both
such Indemnified Party and the Indemnifying Party, and such Indemnified Party
shall have been advised in writing by counsel that a conflict of interest is
likely to exist if the same counsel were to represent such Indemnified Party and
the Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at the
expense of the Indemnifying Party, the Indemnifying Party shall not have the
right to assume the defense thereof and such counsel shall be at the expense of
the Indemnifying Party) provided, that the Indemnifying Party shall not be
liable for the fees and expenses of more than one separate firm of attorneys at
any time for all indemnified parties. The Indemnifying Party shall not be liable
for any settlement of any such Proceeding effected without its written consent,
which consent shall not be unreasonably withheld. No Indemnifying Party shall,
without the prior written consent of the Indemnified Party, effect any
settlement of any pending Proceeding in respect of which any Indemnified Party
is a party, unless such settlement includes an unconditional release



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of such Indemnified Party from all liability on claims that are the subject
matter of such Proceeding.

         All fees and expenses of the Indemnified Party (including reasonable
fees and expenses to the extent incurred in connection with investigating or
preparing to defend such Proceeding in a manner not inconsistent with this
Section) shall be paid to the Indemnified Party, as incurred, within ten Trading
Days of written notice thereof to the Indemnifying Party (regardless of whether
it is ultimately determined that an Indemnified Party is not entitled to
indemnification hereunder; provided, that the Indemnified Party shall reimburse
all such fees and expenses to the extent it is finally judicially determined
that such Indemnified Party is not entitled to indemnification hereunder).

              (d) Contribution. If a claim for indemnification under Section
5(a) or 5(b) is unavailable to an Indemnified Party (by reason of public policy
or otherwise), then each Indemnifying Party, in lieu of indemnifying such
Indemnified Party, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such Losses, in such proportion as is
appropriate to reflect the relative fault of the Indemnifying Party and
Indemnified Party in connection with the actions, statements or omissions that
resulted in such Losses as well as any other relevant equitable considerations.
The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission of a material fact, has been taken or made by, or relates to
information supplied by, such Indemnifying Party or Indemnified Party, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such action, statement or omission. The amount paid or
payable by a party as a result of any Losses shall be deemed to include, subject
to the limitations set forth in Section 5(c), any reasonable attorneys' or other
reasonable fees or expenses incurred by such party in connection with any
Proceeding to the extent such party would have been indemnified for such fees or
expenses if the indemnification provided for in this Section was available to
such party in accordance with its terms.

         The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 5(d), no Holder shall be required
to contribute, in the aggregate, any amount in excess of the amount by which the
proceeds actually received by such Holder from the sale of the Registrable
Securities subject to the Proceeding exceeds the amount of any damages that such
Holder has otherwise been required to pay by reason of such untrue or alleged
untrue statement or omission or alleged omission.

         The indemnity and contribution agreements contained in this Section re
in addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties.

         6. Miscellaneous

              (a) Remedies. In the event of a breach by the Company or by a
Holder, of any of their obligations under this Agreement, each Holder or the
Company, as the



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case may be, in addition to being entitled to exercise all rights granted by law
and under this Agreement, including recovery of damages, will be entitled to
specific performance of its rights under this Agreement. The Company and each
Holder agree that monetary damages would not provide adequate compensation for
any losses incurred by reason of a breach by it of any of the provisions of this
Agreement and hereby further agrees that, in the event of any action for
specific performance in respect of such breach, it shall waive the defense that
a remedy at law would be adequate.

              (b) No Piggyback on Registrations. Except as and to the extent
specified in Schedule 6(b) hereto, neither the Company nor any of its security
holders (other than the Holders in such capacity pursuant hereto) may include
securities of the Company in the Registration Statement other than the
Registrable Securities, and the Company shall not after the date hereof enter
into any agreement providing any such right to any of its security holders.
Except as and to the extent specified in Schedule 6(b) hereto, the Company has
not previously entered into any agreement granting any registration rights with
respect to any of its securities to any Person which have not been fully
satisfied.

              (c) Compliance. Each Holder covenants and agrees that it will
comply with the prospectus delivery requirements of the Securities Act as
applicable to it in connection with sales of Registrable Securities pursuant to
the Registration Statement, provided that the Company has delivered a Prospectus
to such Holder or a Prospectus is otherwise available via the EDGAR system.

              (d) Discontinued Disposition. Each Holder agrees by its
acquisition of such Registrable Securities that, upon receipt of a notice from
the Company of the occurrence of any event of the kind described in Section
3(c), such Holder will forthwith discontinue disposition of such Registrable
Securities under the Registration Statement until such Holder's receipt of the
copies of the supplemented Prospectus and/or amended Registration Statement or
until it is advised in writing (the "ADVICE") by the Company that the use of the
applicable Prospectus may be resumed, and, in either case, has received copies
of any additional or supplemental filings that are incorporated or deemed to be
incorporated by reference in such Prospectus or Registration Statement. The
Company may provide appropriate stop orders to enforce the provisions of this
paragraph.

              (e) Piggy-Back Registrations. If at any time during the
Effectiveness Period there is not an effective Registration Statement covering
all of the Registrable Securities and the Company shall determine to prepare and
file with the Commission a registration statement relating to an offering for
its own account or the account of others under the Securities Act of any of its
equity securities, other than on Form S-4 or Form S-8 (each as promulgated under
the Securities Act) or their then equivalents relating to equity securities to
be issued solely in connection with any acquisition of any entity or business or
equity securities issuable in connection with stock option or other employee
benefit plans, then the Company shall send to each Holder written notice of such
determination and, if within fifteen days after receipt of such notice, any such
Holder shall so request in writing, the Company shall include in such
registration statement all or any part of such Registrable Securities such
holder requests to be registered, subject to customary underwriter cutbacks
applicable to all holders of registration rights.



                                       10
<PAGE>   11

              (f) Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the same shall be in writing and signed by the Company
and the Holders of the then outstanding Registrable Securities. Notwithstanding
the foregoing, a waiver or consent to depart from the provisions hereof with
respect to a matter that relates exclusively to the rights of certain Holders
and that does not directly or indirectly affect the rights of other Holders may
be given by Holders of at least a majority of the Registrable Securities to
which such waiver or consent relates; provided, however, that the provisions of
this sentence may not be amended, modified, or supplemented except in accordance
with the provisions of the immediately preceding sentence.

              (g) Notices. Any and all notices or other communications or
deliveries required or permitted to be provided hereunder shall be in writing
and shall be deemed given and effective on the earliest of (i) the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile telephone number specified in this Section prior to 6:30 p.m. (New
York City time) on a Trading Day, (ii) the Trading Day after the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile telephone number specified in this Agreement later than 6:30 p.m. (New
York City time) on any date and earlier than 11:59 p.m. (New York City time) on
such date, (iii) the Trading Day following the date of mailing, if sent by
nationally recognized overnight courier service, or (iv) upon actual receipt by
the party to whom such notice is required to be given. The address for such
notices and communications shall be as follows:

         If to the Company:     HYSEQ, Inc.
                                670 Almanor Avenue,
                                Sunnyvale, California 94085
                                Facsimile No.:  (408) 524-8141
                                Attn: President

         With a copy to:        Latham & Watkins
                                135 Commonwealth Drive
                                Menlo Park, California 94025
                                Attn: Alan C. Mendelson
                                Facsimile No.:  (650) 463-2600

         If to a Purchaser:     To the address set forth under such Purchaser's
                                name on the signature pages hereto.

         With a copy to:        Robinson Silverman Pearce Aronsohn & Berman LLP
                                1290 Avenue of the Americas
                                New York, NY 10104
                                Facsimile No.: (212) 541-4630 and (212) 541-1432
                                Attn: Eric L. Cohen, Esq.



                                       11
<PAGE>   12

         If to any other Person who is then the registered Holder:

                                To the address of such Holder as it appears in
                                the stock transfer books of the Company

or such other address as may be designated in writing hereafter, in the same
manner, by such Person.

              (h) Successors and Assigns. This Agreement shall inure to the
benefit of and be binding upon the successors and permitted assigns of each of
the parties and shall inure to the benefit of each Holder. The Company may not
assign its rights or obligations hereunder without the prior written consent of
each Holder. Each Holder may assign their respective rights hereunder in the
manner and to the Persons as permitted under the Purchase Agreement.

              (i) Execution and Counterparts. This Agreement may be executed in
any number of counterparts, each of which when so executed shall be deemed to be
an original and, all of which taken together shall constitute one and the same
Agreement. In the event that any signature is delivered by facsimile
transmission, such signature shall create a valid binding obligation of the
party executing (or on whose behalf such signature is executed) the same with
the same force and effect as if such facsimile signature were the original
thereof.

              (j) Governing Law. All questions concerning the construction,
validity, enforcement and interpretation of this Agreement shall be governed by
and construed and enforced in accordance with the internal laws of the State of
New York, without regard to the principles of conflicts of law thereof. Each
party agrees that all legal proceedings concerning the interpretations,
enforcement and defense of the transactions contemplated by this Agreement
(whether brought against a party hereto or its respective affiliates, directors,
officers, shareholders, employees or agents) shall be commenced in the state and
federal courts sitting in the City of New York, Borough of Manhattan (the "NEW
YORK COURTS"). Each party hereto hereby irrevocably submits to the exclusive
jurisdiction of the New York Courts for the adjudication of any dispute
hereunder or in connection herewith or with any transaction contemplated hereby
or discussed herein (including with respect to the enforcement of this
Agreement), and hereby irrevocably waives, and agrees not to assert in any suit,
action or proceeding, any claim that it is not personally subject to the
jurisdiction of any such court, or such New York Courts are improper or
inconvenient venue for such proceeding. Each party hereby irrevocably waives
personal service of process and consents to process being served in any such
suit, action or proceeding by mailing a copy thereof via registered or certified
mail or overnight delivery (with evidence of delivery) to such party at the
address in effect for notices to it under this Agreement and agrees that such
service shall constitute good and sufficient service of process and notice
thereof. Nothing contained herein shall be deemed to limit in any way any right
to serve process in any manner permitted by law. Each party hereto (including
its affiliates, agents, officers, directors and employees) hereby irrevocably
waives, to the fullest extent permitted by applicable law, any and all right to
trial by jury in any legal proceeding arising out of or relating to this
Agreement or the transactions contemplated hereby. If either party shall
commence an action or proceeding to enforce any provisions of this Agreement,
then the prevailing party in such action or proceeding shall be reimbursed by
the other party for its attorneys fees and other costs and expenses incurred
with the investigation, preparation and prosecution of such action or
proceeding.

                                       12
<PAGE>   13

              (k) Cumulative Remedies. The remedies provided herein are
cumulative and not exclusive of any remedies provided by law.

              (l) Severability. If any term, provision, covenant or restriction
of this Agreement is held by a court of competent jurisdiction to be invalid,
illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their reasonable efforts to find and employ an alternative
means to achieve the same or substantially the same result as that contemplated
by such term, provision, covenant or restriction. It is hereby stipulated and
declared to be the intention of the parties that they would have executed the
remaining terms, provisions, covenants and restrictions without including any of
such that may be hereafter declared invalid, illegal, void or unenforceable.

              (m) Headings. The headings in this Agreement are for convenience
of reference only and shall not limit or otherwise affect the meaning hereof.

              (n) Independent Nature of Purchasers' Obligations and Rights. The
obligations of each Purchaser hereunder is several and not joint with the
obligations of any other Purchaser hereunder, and no Purchaser shall be
responsible in any way for the performance of the obligations of any other
Purchaser hereunder. Nothing contained herein or in any other agreement or
document delivered at any closing, and no action taken by any Purchaser pursuant
hereto or thereto, shall be deemed to constitute the Purchasers as a
partnership, an association, a joint venture or any other kind of entity, or
create a presumption that the Purchasers are in any way acting in concert with
respect to such obligations or the transactions contemplated by this Agreement.
Each Purchaser shall be entitled to protect and enforce its rights, including
without limitation the rights arising out of this Agreement, and it shall not be
necessary for any other Purchaser to be joined as an additional party in any
proceeding for such purpose.

                   [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                           SIGNATURE PAGES TO FOLLOW]



                                       13
<PAGE>   14

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

                                        HYSEQ, INC.


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


                   [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                     SIGNATURE PAGES OF PURCHASER TO FOLLOW]




                                       14
<PAGE>   15


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

                                        [Purchaser]

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


                                        Address for Notice:

                                        [   ]

                                        With a copy to:

                                        [   ]



                                       15
<PAGE>   16
                                                                         Annex A

                              PLAN OF DISTRIBUTION

         The Selling Stockholders and any of their pledgees, assignees and
successors-in-interest may, from time to time, sell any or all of their shares
of Common Stock on any stock exchange, market or trading facility on which the
shares are traded or in private transactions. These sales may be at fixed or
negotiated prices. The Selling Stockholders may use any one or more of the
following methods when selling shares:

o    ordinary brokerage transactions and transactions in which the broker-dealer
     solicits purchasers;

o    block trades in which the broker-dealer will attempt to sell the shares as
     agent but may position and resell a portion of the block as principal to
     facilitate the transaction;

o    purchases by a broker-dealer as principal and resale by the broker-dealer
     for its account;

o    an exchange distribution in accordance with the rules of the applicable
     exchange;

o    privately negotiated transactions;

o    short sales;

o    broker-dealers may agree with the Selling Stockholders to sell a specified
     number of such shares at a stipulated price per share;

o    a combination of any such methods of sale; and

o    any other method permitted pursuant to applicable law.

         The Selling Stockholders may also sell shares under Rule 144 under the
Securities Act, if available, rather than under this prospectus.

         Broker-dealers engaged by the Selling Stockholders may arrange for
other brokers-dealers to participate in sales. Broker-dealers may receive
commissions or discounts from the Selling Stockholders (or, if any broker-dealer
acts as agent for the purchaser of shares, from the purchaser) in amounts to be
negotiated. The Selling Stockholders do not expect these commissions and
discounts to exceed what is customary in the types of transactions involved.

         The Selling Stockholder may from time to time pledge or grant a
security interest in some or all of the Shares or common stock or Warrants owned
by them and, if they default in the performance of their secured obligations,
the pledgees or secured parties may offer and sell the shares of common stock
from time to time under this prospectus, or under an amendment to this
prospectus under Rule 424(b)(3) or other applicable provision of the Securities
Act of 1933 amending the list of selling stockholders to include the pledgee,
transferee or other successors in interest as selling stockholders under this
prospectus.



                                       16
<PAGE>   17

         The Selling Stockholders also may transfer the shares of common stock
in other circumstances, in which case the transferees, pledgees or other
successors in interest will be the selling beneficial owners for purposes of
this prospectus.

         The Selling Stockholders and any broker-dealers or agents that are
involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales. In such event, any
commissions received by such broker-dealers or agents and any profit on the
resale of the shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. The Selling Stockholders have
informed the Company that they do not have any agreement or understanding,
directly or indirectly, with any person to distribute the Common Stock.

         The Company has advised the Selling Stockholders that they are required
to comply with Regulation M promulgated under the Securities and Exchange Act
during such time as they may be engaged in a distribution of the shares. With
some exceptions, Regulation M precludes any Selling Stockholders, any affiliated
purchasers and any broker-dealer or other person who participates in such
distribution from bidding for or purchasing, or attempting to induce any person
to bid for or purchase any security that is the subject of the distribution
until the entire distribution is complete. Regulation M also prohibits any bids
or purchases made in order to stabilize the price of a security in connection
with the distribution of that security. All of the foregoing may affect the
marketability of the common stock.

         The Company is required to pay all fees and expenses incident to the
registration of the shares, including $10,000 of fees and disbursements of
counsel to the Selling Stockholders. The Company has agreed to indemnify the
Selling Stockholders against certain losses, claims, damages and liabilities,
including liabilities under the Securities Act.


                                       17