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                                                                     EXHIBIT 4.6

                               SILICON VALLEY BANK
                          REGISTRATION RIGHTS AGREEMENT

         THIS REGISTRATION RIGHTS AGREEMENT is entered into as of May 8, 2003,
by and between Silicon Valley Bank ("SVB") and the Company whose name appears on
the last page of this Agreement.

                                    RECITALS

         A. Concurrently with the execution of this Agreement, the Company is
issuing a warrant to purchase stock to SVB (the "Warrant") pursuant to which SVB
has the right to acquire from the Company the Shares (as defined in the
Warrant).

         B. By this Agreement, the SVB and the Company desire to set forth the
registration rights of the Shares all as provided herein.

         NOW, THEREFORE, in consideration of the mutual promises, covenants and
conditions hereinafter set forth, the parties hereto mutually agree as follows:

         1. Registration Rights. The Company covenants and agrees as follows:

                  1.1 Definitions. For purposes of this Section 1:

                           (a) The term "register," "registered," and
"registration" refer to a registration effected by preparing and filing a
registration statement or similar document in compliance with the Securities Act
of 1933, as amended (the "Securities Act"), and the declaration or ordering of
effectiveness of such registration statement or document;

                           (b) The term "Registrable Securities" means (i) the
Shares (if Common Stock) or all shares of Common Stock of the Company issuable
or issued upon conversion of the Shares and (ii) any Common Stock of the Company
issued as (or issuable upon the conversion or exercise of any warrant, right or
other security which is issued as) a dividend or other distribution with respect
to, or in exchange for or in replacement of, any stock referred to in (i).

                           (c) The terms "Holder" or "Holders" means the SVB or
qualifying transferees under subsection 1.8 hereof who hold Registrable
Securities.

                           (d) The term "SEC" means the Securities and Exchange
Commission.

                  1.2 Company Registration.

                           (a) Registration. If at any time or from time to
time, the Company shall determine to register any of its securities, for its own
account or the account of any of its shareholders, other than a registration on
Form S-1 or S-8 or Form D relating solely to employee stock option or purchase
plans, or a registration on Form S-4 relating solely to an SEC Rule 145
transaction, or a registration on any other form (other than Form S-1, S-2, S-3
or S-18, or their

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successor forms) or any successor to such forms, which does not include
substantially the same information as would be required to be included in a
registration statement covering the sale of Registrable Securities, the Company
will:

                                    (i) promptly give to each Holder written
notice thereof (which shall include a list of the jurisdictions in which the
Company intends to attempt to qualify such securities under the applicable blue
sky or other state securities laws); and

                                    (ii)include in such registration (and
compliance), and in any underwriting involved therein, all the Registrable
Securities specified in a written request or requests, made within 30 days after
receipt of such written notice from the Company, by any Holder or Holders,
except as set forth in subsection 1.2(b) below.

                           (b) Underwriting. If the registration of which the
Company gives notice is for a registered public offering involving an
underwriting, the Company shall so advise the Holders as a part of the written
notice given pursuant to subsection 1.2(a)(i). In such event the right of any
Holder to registration pursuant to this subsection 1.2 shall be conditioned upon
such Holder's participation in such underwriting and the inclusion of such
Holder's Registrable Securities in the underwriting to the extent provided
herein. All Holders proposing to distribute their securities through such
underwriting shall (together with the Company and the other shareholders
distributing their securities through such underwriting) enter into an
underwriting agreement in customary form with the underwriter or underwriters
selected for such underwriting by the Company.

                  1.3 Expenses of Registration. All expenses incurred in
connection with any registration, qualification or compliance pursuant to this
Section 1 including without limitation, all registration, filing and
qualification fees, printing expenses, fees and disbursements of counsel for the
Company and expenses of any special audits incidental to or required by such
registration, shall be borne by the Company except the Company shall not be
required to pay underwriters' fees, discounts or commissions relating to
Registrable Securities. All expenses of any registered offering not otherwise
borne by the Company shall be borne pro rata among the Holders participating in
the offering and the Company.

                  1.4 Registration Procedures. In the case of each registration,
qualification or compliance effected by the Company pursuant to this
Registration Rights Agreement, the Company will keep each Holder participating
therein advised in writing as to the initiation of each registration,
qualification and compliance and as to the completion thereof. Except as
otherwise provided in subsection 1.3, at its expense the Company will:

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

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

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

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

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

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

                  1.5 Indemnification.

                           (a) The Company will indemnify each Holder of
Registrable Securities and each of its officers, directors and partners, and
each person controlling such Holder, with respect to which such registration,
qualification or compliance has been effected pursuant to this Rights Agreement,
and each underwriter, if any, and each person who controls any underwriter of
the Registrable Securities held by or issuable to such Holder, against all
claims, losses, expenses, damages and liabilities (or actions in respect
thereto) arising out of or based on any untrue statement (or alleged untrue
statement) of a material fact contained in any prospectus, offering circular or
other document (including any related registration statement, notification or
the like) incident to any such registration, qualification or compliance, or
based on any omission (or alleged omission) to state therein a material fact
required to be stated therein or necessary to make the statement therein not
misleading, or any violation or alleged violation by the Company of the
Securities Act, the Securities Exchange Act of 1934, as amended ("Exchange
Act"), or any state securities law applicable to the Company or any rule or
regulation promulgated under the Securities Act, the Exchange Act or any such
state law and relating to action or inaction required of the Company in
connection with any such registration, qualification of compliance, and will

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reimburse each such Holder, each of its officers, directors and partners, and
each person controlling such Holder, each such underwriter and each person who
controls any such underwriter, within a reasonable amount of time after incurred
for any reasonable legal and any other expenses incurred in connection with
investigating, defending or settling any such claim, loss, damage, liability or
action; provided, however, that the indemnity agreement contained in this
subsection 1.5(a) shall not apply to amounts paid in settlement of any such
claim, loss, damage, liability, or action if such settlement is effected without
the consent of the Company (which consent shall not be unreasonably withheld);
and provided further, that the Company will not be liable in any such case to
the extent that any such claim, loss, damage or liability arises out of or is
based on any untrue statement or omission based upon written information
furnished to the Company by an instrument duly executed by such Holder or
underwriter specifically for use therein.

                           (b) Each Holder will, if Registrable Securities held
by or issuable to such Holder are included in the securities as to which such
registration, qualification or compliance is being effected, indemnify the
Company, each of its directors and officers, each underwriter, if any, of the
Company's securities covered by such a registration statement, each person who
controls the Company within the meaning of the Securities Act, and each other
such Holder, each of its officers, directors and partners and each person
controlling such Holder, against all claims, losses, expenses, damages and
liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of a material fact contained in
any such registration statement, prospectus, offering circular or other
document, or any omission (or alleged omission) to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, and will reimburse the Company, such Holders, such directors,
officers, partners, persons or underwriters for any reasonable legal or any
other expenses incurred in connection with investigating, defending or settling
any such claim, loss, damage, liability or action, in each case to the extent,
but only to the extent, that such untrue statement (or alleged untrue statement)
or omission (or alleged omission) is made in such registration statement,
prospectus, offering circular or other document in reliance upon and in
conformity with written information furnished to the Company by an instrument
duly executed by such Holder specifically for use therein; provided, however,
that the indemnity agreement contained in this subsection 1.5(b) shall not apply
to amounts paid in settlement of any such claim, loss, damage, liability or
action if such settlement is effected without the consent of the Holder (which
consent shall not be unreasonably withheld); and provided further, that the
total amount for which any Holder shall be liable under this subsection 1.5(b)
shall not in any event exceed the aggregate proceeds received by such Holder
from the sale of Registrable Securities held by such Holder in such
registration.

                           (c) Each party entitled to indemnification under this
subsection 1.5 (the "Indemnified Party") shall give notice to the party required
to provide indemnification (the "Indemnifying Party") promptly after such
Indemnified Party has actual knowledge of any claim as to which indemnity may be
sought, and shall permit the Indemnifying Party to assume the defense of any
such claim or any litigation resulting therefrom; provided that counsel for the
Indemnifying Party, who shall conduct the defense of such claim or litigation,
shall be approved by the Indemnified Party (whose approval shall not be
unreasonably withheld), and the

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Indemnified Party may participate in such defense at such party's expense; and
provided further, that the failure of any Indemnified Party to give notice as
provided herein shall not relieve the Indemnifying of its obligations hereunder,
unless such failure resulted in prejudice to the Indemnifying Party; and
provided further, that an Indemnified Party (together with all other Indemnified
Parties which may be represented without conflict by one counsel) shall have the
right to retain one separate counsel, with the fees and expenses to be paid by
the Indemnifying Party, if representation of such Indemnified Party by the
counsel retained by the Indemnifying Party would be inappropriate due to actual
or potential differing interests between such Indemnified Party and any other
party represented by such counsel in such proceeding. No Indemnifying Party, in
the defense of any such claim or litigation, shall, except with the consent of
each Indemnified Party, consent to entry of any judgment or enter into any
settlement which does not include as an unconditional term thereof the giving by
the claimant or plaintiff to such Indemnified Party of a release from all
liability in respect to such claim or litigation.

                  1.6 Information by Holder. Any Holder or Holders of
Registrable Securities included in any registration shall promptly furnish to
the Company such information regarding such Holder or Holders and the
distribution proposed by such Holder or Holders as the Company may request in
writing and as shall be required in connection with any registration,
qualification or compliance referred to herein.

                  1.7 Rule 144 Reporting. With a view to making available to
Holders the benefits of certain rules and regulations of the SEC which may
permit the sale of the Registrable Securities to the public without
registration, the Company agrees at all times to:

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

                           (b) file with the SEC in a timely manner all reports
and other documents required of the Company under the Securities Act and the
Exchange Act (at any time after it has become subject to such reporting
requirements); and

                           (c) so long as a Holder owns any Registrable
Securities, to furnish to such Holder forthwith upon request a written statement
by the Company as to its compliance with the reporting requirements of said Rule
144 (at any time after 90 days after the effective date of the first
registration statement filed by the Company for an offering of its securities to
the general public), and of the Securities Act and the Exchange Act (at any time
after it has become subject to such reporting requirements), a copy of the most
recent annual or quarterly report of the Company, and such other reports and
documents so filed by the Company as the Holder may reasonably request in
complying with any rule or regulation of the SEC allowing the Holder to sell any
such securities without registration.

                  1.8 Transfer of Registration Rights. Holders' rights to cause
the Company to register their securities and keep information available, granted
to them by the Company under subsections 1.2 and 1.7 may be assigned to a
transferee or assignee of a Holder's Registrable

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Securities not sold to the public, provided, that the Company is given written
notice by such Holder at the time of or within a reasonable time after said
transfer, stating the name and address of said transferee or assignee and
identifying the securities with respect to which such registration rights are
being assigned. The Company may prohibit the transfer of any Holders' rights
under this subsection 1.8 to any proposed transferee or assignee who the Company
reasonably believes is a competitor of the Company.

         2.   General.

                  2.1 Waivers and Amendments. With the written consent of the
record or beneficial holders of at least a majority of the Registrable
Securities, the obligations of the Company and the rights of the Holders of the
Registrable Securities under this agreement may be waived (either generally or
in a particular instance, either retroactively or prospectively, and either for
a specified period of time or indefinitely), and with the same consent the
Company, when authorized by resolution of its Board of Directors, may enter into
a supplementary agreement for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of this Agreement;
provided, however, that no such modification, amendment or waiver shall reduce
the aforesaid percentage of Registrable Securities. Upon the effectuation of
each such waiver, consent, agreement of amendment or modification, the Company
shall promptly give written notice thereof to the record holders of the
Registrable Securities who have not previously consented thereto in writing.
This Agreement or any provision hereof may be changed, waived, discharged or
terminated only by a statement in writing signed by the party against which
enforcement of the change, waiver, discharge or termination is sought, except to
the extent provided in this subsection 2.1.

                  2.2 Governing Law. This Agreement shall be governed in all
respects by the laws of the State of California as such laws are applied to
agreements between California residents entered into and to be performed
entirely within California.

                  2.3 Successors and Assigns. Except as otherwise expressly
provided herein, the provisions hereof shall inure to the benefit of, and be
binding upon, the successors, assigns, heirs, executors and administrators of
the parties hereto.

                  2.4 Entire Agreement. Except as set forth below, this
Agreement and the other documents delivered pursuant hereto constitute the full
and entire understanding and agreement between the parties with regard to the
subjects hereof and thereof.

                  2.5 Notices. etc. All notices and other communications
required or permitted hereunder shall be in writing and shall be mailed by first
class mail, postage prepaid, certified or registered mail, return receipt
requested, addressed (a) if to Holder, at such Holder's address as set forth
below, or at such other address as such Holder shall have furnished to the
Company in writing, or (b) if to the Company, at the Company's address set forth
below, or at such other address as the Company shall have furnished to the
Holder in writing.

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                  2.6 Severability. In case any provision of this Agreement
shall be invalid, illegal, or unenforceable, the validity, legality and
enforceability of the remaining provisions of this Agreement or any provision of
the other Agreements shall not in any way be affected or impaired thereby.

                  2.7 Titles and Subtitles. The titles of the sections and
subsections of this Agreement are for convenience of reference only and are not
to be considered in construing this Agreement.

                  2.8 Counterparts. This Agreement may be executed in any number
of counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

SVB                                       COMPANY
SILICON VALLEY BANK                       I-FLOW CORPORATION
By: ______________________                By: _______________________
Name: Gary Reagan                         Name: Donald M. Earhart
                (Print)                                         (Print)
Title: Vice President                     Title: Chairman of the Board
                                            President or Vice President
Address: 3003 Tasman Drive                Address: 20202 Windrow Drive
         Santa Clara, California 95054             Lake Forest,
         Attention: Treasury Department            California 92630
                                                   Attn: Chief Financial
                                                   Officer

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