IDEC PHARMACEUTICALS CORP / DE
EXHIBIT 10.10
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<DESCRIPTION>EXHIBIT 10.10
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<P ALIGN="RIGHT"><FONT SIZE=2><A
NAME="kc1823_exhibit_10.10"> </A>
<A NAME="toc_kc1823_1"> </A>
<BR></FONT><FONT SIZE=2><B>Exhibit&nbsp;10.10    <BR>  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="kc1823_idec_pharmaceuticals_corporati__ide03417"> </A>
<A NAME="toc_kc1823_2"> </A>
<BR></FONT><FONT SIZE=2><B>IDEC PHARMACEUTICALS CORPORATION<BR>  </B></FONT><FONT SIZE=2><B><I>1988 STOCK OPTION PLAN    <BR>    <BR>    </I></B></FONT><FONT SIZE=2><B>(Amended and Restated Through October&nbsp;21, 2002)    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>I.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;PURPOSES OF THE PLAN</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;This
Stock Option Plan (the "Plan") is intended to promote the interests of IDEC Pharmaceuticals Corporation, a Delaware corporation (the "Corporation"), by providing a
method whereby key employees (including officers) of the Corporation (or its parent or subsidiary corporations) responsible for the management, growth and financial success of the Corporation (or its
parent or subsidiary corporations) may be offered incentives and rewards which will encourage them to acquire a proprietary interest, or otherwise increase their proprietary interest, in the
Corporation and continue to render services to the Corporation (or its parent or subsidiary corporations). </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;The
following provisions shall be applicable in determining the parent and subsidiary corporations of the Corporation: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;Any
corporation (other than the Corporation) in an unbroken chain of corporations ending with the Corporation shall be considered to be a </FONT> <FONT SIZE=2><B>parent</B></FONT><FONT SIZE=2> corporation of the Corporation, provided each such
corporation in the unbroken chain (other than the Corporation) owns, at the time of the
determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;Each
corporation (other than the Corporation) in an unbroken chain of corporations beginning with the Corporation shall be considered to be a </FONT> <FONT SIZE=2><B>subsidiary</B></FONT><FONT SIZE=2> of the Corporation, provided each such corporation
(other than the last corporation) in the unbroken chain owns, at the time of the
determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>II.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;ADMINISTRATION OF THE PLAN</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;The
Corporation's Board of Directors (the "Board") shall appoint a committee ("Committee") of two (2)&nbsp;or more non-employee Board members to assume
full responsibility for the administration of the Plan. Members of the Committee shall serve for such period of time as the Board may determine and shall be subject to removal by the Board at any
time. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;The
Committee as Plan Administrator shall have full power and authority (subject to the express provisions of the Plan) to establish such rules and regulations as it may
deem appropriate for the proper administration of the Plan and to make such determinations under, and issue such interpretations of, the Plan and any outstanding option grants or stock issuances as it
may deem necessary or advisable. Decisions of the Plan Administrator shall be final and binding on all parties who have an interest in the Plan or any outstanding option or stock issuance thereunder. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>III.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;ELIGIBILITY FOR OPTION GRANTS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;The
persons eligible to receive option grants under the Plan shall be limited tokey employees (including officers) of the Corporation (or its parent or subsidiary
corporations) who render services which contribute to the success and growth of the Corporation (or its parent or subsidiary corporations) or which may reasonably be anticipated to contribute to the
future success and growth of the Corporation (or its parent or subsidiary corporations). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;The
Plan Administrator shall have full authority to determine which eligible individuals are to receive option grants under the Plan, the number of shares to be covered
by each such grant, whether the granted option is to be an incentive stock option ("Incentive Option") which satisfies the requirements of Section&nbsp;422 of the Internal Revenue Code or a
non-statutory option </FONT></P>

</UL>
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not intended to meet such requirements, the time or times at which each such option is to become exercisable, and the maximum term for which the option is to be outstanding. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>IV.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;STOCK SUBJECT TO THE PLAN</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;The
stock issuable under the Plan shall be shares of the Corporation's authorized but unissued or reacquired Common Stock. The maximum number of shares which may be
issued under the Plan shall not exceed 58,580,000 shares.<SUP>*</SUP> The total number of shares issuable under the Plan shall be subject to adjustment from time to time in accordance with
Section&nbsp;IV.(d) of the Plan. </FONT></P>

</UL>
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<DT style='margin-bottom:-11pt;'><FONT SIZE=2><SUP>*</SUP></FONT></DT><DD><FONT SIZE=2>Adjusted
to reflect (i)&nbsp;the 1 for 2.5 reverse Common Stock split effected by the Company on August&nbsp;18, 1991, a 2 for 1 stock split effected by the
Corporation on December&nbsp;21, 1999 and a 3 for 1 stock split effected in the form of a stock dividend on January&nbsp;17, 2001, (ii)&nbsp;the 4,020,000 share increase authorized by the Board
on March&nbsp;18, 1992 and approved by the stockholders at the 1992 Annual Meeting, (iii)&nbsp;the 4,200,000 share increase authorized by the Board on January&nbsp;13, 1993 and approved by the
stockholders at the 1993 Annual Meeting, (iv)&nbsp;the 3,900,000 share increase authorized by the Board on February&nbsp;28, 1994 and approved by the stockholders at the 1994 Annual Meeting,
(v)&nbsp;the 3,000,000 share increase authorized by the Board on January&nbsp;25, 1995, and approved by the stockholders at the 1995 Annual Meeting, (vi)&nbsp;the 7,200,000 share increase
authorized by the Board on January&nbsp;24, 1996, and approved by the stockholders at the 1996 Annual Meeting, (vii)&nbsp;the 4,800,000 share increase authorized by the Board on
February&nbsp;24, 1997, and approved by the stockholders at the 1997 Annual Meeting, (viii)&nbsp;the 5,130,000 share increase authorized by the Board on February&nbsp;20, 1998, approved by the
stockholders at the 1998 Annual Meeting, (ix)&nbsp;the 4,800,000 share increase authorized by the Board on January&nbsp;13, 1999, approved by the stockholders at the 1999 Annual Meeting,
(x)&nbsp;the 5,130,000 share increase authorized by the Board on January&nbsp;12, 2000, approval at the 2000 Annual Meeting, (xi)&nbsp;the 5,640,000 share increase authorized by the Board on
January&nbsp;16, 2001, approved by the stockholders at the 2001 Annual Meeting, and (xii)&nbsp;the 5,000,000 share increase authorized by the Board on January&nbsp;23, 2002, subject to
stockholder approval at the 2002 Annual Meeting. In no event, however, shall more than 30,707,067 shares of Common Stock be issued under the Plan after February&nbsp;28, 2002, inclusive of the
5,000,000 share increase for which stockholder approval is sought at the 2002 Annual Meeting, subject to adjustment under Section&nbsp;IV(d)&nbsp;in the event of changes in the Corporation's
capital structure. </FONT></DD></DL>
<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;In
no event may the aggregate number of shares of Common Stock for which any one individual participating in the Plan may be granted stock options and separately
exercisable stock appreciation rights exceed 7,500,000 shares in the aggregate over the remaining term of the Plan, subject to adjustment from time to time in accordance with Section&nbsp;IV.(d) of
the Plan. For purposes of such limitation, no stock options or stock appreciation rights granted prior to January&nbsp;1, 1994 shall be taken into account. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;Should
an option expire or terminate for any reason prior to exercise in full, the shares subject to the portion of the option not so exercised shall be available for
subsequent option grants under the Plan. Unvested shares issued under the Plan and subsequently repurchased by the Corporation, at the option exercise price paid per share, pursuant to the
Corporation's repurchase rights under the Plan, shall be added back to the number of shares of Common Stock reserved for issuance under the Plan and shall accordingly be available for reissuance
through one or more subsequent option grants under the Plan. Shares subject to any option cancelled in accordance with Section&nbsp;VIII of the Plan shall
reduce on a share-for-share basis the number of shares of Common Stock available for subsequent option grants under this Plan. In addition, should the exercise price of an
outstanding option under the Plan be paid with shares of Common Stock, then the number of shares of Common Stock available for issuance under the Plan shall be reduced by the gross </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

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number of shares for which the option is exercised, and not by the net number of shares of Common Stock actually issued to the option holder. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;In
the event any change is made to the Common Stock issuable under the Plan by reason of any stock split, stock dividend, combination of shares, exchange of shares or
other change affecting the outstanding Common Stock as a class without the Corporation's receipt of consideration, then appropriate adjustments shall be made to (I)&nbsp;the maximum number and/or
class of securities issuable under the Plan, (II)&nbsp;the maximum number and/or class of securities for which stock options and separately exercisable stock appreciation rights may be granted to
any one participant in the aggregate after December&nbsp;31, 1993 and (III)&nbsp;the number and/or class of securities and exercise price per share in effect under each outstanding option in order
to prevent the dilution or enlargement of benefits thereunder. The adjustments determined by the Plan Administrator shall be final, binding and conclusive. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;V.</FONT><FONT
SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;TERMS AND CONDITIONS OF OPTIONS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Options granted pursuant to the Plan shall be
authorized by action of the Plan Administrator and may, at the Plan Administrator's discretion, be either Incentive Options or non-statutory options. Each granted option shall be evidenced
by one or more instruments in the form approved by the Plan Administrator; </FONT><FONT SIZE=2><I>provided</I></FONT><FONT SIZE=2>, however, that each such instrument shall comply with the terms and
conditions specified below. Each instrument evidencing an Incentive Option shall, in addition, be subject to the applicable provisions of Section&nbsp;VI. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Option Price.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;A.&nbsp;&nbsp;&nbsp;&nbsp;The
option price per share shall be fixed by the Plan Administrator, but in no event shall the option price per share be less than one hundred percent (100%) of the fair
market value of a share of Common Stock on the date of the option grant. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;B.&nbsp;&nbsp;&nbsp;&nbsp;The
option price shall become immediately due upon exercise of the option and shall, subject to the provisions of Section&nbsp;IX and the instrument evidencing the
grant, be payable in one of the alternative forms specified below: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;full
payment in cash or check payable to the Corporation; or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;full
payment in shares of Common Stock held by the optionee for the requisite period necessary to avoid a charge to the Corporation's reported earnings and valued at
fair market value on the Exercise Date (as such term is defined below); or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;full
payment through a combination of shares of Common Stock held by the optionee for the requisite period necessary to avoid a charge to the Corporation's reported
earnings and valued at fair market value on the Exercise Date and cash or check payable to the Corporation; or </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv)&nbsp;&nbsp;full
payment effected through a broker-dealer sale and remittance procedure pursuant to which the optionee shall provide irrevocable instructions (I)&nbsp;to a
Corporation-designated brokerage firm to (A)&nbsp;effect the immediate sale of a sufficient number of the purchased shares to enable such firm to remit to the Corporation, out of the sale proceeds
available on the settlement date, sufficient funds to cover the aggregate option price payable for the purchased shares plus all applicable Federal and State income and employment taxes required to be
withheld by the Corporation in connection with such purchase and (B)&nbsp;remit those funds to the Corporation on the settlement date, and (II)&nbsp;to the Corporation to deliver the certificates
for the purchased shares directly to such brokerage firm. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;For
purposes of this subparagraph&nbsp;B, the Exercise Date shall be the date on which written or electronic notice of the option exercise is received by the Corporation. Except to the
extent the sale and remittance procedure is utilized in connection with the exercise of the option, payment of the option price for the purchased shares must accompany such notice. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.&nbsp;&nbsp;&nbsp;&nbsp;The
fair market value per share of Common Stock on any relevant date under subparagraph&nbsp;A or B (and for all other valuation purposes under the Plan) shall be
determined in accordance with the following provisions: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;If
the Common Stock is not at the time listed or admitted to trading on any national stock exchange but is traded on The Nasdaq Stock Market, the fair market value
shall be the closing selling price per share of Common Stock on the date in question, as reported by the National Association of Securities Dealers on The Nasdaq Stock Market and published in </FONT> <FONT SIZE=2><I>The Wall Street
Journal</I></FONT><FONT SIZE=2>. If there is no reported closing selling price for the Common Stock on the date in question, then the closing selling price on
the last preceding date for which such quotation exists shall be determinative of fair market value. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;If
the Common Stock is at the time listed or admitted to trading on any national stock exchange, then the fair market value shall be the closing selling price per share
of Common Stock on the date in question on the stock exchange determined by the Plan Administrator to be the primary market for the Common Stock, as such price is officially quoted in the composite
tape of transactions on such exchange and published in </FONT><FONT SIZE=2><I>The Wall Street Journal</I></FONT><FONT SIZE=2>. If there is no reported sale of Common Stock on
such exchange on the date in question, then the fair market value shall be the closing selling price on the exchange on the last preceding date for which such quotation exists. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Term and Exercise of Options.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Each option granted under the Plan shall be exercisable at such time or times,
during such period, and for such number of shares as shall be determined by the Plan Administrator and set forth in the instrument evidencing such option; </FONT> <FONT SIZE=2><I>provided</I></FONT><FONT SIZE=2>, however, that no such option shall
have a term in excess of ten (10)&nbsp;years from the grant date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Limited Transferability of Options.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;During the lifetime of the optionee, Incentive Options shall be
exercisable only by the optionee and shall not be assignable or transferable other than by will or by the laws of descent and distribution following the optionee's death. However,
non-statutory options may, in connection with the optionee's estate plan, be assigned in whole or in part during the optionee's lifetime to one or more members of the optionee's immediate
family or to a trust established exclusively for one or more such family members. The assigned portion may only be exercised by the person or persons who acquire a proprietary interest in the option
pursuant to the assignment. The terms applicable to the assigned portion shall be the same as those in effect for the option immediately prior to such assignment and shall be set forth in such
documents issued to the assignee as the Plan Administrator may deem appropriate. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Effect of Termination of Service.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;A.&nbsp;&nbsp;&nbsp;&nbsp;Should
an optionee cease to remain in Service (as defined in subparagraph&nbsp;D below) for any reason (including death or permanent disability as defined in
Section&nbsp;22(e)(3) of the Internal Revenue Code) while the holder of one or more outstanding options granted to such optionee under the Plan, then such option or options shall not (except to the
extent otherwise provided pursuant to Section&nbsp;X below) remain exercisable for more than a thirty-six (36)-month period (or such shorter period determined by the Plan Administrator
and specified in the instrument evidencing the grant) following the date of such cessation of Service. Under no circumstances, however, shall any such option be exercisable after the specified
expiration date of the option term. Each such option shall, during such thirty-six (36)-month or shorter period, be exercisable only to the extent of the number of shares (if any) for
which the option is exercisable on the date of the optionee's cessation of Service. Upon the expiration of such thirty-six (36)-month or shorter period or (if earlier) upon the expiration
of the option term, the option shall terminate and cease to be exercisable. However, the option shall, immediately upon the optionee's cessation of Service for any reason, terminate and cease to be
outstanding for any option shares for which the option is not otherwise at that time exercisable. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>4</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;B.&nbsp;&nbsp;&nbsp;&nbsp;Any
outstanding option held by the optionee and exercisable in whole or in part on the date of his or her death may be subsequently exercised, but only to the extent of
the number of shares (if any) for which the option is exercisable on the date of the optionee's cessation of Service (less any option shares subsequently purchased by the optionee prior to death), by
the personal representative of the
optionee's estate or by the person or persons to whom the option is transferred pursuant to the optionee's will or in accordance with the laws of descent and distribution. The right to exercise the
option for those shares shall terminate upon the </FONT><FONT SIZE=2><I>earlier </I></FONT><FONT SIZE=2>of (i)&nbsp;the third anniversary of the date of the optionee's cessation of Service or
(ii)&nbsp;the specified expiration date of the option term. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding
subparagraphs&nbsp;A and B above, the Plan Administrator shall have complete discretion, exercisable either at the time the option is granted or at any
time while the option remains outstanding, to permit one or more options held by the optionee under the Plan to be exercised, during the limited period of exercisability provided under
Section&nbsp;V.4.A above, not only with respect to the number of shares for which each such option is exercisable at the time of the optionee's cessation of Service but also with respect to one or
more subsequent installments for which the option would otherwise have become exercisable had such cessation of Service not occurred. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.&nbsp;&nbsp;&nbsp;&nbsp;For
purposes of the foregoing provisions of this Section&nbsp;V.4 (and all other provisions of the Plan), the optionee shall be deemed to remain in the Service of the
Corporation for so long as such individual renders services on a periodic basis to the Corporation or any parent or subsidiary corporation in the capacity of an Employee, a non-employee
member of the board of directors or an independent consultant or advisor, unless the option agreement evidencing the option grant and/or the purchase agreement evidencing the purchased option shares
specifically provides otherwise. The optionee shall be considered to be an Employee for so long as such individual remains in the employ of the Corporation or one or more of its parent or subsidiary
corporations, subject to the control and direction of the employer entity as to the work to be performed and as to the manner and method of performance. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Stockholder Rights.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;An optionee shall have none of the rights of a stockholder with respect to any shares
covered by the option until such individual shall have exercised the option and paid the option price for the purchased shares. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Repurchase Rights.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Unvested shares of Common Stock may be issued under the Plan which are subject to
repurchase by the Corporation in accordance with the following provisions: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;Upon
the optionee's cessation of Service while holding unvested shares under the Plan, the Corporation shall have the right to repurchase any or all of those unvested
shares at the option price paid per share. The terms and conditions upon which such repurchase right shall be exercisable (including the period and procedure for exercise and the appropriate vesting
schedule for the purchased shares) shall be established by the Plan Administrator and set forth in the instrument evidencing such repurchase right. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;All
of the Corporation's outstanding repurchase rights shall automatically terminate, and all shares subject to such terminated rights shall immediately vest in full,
upon the occurrence of any Corporate Transaction under Section&nbsp;VII of this Plan, except to the extent: (i)&nbsp;any such repurchase right is to be assigned to the successor corporation (or
parent thereof) in connection with the Corporate Transaction
or (ii)&nbsp;such accelerated vesting is precluded by other limitations imposed by the Plan Administrator at the time the repurchase right is issued. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;The
Plan Administrator shall have the discretionary authority, exercisable either before or after the optionee's cessation of Service, to cancel the Corporation's
outstanding repurchase rights </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>5</FONT></P>

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with respect to any or all unvested shares purchased or purchasable by the optionee under the Plan and thereby accelerate the vesting of those shares in whole or in part at any time. </FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>VI.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;INCENTIVE OPTIONS.</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
terms and conditions specified below shall be applicable to all Incentive Options granted under the Plan. Incentive Options may only be granted to individuals who are Employees.
Options which are specifically designated as "non-statutory" options when issued under the Plan shall </FONT><FONT SIZE=2><I>not </I></FONT><FONT SIZE=2>be subject to such terms and
conditions. </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Dollar Limitation.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The aggregate fair market value (determined as of the respective date or dates of grant)
of the Common Stock for which one or more options granted to any Employee under this Plan (or any other option plan of the Corporation or its parent or subsidiary corporations) may for the first time
become exercisable as incentive stock options under the Federal tax laws during any one calendar year shall not exceed the sum of One Hundred Thousand Dollars ($100,000). To the extent the Employee
holds two or more such options which become exercisable for the first time in the same calendar year, the foregoing limitation on the exercisability of such options as incentive stock options under
the Federal tax laws shall be applied on the basis of the order in which such options are granted. Should the number of shares of Common Stock for which an Incentive Option first becomes exercisable
in any calendar year exceed the applicable One Hundred Thousand Dollar ($100,000) limitation, the option may nevertheless be exercised for those excess shares in such calendar year as a
non-statutory option. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;10% Stockholder.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;If any individual to whom the Incentive Option is granted is the owner of stock (as
determined under Section&nbsp;424(d) of the Internal Revenue Code) possessing ten percent (10%) or more of the total combined voting power of all classes of stock of the Corporation or any one of
its parent or subsidiary corporations, then the option price per share shall not be less than one hundred and ten percent (110%) of the fair market value per share of Common Stock on the grant date,
and the option term shall not exceed five (5)&nbsp;years, measured from such grant date. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Except
as modified by the preceding provisions of this Section&nbsp;VI, all the provisions of the Plan shall be applicable to the Incentive Options granted hereunder. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>VII.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;CORPORATE TRANSACTION/CHANGE IN CONTROL</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;In
the event of any of the following transactions (a "Corporate Transaction"): </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;a
merger or consolidation in which the Corporation is not the surviving entity, except for a transaction the principal purpose of which is to change the State of the
Corporation's incorporation, </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;the
sale, transfer or other disposition of all or substantially all of the assets of the Corporation in liquidation or dissolution of the Corporation, or </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;any
reverse merger in which the Corporation is the surviving entity but in which fifty percent (50%) or more of the Corporation's outstanding voting stock is
transferred to persons different from those who held the stock immediately prior to such merger, </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;each
outstanding option under the Plan shall automatically accelerate so that each such option shall, immediately prior to the specified effective date for the Corporate Transaction,
become exercisable for the total number of shares of Common Stock at the time subject to such option and may be exercised for all or any portion of those shares as fully-vested shares of Common Stock.
However, an outstanding option under the Plan shall not so accelerate if and to the extent: (i)&nbsp;such option is, in connection with the Corporate Transaction, either to be assumed by the
successor corporation or parent thereof or be replaced with a comparable option to purchase shares of the capital stock of the successor corporation or parent thereof or (ii)&nbsp;the acceleration
of </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>6</FONT></P>

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<P><FONT SIZE=2>
such option is subject to other applicable limitations imposed by the Plan Administrator at the time of grant. The determination of comparability under clause&nbsp;(i) above shall be made by the
Plan Administrator and its determination shall be final, binding and conclusive. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;Each
outstanding option under the Plan which is assumed in connection with the Corporate Transaction or is otherwise to continue in effect shall be appropriately
adjusted, immediately after such Corporate Transaction, to apply and pertain to the number and class of securities which would have been issued, in consummation of such Corporate Transaction, to an
actual holder of the same number of shares of Common Stock as are subject to such option immediately prior to such Corporate Transaction. Appropriate adjustments shall also be made to the option price
payable per share, provided the aggregate option price payable for such securities shall remain the same. In addition, the class and number of securities available for issuance under the Plan on both
an aggregate and per participant basis shall be appropriately adjusted to reflect the effect of the Corporate Transaction upon the Corporation's capital structure. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;In
connection with any Change in Control (as defined below), the Plan Administrator shall have full power and authority, exercisable either at the time the option is
granted or at any time while the option remains outstanding, to provide for the automatic acceleration of each outstanding option under the Plan so that each such option shall, immediately prior to
the effective date of the Change in Control, become exercisable for the total number of shares at the time subject to such option and may be exercised for all or any portion of those shares as
fully-vested shares of Common Stock. The Plan Administrator shall also have full power and authority to condition such option acceleration, and the termination of any of the Corporation's repurchase
rights with respect to any unvested shares purchased or purchasable under the Plan, upon the subsequent termination of the optionee's Service within a designated period following the Change in
Control. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;A
</FONT><FONT SIZE=2><B>Change in Control</B></FONT><FONT SIZE=2> shall be deemed to occur in the event: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;twenty-five
percent (25%) or more of the Corporation's outstanding voting stock is acquired pursuant to a tender or exchange offer (A)&nbsp;which is made
directly to the Corporation's stockholders by any person or related group of persons (other than the Corporation or a person that directly or indirectly controls, is controlled by or is under common
control with, the Corporation) and (B)&nbsp;which the Board does not recommend the stockholders to accept; or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;there
is a change in the composition of the Board over a period of twenty-four (24)&nbsp;consecutive months or less such that a majority of the Board
members ceases, by reason of one or more proxy contests for the election of Board members, to be comprised of individuals who either (A)&nbsp;have been Board members continuously since the beginning
of such period or (B)&nbsp;have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause&nbsp;(A) who were still
in office at the time such election or nomination was approved by the Board. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;Immediately
following the consummation of a Corporate Transaction, all outstanding options under the Plan shall terminate and cease to be outstanding, except to the
extent assumed by the successor corporation or its parent company. Upon a Change in Control, each outstanding option accelerated pursuant to subsection&nbsp;VII.(c) above shall remain fully
exercisable until the expiration or sooner termination of the option term specified in the agreement evidencing such grant. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;The
exercisability as incentive stock options under the Federal tax laws of any options accelerated in connection with a Corporate Transaction or Change in Control shall
remain subject to the dollar limitation of Section&nbsp;VI.(a) of the Plan. To the extent such dollar limitation is </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>7</FONT></P>

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<P><FONT SIZE=2>
exceeded, the accelerated option shall be exercisable as a non-statutory option under the Federal tax laws. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;The
grant of options under this Plan shall in no way affect the right of the Corporation to adjust, reclassify, reorganize or otherwise change its capital or business
structure or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>VIII.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;STOCK APPRECIATION RIGHTS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;Provided
and only if the Plan Administrator determines in its discretion to implement the stock appreciation right provisions of this Section&nbsp;VIII, one or more
optionees may be granted the right, exercisable upon such terms and conditions as the Plan Administrator may establish, to surrender all or part of an unexercised option under the Plan in exchange for
a distribution from the Corporation in an amount equal to the excess of (i)&nbsp;the fair market value (on the option surrender date) of the number of shares in which the optionee is at the time
vested under the surrendered option (or surrendered portion thereof) over (ii)&nbsp;the aggregate option price payable for such vested shares. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;No
surrender of an option shall be effective hereunder unless it is approved by the Plan Administrator. If the surrender is so approved, then the distribution to which
the optionee shall accordingly become entitled under this Section&nbsp;VIII may be made in shares of Common Stock valued at fair market value on the option surrender date, in cash, or partly in
shares and partly in cash, as the Plan Administrator shall in its sole discretion deem appropriate. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;If
the surrender of an option is rejected by the Plan Administrator, then the optionee shall retain whatever rights the optionee had under the surrendered option (or
surrendered portion thereof) on the option surrender date and may exercise such rights at any time prior to the </FONT><FONT SIZE=2><I>later </I></FONT><FONT SIZE=2>of (i)&nbsp;five
(5)&nbsp;business days after the receipt of the rejection notice or (ii)&nbsp;the last day on which the option is otherwise exercisable in accordance with the terms of the instrument evidencing
such option, but in no event may such rights be exercised more than ten (10)&nbsp;years after the date of the option grant. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;One
or more officers of the Corporation subject to the short-swing profit restrictions of the Federal securities laws may, in the Plan Administrator's sole discretion,
be granted limited stock appreciation rights in tandem with their outstanding options under the Plan. Upon the occurrence of a Hostile Take-Over, each outstanding option with such a
limited stock appreciation right shall automatically be cancelled, to the extent such option is at the time exercisable for fully-vested shares of Common Stock (including any shares which may vest in
connection with such Hostile Take-Over). The optionee shall in return be entitled to a cash distribution from the Corporation in an amount equal to the excess of (i)&nbsp;the
Take-Over Price of the vested shares of Common Stock at the time subject to the cancelled option (or cancelled portion of such option) over (ii)&nbsp;the aggregate exercise price payable
for such shares. The cash distribution payable upon such cancellation shall be made within five (5)&nbsp;days following the consummation of the Hostile Take-Over. The Plan Administrator
shall pre-approve, at the time the limited stock appreciation right is granted, the subsequent exercise of that right in accordance with the terms of the grant and the provisions of this
Section&nbsp;VIII.(d). No additional approval of the Plan Administrator or the Board shall be required at the time of the actual option cancellation and cash distribution. The balance of the option
(if any) shall continue to remain outstanding and exercisable in accordance with the terms and conditions of the instrument evidencing such grant. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;For
purposes of Section&nbsp;VIII.(d), the following definitions shall be in effect: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;A
</FONT><FONT SIZE=2><B>Hostile Take-Over</B></FONT><FONT SIZE=2> shall be deemed to occur in the event any person or related group of persons (other than the Corporation
or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation) directly or indirectly acquires beneficial </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>8</FONT></P>

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<P><FONT SIZE=2>
ownership (within the meaning of Rule&nbsp;13d-3 of the Securities Exchange Act of 1934) of securities possessing more than twenty-five percent (25%) of the total combined
voting power of the Corporation's outstanding securities pursuant to a tender or exchange offer made directly to the Corporation's stockholders which the Board does not recommend such stockholders to
accept. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
</FONT><FONT SIZE=2><B>Take-Over Price</B></FONT><FONT SIZE=2> per share shall be deemed to be equal to the </FONT><FONT SIZE=2><I>greater </I></FONT><FONT SIZE=2>of
(a)&nbsp;the fair market value per share on the date of cancellation, as determined pursuant to the valuation provisions of Section&nbsp;II.1.C, or (b)&nbsp;the highest reported price per share
paid by the acquiring entity in effecting such Hostile Take-Over. However, to the extent the cancelled option is an Incentive Option, the Take-Over Price shall not exceed the
clause&nbsp;(a) price per share. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;The
shares of Common Stock subject to any option surrendered or cancelled for an appreciation distribution pursuant to this Section&nbsp;VIII shall </FONT> <FONT SIZE=2><B>not</B></FONT><FONT SIZE=2> be available for subsequent option grant under the
Plan. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>IX.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;LOANS OR INSTALLMENT PAYMENTS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Plan Administrator may, in its discretion, assist any optionee (other than any executive officer of the Corporation or member of the Board) in the exercise of one or more options
granted to such individual under the Plan, including the satisfaction of any Federal and State income and employment tax obligations arising therefrom, by (i)&nbsp;authorizing the extension of a
loan from the Corporation to such optionee or (ii)&nbsp;permitting the optionee to pay the option price for the purchased Common Stock in installments over a period of years. The terms of any such
loan or installment method of payment (including the interest rate and terms of repayment) will be upon such terms as the Plan Administrator specifies in the applicable option agreement or otherwise
deems appropriate under the circumstances. Loans or installment payments may be granted with or without security or collateral (other than to individuals who are independent consultants or advisors,
in which event the loan must be adequately secured by collateral other than the purchased shares). However, the maximum credit available to the optionee may not exceed the option price of the acquired
shares (less the par value of those shares) plus any Federal and State income and employment withholding taxes to which theoptionee may become subjectin connection with the exercise of the option. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>X.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;EXTENSION OF EXERCISE PERIOD</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Plan Administrator shall have full power and authority, to extend the period of time for which the option is to remain exercisable following the optionee's cessation of Service from
the thirty-six (36)&nbsp;month or shorter period set forth in the option agreement to such greater period of time as the Plan Administrator shall deem appropriate. In no event, however,
shall such option be exercisable after the specified expiration date of the option term. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>XI.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;AMENDMENT OF THE PLAN</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Board shall have complete and exclusive power and authority to amend or modify the Plan in any or all respects whatsoever; </FONT><FONT SIZE=2><I>provided</I></FONT><FONT SIZE=2>,
however, that no such amendment or modification shall, without the consent of the stockholders, adversely affect rights and obligations with respect to options at the time outstanding under the Plan.
In addition, any amendment which increases the number of shares of Common Stock authorized for issuance under the Plan or which materially increases the benefits accruing to individuals participating
in the Plan shall require stockholder approval. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>XII.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;EFFECTIVE DATE AND TERM OF PLAN</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;The
Plan was initially adopted by the Board on July&nbsp;19, 1988 and approved by the Corporation's stockholders on March&nbsp;29, 1989. The Plan was subsequently
amended by the Board on July&nbsp;18, 1990, and such amendment was approved by the Corporation's stockholders in October, 1990. In January&nbsp;1991, the Plan was again amended to increase by
2,880,000 shares the number of shares of Common Stock issuable under the Plan, and such share increase was </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>9</FONT></P>

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<P><FONT SIZE=2>
approved by the Corporation's stockholders on March&nbsp;20, 1991. The Board further amended the Plan on May&nbsp;22, 1991, with such amendments to become effective as of the date the
Corporation's Common Stock first became traded on The Nasdaq Stock Market, in order to revise certain provisions previously required when the Plan was subject to the permit requirements of the
California Corporations Department. On March&nbsp;18, 1992, the Plan was amended and restated in its entirety, including an increase of 4,020,000 shares to the number of shares of Common Stock
issuable thereunder. The 1992 restatement, including the 4,020,000 share increase, was approved by the stockholders at the 1992 Annual Meeting. On January&nbsp;13, 1993, the Board amended the Plan
to increase by an additional 4,200,000 shares the number of shares of Common Stock issuable under the Plan, and such share increase was approved by the stockholders at the 1993 Annual Meeting. On
February&nbsp;28, 1994, the Board amended the Plan to increase by an additional 3,900,000 shares the number of shares of Common Stock issuable under the Plan, and such increase was approved by the
stockholders at the 1994 Annual Meeting. On January&nbsp;25, 1995, the Board amended the Plan to increase by an additional 3,000,000 shares the number of shares of Common Stock issuable under the
Plan, and such increase was approved by the stockholders at the 1995 Annual Meeting. On January&nbsp;24, 1996, the Board adopted an amendment which increased the number of shares of Common Stock
issuable under the Plan by an
additional 7,200,000 shares, and such increase was approved by the stockholders at the 1996 Annual Meeting. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
February&nbsp;24, 1997, the Board adopted a series of amendments to the Plan (the "1997 Amendments") which (i)&nbsp;increased the number of shares of Common Stock reserved for
issuance over the term of the Plan by an additional 4,800,000 shares, (ii)&nbsp;rendered non-employee Board members serving as Plan Administrator eligible to receive option grants under
the Plan, (iii)&nbsp;allowed unvested shares issued under the Plan and subsequently repurchased by the Corporation at the option exercise price paid per share to be reissued under the Plan,
(iv)&nbsp;removed certain restrictions on the eligibility of non-employee Board members to serve as Plan Administrator, (v)&nbsp;extended the term of the Option Plan from
July&nbsp;19, 1998 to December&nbsp;31, 2002 and (vi)&nbsp;effected a series of additional changes to the provisions of the Plan (including the stockholder approval requirements, the
transferability of non-statutory stock options and the elimination of the six (6)-month holding period requirement as a condition to the exercise of stock appreciation rights) in order to
take advantage of the recent amendments to Rule&nbsp;16b-3 of the 1934 Act which exempts certain officer and director transactions under the Plan from the short-swing liability
provisions of the Federal securities laws. The 1997 Amendments were approved by the Corporation's stockholders at the 1997 Annual Meeting. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
February&nbsp;20, 1998, the Board authorized an increase of 5,130,000 shares of Common Stock to the share reserve under the Plan, and the stockholders approved such increase at the
1998 Annual Meeting. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
January&nbsp;13, 1999, the Board authorized an increase of 4,800,000 shares of Common Stock to the share reserve under the Plan, and the stockholders approved such increase at the
1999 Annual Meeting. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
January&nbsp;12, 2000, the Board adopted a series of amendments to the Plan (the "2000 Amendments") which (i)&nbsp;increased the number of shares of Common Stock reserved for
issuance over the term of the Plan by an additional 5,130,000 shares; (ii)&nbsp;extend the term of the Option Plan from December&nbsp;31, 2002 to December&nbsp;31, 2005; (iii)&nbsp;required
the option price per share of Common Stock subject to each option granted under the Option Plan to be not less than 100% of the fair market value per share of Common Stock on the date of grant;
(iv)&nbsp;removed the non-employee Board members and all independent consultants from the class of persons eligible to receive option grants under the Option Plan; and
(v)&nbsp;required the Plan Administrator to be a committee comprised only of non-employee Board members. The 2000 Amendments were approved by the Corporation's stockholders at the 2000
Annual Meeting. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>10</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
May&nbsp;17, 2000, the Board further amended the Plan to eliminate the Plan Administrator's authority to effect the cancellation and regrant of options under the Plan. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
January&nbsp;16, 2001, the Board authorized an increase of 5,640,000 shares of Common Stock to the share reserve under the Plan, and the stockholders approved such increase at the
2001 Annual Meeting. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
January&nbsp;23, 2002, the Board authorized an increase of 5,000,000 shares of Common Stock to the share reserve under the Plan. No options granted on the basis of the 5,000,000
share increase shall vest or become exercisable unless and until such share increase is approved by the stockholders at the 2002 Annual Meeting. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On
October&nbsp;21, 2002, the Board amended the Plan to (i)&nbsp;require stockholder approval of any amendments which increase the number of shares of Common Stock authorized for
issuance under the Plan or which materially increase the benefits accruing to individuals participating in the Plan and (ii)&nbsp;eliminate the authority of the Plan Administrator to make loans
under the Plan to executive officers of the Corporation or Board members. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;The
provisions of the 1992 restatement and of each subsequent amendment to the Plan shall apply only to stock options and stock appreciation rights granted under the
Plan from and after the applicable effective date of such restatement or amendment. All stock options and stock appreciation rights issued and outstanding under the Plan immediately prior to each such
effective date shall continue to be governed by the terms and conditions of the Plan (and the respective agreements evidencing each such option or stock appreciation right) as in effect on the date
each such option or stock appreciation right was previously granted, and nothing in the 1992 restatement or in any subsequent amendment shall be deemed to affect or otherwise modify the rights or
obligations of the holders of such prior options or stock appreciation rights with respect to their acquisition of shares of Common Stock under such options or their exercise of such stock
appreciation rights. However, the Plan Administrator may, in its discretion, modify stock option or stock appreciation right issued and outstanding immediately prior to the effective date of the 1992
restatement or any subsequent amendment to include one or more provisions to the Plan added by such restatement or amendment. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;Unless
sooner terminated in accordance with Section&nbsp;VII, the Plan shall terminate upon the </FONT><FONT SIZE=2><I>earlier </I></FONT><FONT SIZE=2>of
(i)&nbsp;December&nbsp;31, 2005 or (ii)&nbsp;the date on which all shares available for issuance under the Plan shall have been issued or cancelled pursuant to the exercise, surrender of
cash-out of the stock options and stock appreciation rights granted hereunder. If the date of termination is determined under clause&nbsp;(i) above, then each stock option or stock
appreciation right outstanding on such date shall thereafter continue to have force and effect in accordance with the provisions of the instruments evidencing such grant. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;Options
may be granted under this Plan to purchase shares of Common Stock in excess of the number of shares then available for issuance under the Plan, provided any
excess shares actually issued under the Plan are held in escrow until stockholder approval is obtained for a sufficient increase in the number of shares available for issuance under the Plan. If such
stockholder approval is not obtained within twelve (12)&nbsp;months after the date the first such excess option grants are made, then (I)&nbsp;any unexercised excess options shall terminate and
cease to be exercisable and (II)&nbsp;the Corporation shall promptly refund the purchase price paid for any excess shares actually issued under the Plan and held
in escrow, together with interest (at the applicable Short Term Federal Rate) for the period the shares were held in escrow. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>XIII.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;USE OF PROCEEDS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Any
cash proceeds received by the Corporation from the sale of shares pursuant to options granted under the Plan shall be used for general corporate purposes. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>11</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>XIV.</B></FONT><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;REGULATORY APPROVALS</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
implementation of the Plan, the granting of any stock option or stock appreciation right hereunder, and the issuance of stock upon the exercise of any such option or stock
appreciation right shall be subject to the procurement by the Corporation of all approvals and permits required by regulatory authorities having jurisdiction over the Plan, the options and stock
appreciation rights granted under it and the stock issued pursuant to it. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>12</FONT></P>

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<P><br><A NAME="02SAN1823_2">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_kc1823_1">Exhibit 10.10</A></FONT><BR>
</UL>
<FONT SIZE=2><A HREF="#toc_kc1823_2">IDEC PHARMACEUTICALS CORPORATION 1988 STOCK OPTION PLAN (Amended and Restated Through October 21, 2002)</A></FONT><BR>

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