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Exhibit 4.3  


 
 

REGISTRATION RIGHTS AGREEMENT    
    


        This Registration Rights Agreement (this "Agreement") is made and entered into as of July 2, 2003, by and
among Advanced Magnetics, Inc., a Delaware 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, with respect to the Registration Statement required to be filed hereunder, the earlier of (a) the 120th
calendar day following the Closing Date and (b) the fifth Trading Day following the date on which the Company is notified by the Commission that the Registration Statement will not be reviewed
or is no longer subject to further review and comments. 


        "Effectiveness Period" shall have the meaning set forth in Section 2(a). 


        "Filing Date" means, with respect to the Registration Statement required to be filed hereunder, the 30th calendar 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). 



        "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 the 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 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 the Warrant Shares, together with any shares of Common Stock issued or issuable upon any
stock split, dividend or other distribution, recapitalization or similar event with respect to the foregoing or in connection with any anti-dilution provisions in the Warrant. 


        "Registration Statement" means the registration statements required to be filed hereunder, including (in each case) the Prospectus,
amendments and supplements to the registration statement 



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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 the
registration statement. 


        "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 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 effect as such Rule. 


        "Securities Act" means the Securities Act of 1933, as amended. 




        2.    Registration.    



        (a)   On
or prior to the Filing Date, the Company shall prepare and file with the Commission the Registration Statement covering the resale of all of the Registrable
Securities for an offering to be made on a continuous basis pursuant to Rule 415. The Registration Statement required hereunder 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 the registration shall be on another appropriate form in accordance herewith). The
Registration Statement required hereunder shall contain (except if otherwise directed by the Holders) the "Plan of Distribution" attached hereto as  Annex A. The Company shall cause the Registration Statement to become effective and remain effective as provided herein. The Company shall use its
commercially reasonable 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 not later than
the Effectiveness Date, and shall use its commercially reasonable efforts to keep the Registration Statement continuously effective under the Securities Act until the date which is two years after the
Closing Date or such earlier date when all Registrable Securities covered by the Registration Statement (a) have been sold pursuant to the Registration Statement or an exemption from the
registration requirements of the Securities Act or (b) may be sold without volume restrictions pursuant to Rule 144 (the "Effectiveness
Period"). 


        (b)   If:
(i) a Registration Statement is not filed on or prior to its Filing Date (if the Company files a Registration Statement without affording the Holder the
opportunity to review and comment on the same as required by Section 3(a), the Company shall not be deemed to have satisfied this clause (i)); provided,
however, that if a Holder fails to provide the Company with any information that is required to be provided in the Registration Statement with respect to such Holder pursuant
to Section 3(k), then the Filing Date shall be extended until two Trading Days following the date of receipt by the Company of such required information, or (ii) the Company fails to
file with the Commission a request for acceleration in accordance with Rule 461 promulgated under the Securities Act, within five Trading 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 (iii) prior to the date when such Registration
Statement is first declared effective by the Commission, the Company fails to file a pre-effective amendment and otherwise respond in writing to comments made by the Commission in
respect of such Registration Statement within ten Trading Days after the receipt of comments by or notice from the Commission that such amendment is required in order for a Registration Statement to
be declared effective, or (iv) a Registration Statement filed or required to be filed hereunder is not declared effective by the Commission on or before the Effectiveness Date, or
(v) after a Registration Statement is first declared effective by the Commission, it ceases for any reason to remain continuously effective as to all Registrable Securities for which it is
required to be effective, or the Holders are not permitted to utilize the Prospectus therein to resell such Registrable Securities, for in any such cases ten Trading Days (which need not be
consecutive 



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days)
in the aggregate during any 12-month period (any such failure or breach being referred to as an "Event," and for purposes of
clause (i) or (iv) the date on which such Event occurs, or for purposes of clause (ii) the date on which such five Trading Day period is exceeded, or for purposes of
clause (iii) the date which such ten Trading Day period is exceeded, or for purposes of clause (v) the date on which such ten Trading Day period is exceeded, being referred to as
"Event Date"), then in addition to any other rights the Holders may have hereunder or under applicable law: (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 2% of the aggregate purchase price paid by such Holder pursuant to the Purchase Agreement for
any Registrable Securities then held by such Holder; and (y) on each monthly anniversary of each such Event Date (if the applicable Event shall not have been cured by such date) 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% of the aggregate purchase price paid by such Holder pursuant
to the Purchase Agreement for any Registrable Securities then held by such Holder. If the 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 18% 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 three Trading Days prior to the filing of the Registration Statement or any related Prospectus or any amendment or supplement thereto, (i) furnish
to the Holders copies of all such documents proposed to be filed (including documents incorporated or deemed incorporated by reference to the extent requested by such Person), which documents will be
subject to the review of such Holders, 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 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; (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 fifteen 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, upon request, 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 as promptly as reasonably possible (and, in the case of (i)(A) below, not less than two Trading Days prior to
such filing) and (if requested by any such Person) confirm such notice in writing promptly following the day (i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment to the Registration 



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Statement
is proposed to be filed; (B) when the Commission notifies the Company whether there will be a "review" of the Registration Statement and whenever the Commission comments in writing on
the Registration Statement (the Company shall upon request 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 during the period of effectiveness of the Registration Statement for amendments or supplements to the Registration Statement or Prospectus or for additional information; (iii) of the
issuance by the Commission or any other federal or state governmental authority 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 revisions to the Registration Statement, Prospectus or other documents 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 commercially reasonable 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, without charge, at least one conformed copy of the Registration Statement and each amendment thereto, including financial statements and
schedules, all documents incorporated or deemed to be incorporated therein by reference to the extent requested by such Person, 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. 


        (f)    Promptly
deliver to each Holder, 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 in connection with resales by the Holder of Registrable Securities. 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, except after the giving of any notice pursuant to Section 3(c). 


        (g)   Prior
to any resale of Registrable Securities by a Holder, use its commercially reasonable efforts to register or qualify or cooperate with the selling Holders in
connection with the registration or qualification (or exemption from the Registration or qualification) of such Registrable Securities for the resale by the Holder under the securities or Blue Sky
laws of such jurisdictions within the United States as any Holder reasonably requests in writing, to keep each the Registration or qualification (or exemption therefrom) effective during the
Effectiveness Period and to do any and all other acts or things reasonably necessary to enable the disposition in such jurisdictions of the Registrable Securities covered by the Registration
Statement; provided, that the Company shall not be required to qualify generally to do business in any jurisdiction where it is 



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not
then so qualified, subject the Company to any material tax in any such jurisdiction where it is not then so subject or file a general consent to service of process in any such jurisdiction. 



        (h)   If
requested by the Holders, cooperate with the Holders to facilitate the timely preparation and delivery of certificates representing Registrable Securities to be
delivered to a transferee pursuant to the 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 required by the Commission, the person thereof that has voting and dispositive control over the Shares. 




        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,
(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 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 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 attorneys' fees) and expenses (collectively,  "Losses"), as incurred, to the 



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extent
arising out of or relating to any untrue or alleged untrue statement of a material fact contained in the Registration Statement, any Prospectus or any form of prospectus or in any amendment or
supplement thereto or in any preliminary prospectus, or 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 form of 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 such form of Prospectus or in any amendment or supplement thereto (it being understood that the Holder has approved Annex A
hereto for this purpose and the names and addresses in the Transaction Documents) 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, to the extent arising out of
or based upon: (x) such Holder's failure to comply with the prospectus delivery requirements of the Securities Act or (y) any untrue statement of a material fact contained in any
Registration Statement, any Prospectus, or any form of prospectus, or in any amendment or supplement thereto or in any preliminary prospectus, or arising out of or relating to any omission of a
material fact required to be stated therein or necessary to make the statements therein not misleading (i) 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 the Registration Statement or such Prospectus or (ii) 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 such form of 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 have the right to assume the defense thereof, including the employment of counsel
reasonably satisfactory to the Indemnified Party and the payment of all 



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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 it shall be finally determined by a court of competent jurisdiction (which determination is not subject to appeal or
further review) that such failure shall have 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 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 the reasonable fees and expenses of one separate
counsel for all Indemnified Parties shall be at the expense of the Indemnifying Party). 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 of such Indemnified Party from all liability on claims that are the subject
matter of such Proceeding. 


        All
reasonable 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;  provided,
that the Indemnified Party shall promptly reimburse the Indemnifying Party for that portion of such fees and expenses applicable to such
actions for which such Indemnified Party is not entitled to indemnification hereunder, determined based upon the relative faults of the parties. 


        (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. 



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        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, except in the
case of fraud by such Holder. The indemnity and contribution agreements contained in this Section are 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 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.    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 a 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 set forth in the SEC Reports, no Person has any right to cause the Company to effect the registration under the
Securities Act of any securities of the Company. The Company shall not file any other registration statement until after the Effective Date. 


        (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. 



        (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 the stock option or other employee benefit plans, then the Company shall send to each Holder a written notice of such 



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determination
and, if within fifteen days after the date 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. 



        (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 each Holder
of the then outstanding Registrable Securities. 


        (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 number provided for below 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 number provided for below 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 delivered and addressed as set forth in the Purchase Agreement 


        (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. Each Holder may assign their respective rights hereunder in the manner and to the Persons as permitted under the
Purchase Agreement to a transferee of any Securities. 


        (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 exclusively in the state and federal courts sitting in the City of New York, New York. Each party hereto hereby
irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of New York, New York 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 the any 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, that such suit, action or proceeding is improper. Each party hereto hereby irrevocably
waives personal service of process and consents to process being served in any such suit, action or proceeding by delivering a copy thereof via 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 hereby irrevocably waives, to the fullest extent 



9





 




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. 



        (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 commercially 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. 



10





 
EXHIBIT A  


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



	 	 	ADVANCED MAGNETICS, INC.
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[PURCHASERS'
SIGNATURE PAGES TO FOLLOW] 


11





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	BONANZA MASTER FUND LTD.
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


12





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	GROVE STREET CAPITAL ADVISERS, INC.
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


13





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	MAINFIELD ENTERPRISES INC.
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


14





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	SMITHFIELD FIDUCIARY LLC
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


15





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	VERTICAL VENTURES INVESTMENTS, LLC
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


16





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	BAYSTAR CAPITAL II, LP
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


17





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	SDS MERCHANT FUND, LP
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




[ADDITIONAL
PURCHASER SIGNATURES FOLLOW] 


18





 
[PURCHASER'S
SIGNATURE PAGE TO RRA] 



	 	 	GRYPHON MASTER FUND, L.P.
	

 	
 	
By:	

 
	 	 	 	
 Name:

Title:




19





 
 
 

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: 



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



	•
	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;



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



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



	•
	privately
negotiated transactions;



	•
	settlement
of short sales;



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



	•
	a
combination of any such methods of sale; and



	•
	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 Stockholders may from time to time pledge or grant a security interest in some or all of the shares of common stock 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. 


        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. Each Selling Stockholder has informed the Company that it does not have any agreement or understanding, directly or indirectly, with any person to
distribute the Common Stock. 



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


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REGISTRATION RIGHTS AGREEMENT

ANNEX A