NON-QUALIFIED STOCK OPTION AGREEMENT ARCHEMIX CORP

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EXHIBIT 10.24

FOR GRANTS TO SENIOR EXECUTIVES AND DIRECTORS

[APPROVED BY THE BOARD OF DIRECTORS 1/05]

NON-QUALIFIED STOCK OPTION AGREEMENT

ARCHEMIX CORP.

AGREEMENT made as of the ___ day of _______ 200_, between Archemix Corp.

(the "Company"), a Delaware corporation having a principal place of business in

Cambridge, Massachusetts, and _______________ of ___________ (the

"Participant").

WHEREAS, the Company desires to grant to the Participant an Option to

purchase shares of its common stock, $.001 par value per share (the "Shares"),

under and for the purposes set forth in the Company's 2001 Employee, Director

and Consultant Stock Plan (the "Plan");

WHEREAS, the Company and the Participant understand and agree that any

terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Participant each intend that the Option

granted herein shall be a Non-Qualified Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set

forth and for other good and valuable consideration, the parties hereto agree as

follows:

1. GRANT OF OPTION.

The Company hereby grants to the Participant the right and option to

purchase all or any part of an aggregate of _______________ Shares, on the terms

and conditions and subject to all the limitations set forth herein, under United

States securities and tax laws, and in the Plan, which is incorporated herein by

reference. The Participant acknowledges receipt of a copy of the Plan.

2. PURCHASE PRICE.

The purchase price of the Shares covered by the Option shall be $_____ per

Share, subject to adjustment, as provided in the Plan, in the event of a stock

split, reverse stock split or other events affecting the holders of Shares after

the date hereof (the "Purchase Price"). Payment shall be made in accordance with

Paragraph 8 of the Plan.

3. EXERCISABILITY OF OPTION.

Subject to the terms and conditions set forth in this Agreement and the

Plan, the Option granted hereby shall become exercisable as follows:

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On the first anniversary of the date up to _________ Shares

of this Agreement

Every three months thereafter until an additional _________ Shares

the fourth anniversary of this

Agreement.

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Alternatively, at the election of the Participant, the Option may be

exercised in whole or in part at any time as to Shares which have not yet vested

in accordance with the above schedule; provided however, as a condition to

exercising the Option for such unvested Shares, the Participant shall execute a

Restricted Stock Agreement in the form attached hereto as Exhibit C.

The foregoing rights are cumulative and are subject to the other terms and

conditions of this Agreement and the Plan.

4. TERM OF OPTION.

The Option shall terminate ten years from the date of this Agreement, but

shall be subject to earlier termination as provided herein or in the Plan.

If the Participant ceases to be an employee, director or consultant of the

Company or of an Affiliate (for any reason other than the death or Disability of

the Participant or termination of the Participant for "cause" as defined in the

Plan), the Option may be exercised, if it has not previously terminated, within

three months after the date the Participant ceases to be an employee, director

or consultant of the Company or an Affiliate, or within the originally

prescribed term of the Option, whichever is earlier, but may not be exercised

thereafter. In such event, the Option shall be exercisable only to the extent

that the Option has become exercisable and is in effect at the date of such

cessation of employment, directorship or consultancy.

Notwithstanding the foregoing, in the event of the Participant's Disability

or death within three months after the termination of employment, directorship

or consultancy, the Participant or the Participant's Survivors may exercise the

Option within one year after the date of the Participant's termination of

employment, directorship or consultancy, but in no event after the date of

expiration of the term of the Option.

In the event the Participant's employment, directorship or consultancy is

terminated by the Company or an Affiliate for "cause" as defined in the Plan,

the Participant's right to exercise any unexercised portion of this Option shall

cease immediately as of the time the Participant is notified his or her

employment, directorship or consultancy is terminated for "cause", and this

Option shall thereupon terminate. Notwithstanding anything herein to the

contrary, if subsequent to the Participant's termination, but prior to the

exercise of the Option, the Board of Directors of the Company determines that,

either prior or subsequent to the Participant's termination, the Participant

engaged in conduct which would constitute "cause," then the Participant shall

immediately cease to have any right to exercise the Option and this Option shall

thereupon terminate.

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In the event of the Disability of the Participant, as determined in

accordance with the Plan, the Option shall be exercisable within one year after

the Participant's termination of service or, if earlier, within the term

originally prescribed by the Option. In such event, the Option shall be

exercisable:

(a) to the extent that the Option has become exercisable but has not been

exercised as of the date of Disability; and

(b) in the event rights to exercise the Option accrue periodically, to the

extent of a pro rata portion through the date of Disability of any

additional vesting rights that would have accrued on the next vesting

date had the Participant not become Disabled. The proration shall be

based upon the number of days accrued in the current vesting period

prior to the date of Disability.

In the event of the death of the Participant while an employee, director or

consultant of the Company or of an Affiliate, the Option shall be exercisable by

the Participant's Survivors within one year after the date of death of the

Participant or, if earlier, within the originally prescribed term of the Option.

In such event, the Option shall be exercisable:

(x) to the extent that the Option has become exercisable but has not been

exercised as of the date of death; and

(y) in the event rights to exercise the Option accrue periodically, to the

extent of a pro rata portion through the date of death of any

additional vesting rights that would have accrued on the next vesting

date had the Participant not died. The proration shall be based upon

the number of days accrued in the current vesting period prior to the

Participant's date of death.

5. METHOD OF EXERCISING OPTION.

Subject to the terms and conditions of this Agreement, the Option may be

exercised by written notice to the Company or its designee, in substantially the

form of Exhibit A attached hereto. Such notice shall state the number of Shares

with respect to which the Option is being exercised and shall be signed by the

person exercising the Option. Payment of the Purchase Price for such Shares

shall be made in accordance with Paragraph 8 of the Plan. The Company shall

deliver a certificate or certificates representing such Shares as soon as

practicable after the notice shall be received, provided, however, that the

Company may delay issuance of such Shares until completion of any action or

obtaining of any consent, which the Company deems necessary under any applicable

law (including, without limitation, state securities or "blue sky" laws). The

certificate or certificates for the Shares as to which the Option shall have

been so exercised shall be registered in the Company's share register in the

name of the person so exercising the Option (or, if the Option shall be

exercised by the Participant and if the Participant shall so request in the

notice exercising the Option, shall be registered in the name of the Participant

and another person jointly, with right of survivorship) and shall be delivered

as provided above to or upon the written order of the person exercising the

Option. In the event the Option shall be exercised, pursuant to Section 4

hereof, by any person other than the Participant,

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such notice shall be accompanied by appropriate proof of the right of such

person to exercise the Option. All Shares that shall be purchased upon the

exercise of the Option as provided herein shall be fully paid and nonassessable.

6. PARTIAL EXERCISE.

Exercise of this Option to the extent above stated may be made in part at

any time and from time to time within the above limits, except that no

fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY.

The Option shall not be transferable by the Participant otherwise than by

will or by the laws of descent and distribution or pursuant to a qualified

domestic relations order as defined by the Code or Title I of the Employee

Retirement Income Security Act or the rules thereunder. However, the

Participant, with the approval of the Administrator, may transfer the Option for

no consideration to or for the benefit of the Participant's Immediate Family

(including, without limitation, to a trust for the benefit of the Participant's

Immediate Family or to a partnership or limited liability company for one or

more members of the Participant's Immediate Family), subject to such limits as

the Administrator may establish, and the transferee shall remain subject to all

the terms and conditions applicable to the Option prior to such transfer and

each such transferee shall so acknowledge in writing as a condition precedent to

the effectiveness of such transfer. The term "Immediate Family" shall mean the

Participant's spouse, former spouse, parents, children, stepchildren, adoptive

relationships, sisters, brothers, nieces, nephews and grandchildren (and, for

this purpose, shall also include the Participant.) Except as provided in the

previous sentence, the Option shall be exercisable, during the Participant's

lifetime, only by the Participant (or, in the event of legal incapacity or

incompetency, by the Participant's guardian or representative) and shall not be

assigned, pledged or hypothecated in any way (whether by operation of law or

otherwise) and shall not be subject to execution, attachment or similar process.

Any attempted transfer, assignment, pledge, hypothecation or other disposition

of the Option or of any rights granted hereunder contrary to the provisions of

this Section 7, or the levy of any attachment or similar process upon the Option

shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE.

The Participant shall have no rights as a stockholder with respect to

Shares subject to this Agreement until registration of the Shares in the

Company's share register in the name of the Participant. Except as is expressly

provided in the Plan with respect to certain changes in the capitalization of

the Company, no adjustment shall be made for dividends or similar rights for

which the record date is prior to the date of such registration.

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9. ADJUSTMENTS.

The Plan contains provisions covering the treatment of Options in a number

of contingencies such as stock splits and mergers. Provisions in the Plan for

adjustment with respect to stock subject to Options and the related provisions

with respect to successors to the business of the Company are hereby made

applicable hereunder and are incorporated herein by reference.

10. TAXES.

The Participant acknowledges that upon exercise of the Option the

Participant will be deemed to have taxable income measured by the difference

between the then fair market value of the Shares received upon exercise and the

price paid for such Shares pursuant to this Agreement. The Participant

acknowledges that any income or other taxes due from him or her with respect to

this Option or the Shares issuable pursuant to this Option shall be the

Participant's responsibility.

The Participant agrees that the Company may withhold from the Participant's

remuneration, if any, the minimum statutory amount of federal, state and local

withholding taxes attributable to such amount that is considered compensation

includable in such person's gross income. At the Company's discretion, the

amount required to be withheld may be withheld in cash from such remuneration,

or in kind from the Shares otherwise deliverable to the Participant on exercise

of the Option. The Participant further agrees that, if the Company does not

withhold an amount from the Participant's remuneration sufficient to satisfy the

Company's income tax withholding obligation, the Participant will reimburse the

Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT.

Unless the offering and sale of the Shares to be issued upon the particular

exercise of the Option shall have been effectively registered under the

Securities Act of 1933, as now in force or hereafter amended (the "1933 Act"),

the Company shall be under no obligation to issue the Shares covered by such

exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at

the time of such exercise, that such person(s) are acquiring such

Shares for their own respective accounts, for investment, and not with

a view to, or for sale in connection with, the distribution of any

such Shares, in which event the person(s) acquiring such Shares shall

be bound by the provisions of the following legend which shall be

endorsed upon the certificate(s) evidencing the Shares issued pursuant

to such exercise:

"The shares represented by this certificate have been taken for

investment and they may not be sold or otherwise transferred by

any person, including a pledgee, unless (1) either (a) a

Registration Statement with respect to such shares shall be

effective under the Securities Act of 1933, as amended, or (b)

the Company shall have received an opinion of counsel

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satisfactory to it that an exemption from registration under such

Act is then available, and (2) there shall have been compliance

with all applicable state securities laws;" and

(b) If the Company so requires, the Company shall have received an opinion

of its counsel that the Shares may be issued upon such particular

exercise in compliance with the 1933 Act without registration

thereunder. Without limiting the generality of the foregoing, the

Company may delay issuance of the Shares until completion of any

action or obtaining of any consent, which the Company deems necessary

under any applicable law (including without limitation state

securities or "blue sky" laws).

12. RESTRICTIONS ON TRANSFER OF SHARES.

12.1 The Shares acquired by the Participant pursuant to the exercise of the

Option granted hereby shall not be transferred by the Participant except as

permitted herein.

12.2 In the event of the Participant's termination of service for any

reason, the Company shall have the option, but not the obligation, to repurchase

all or any part of the Shares issued pursuant to this Agreement (including,

without limitation, Shares purchased after termination of employment, Disability

or death in accordance with Section 4 hereof). In the event the Company does

not, upon the termination of service of the Participant (as described above),

exercise its option pursuant to this Section 12.2, the restrictions set forth in

the balance of this Agreement shall not thereby lapse, and the Participant for

himself or herself, his or her heirs, legatees, executors, administrators and

other successors in interest, agrees that the Shares shall remain subject to

such restrictions. The following provisions shall apply to a repurchase under

this Section 12.2:

(i) The per share repurchase price of the Shares to be sold to the Company

upon exercise of its option under this Section 12.2 shall be equal to

the Fair Market Value of each such Share determined in accordance with

the Plan as of the date of termination of service.

(ii) The Company's option to repurchase the Participant's Shares in the

event of termination of service shall be valid for a period of 18

months commencing with the date of such termination of service.

(iii) In the event the Company shall be entitled to and shall elect to

exercise its option to repurchase the Participant's Shares under this

Section 12.2, the Company shall notify the Participant, or in case of

death, his or her Survivor, in writing of its intent to repurchase the

Shares. Such written notice may be mailed by the Company up to and

including the last day of the time period provided for in Section

12.2(ii) for exercise of the Company's option to repurchase.

(iv) The written notice to the Participant shall specify the address at,

and the time and date on, which payment of the repurchase price is to

be made (the "Closing").

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The date specified shall not be less than ten days nor more than 60

days from the date of the mailing of the notice, and the Participant

or his or her successor in interest with respect to the Shares shall

have no further rights as the owner thereof from and after the date

specified in the notice. At the Closing, the repurchase price shall be

delivered to the Participant or his or her successor in interest and

the Shares being purchased, duly endorsed for transfer, shall, to the

extent that they are not then in the possession of the Company, be

delivered to the Company by the Participant or his or her successor in

interest.

12.3 It shall be a condition precedent to the validity of any sale or other

transfer of any Shares by the Participant that the following restrictions be

complied with (except as hereinafter otherwise provided):

(i) No Shares owned by the Participant may be sold, pledged or otherwise

transferred (including by gift or devise) to any person or entity,

voluntarily, or by operation of law, except in accordance with the

terms and conditions hereinafter set forth.

(ii) Before selling or otherwise transferring all or part of the Shares,

the Participant shall give written notice of such intention to the

Company, which notice shall include the name of the proposed

transferee, the proposed purchase price per share, the terms of

payment of such purchase price and all other matters relating to such

sale or transfer and shall be accompanied by a copy of the binding

written agreement of the proposed transferee to purchase the Shares of

the Participant. Such notice shall constitute a binding offer by the

Participant to sell to the Company such number of the Shares then held

by the Participant as are proposed to be sold in the notice at the

monetary price per share designated in such notice, payable on the

terms offered to the Participant by the proposed transferee (provided,

however, that the Company shall not be required to meet any

non-monetary terms of the proposed transfer, including, without

limitation, delivery of other securities in exchange for the Shares

proposed to be sold). The Company shall give written notice to the

Participant as to whether such offer has been accepted in whole by the

Company within sixty days after its receipt of written notice from the

Participant. The Company may only accept such offer in whole and may

not accept such offer in part. Such acceptance notice shall fix a

time, location and date for the closing on such purchase ("Closing

Date") which shall not be less than ten nor more than sixty days after

the giving of the acceptance notice, provided, however, if any of the

Shares to be sold pursuant to this Section 12.3 have been held by the

Participant for less than six months, then the Closing Date may be

extended by the Company until no more than ten days after such Shares

have been held by the Participant for six months. The place for such

closing shall be at the Company's principal office. At such closing,

the Participant shall accept payment as set forth herein and shall

deliver to the Company in exchange therefor certificates for the

number of Shares stated in the notice accompanied by duly executed

instruments of transfer.

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(iii) If the Company shall fail to accept any such offer, the Participant

shall be free to sell all, but not less than all, of the Shares set

forth in his or her notice to the designated transferee at the price

and terms designated in the Participant's notice, provided that (i)

such sale is consummated within six months after the giving of notice

by the Participant to the Company as aforesaid, and (ii) the

transferee first agrees in writing to be bound by the provisions of

this Section 12 so that such transferee (and all subsequent

transferees) shall thereafter only be permitted to sell or transfer

the Shares in accordance with the terms hereof. After the expiration

of such six months, the provisions of this Section 12.3 shall again

apply with respect to any proposed voluntary transfer of the

Participant's Shares.

(iv) The restrictions on transfer contained in this Section 12.3 shall not

apply to (a) transfers by the Participant to his or her spouse or

children or to a trust for the benefit of his or her spouse or

children, (b) transfers by the Participant to his or her guardian or

conservator, and (c) or transfers by the Participant, in the event of

his or her death, to his or her executor(s) or administrator(s) or to

trustee(s) under his or her will (collectively, "Permitted

Transferees"); provided however, that in any such event the Shares so

transferred in the hands of each such Permitted Transferee shall

remain subject to this Agreement, and each such Permitted Transferee

shall so acknowledge in writing as a condition precedent to the

effectiveness of such transfer.

(v) The provisions of this Section 12.3 may be waived by the Company. Any

such waiver may be unconditional or based upon such conditions as the

Company may impose.

12.4 In the event that the Participant or his or her successor in interest

fails to deliver the Shares to be repurchased by the Company under this

Agreement, the Company may elect (a) to establish a segregated account in the

amount of the repurchase price, such account to be turned over to the

Participant or his or her successor in interest upon delivery of such Shares,

and (b) immediately to take such action as is appropriate to transfer record

title of such Shares from the Participant to the Company and to treat the

Participant and such Shares in all respects as if delivery of such Shares had

been made as required by this Agreement. The Participant hereby irrevocably

grants the Company a power of attorney which shall be coupled with an interest

for the purpose of effectuating the preceding sentence.

12.5 If the Company shall pay a stock dividend or declare a stock split on

or with respect to any of its Common Stock, or otherwise distribute securities

of the Company to the holders of its Common Stock, the number of shares of stock

or other securities of Company issued with respect to the shares then subject to

the restrictions contained in this Agreement shall be added to the Shares

subject to the Company's rights to repurchase pursuant to this Agreement. If the

Company shall distribute to its stockholders shares of stock of another

corporation, the shares of stock of such other corporation, distributed with

respect to the Shares then subject to the restrictions contained in this

Agreement, shall be added to the Shares subject to the Company's rights to

repurchase pursuant to this Agreement.

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12.6 If the outstanding shares of Common Stock of the Company shall be

subdivided into a greater number of shares or combined into a smaller number of

shares, or in the event of a reclassification of the outstanding shares of

Common Stock of the Company, or if the Company shall be a party to a merger,

consolidation or capital reorganization, there shall be substituted for the

Shares then subject to the restrictions contained in this Agreement such amount

and kind of securities as are issued in such subdivision, combination,

reclassification, merger, consolidation or capital reorganization in respect of

the Shares subject immediately prior thereto to the Company's rights to

repurchase pursuant to this Agreement.

12.7 The Company shall not be required to transfer any Shares on its books

which shall have been sold, assigned or otherwise transferred in violation of

this Agreement, or to treat as owner of such Shares, or to accord the right to

vote as such owner or to pay dividends to, any person or organization to which

any such Shares shall have been so sold, assigned or otherwise transferred, in

violation of this Agreement.

12.8 The provisions of Sections 12.1, 12.2 and 12.3 shall terminate upon

the consummation of a public offering of any of the Company's securities

pursuant to a registration statement filed with the Securities and Exchange

Commission.

12.9 The Employee agrees that in the event that the Company effects an

initial public offering of the Common Stock of the Company registered under the

Securities Act, the Shares may not be sold, offered for sale or otherwise

disposed of, directly or indirectly, without the prior written consent of the

managing underwriter(s) of the offering, for such period of time after the

execution of an underwriting agreement in connection with the such offering that

all of the Company's then directors and executive officers agree to be similarly

bound.

12.10 The Participant acknowledges and agrees that neither the Company, its

shareholders nor its directors and officers, has any duty or obligation to

disclose to the Participant any material information regarding the business of

the Company or affecting the value of the Shares before, at the time of, or

following a termination of the employment of the Participant by the Company,

including, without limitation, any information concerning plans for the Company

to make a public offering of its securities or to be acquired by or merged with

or into another firm or entity.

12.11 All certificates representing the Shares to be issued to the

Participant pursuant to this Agreement shall have endorsed thereon a legend

substantially as follows: "The shares represented by this certificate are

subject to restrictions set forth in a Non-Qualified Stock Option Agreement

dated ________, 200__ with this Company, a copy of which Agreement is available

for inspection at the offices of the Company or will be made available upon

request."

13. NO OBLIGATION TO MAINTAIN RELATIONSHIP.

The Company is not by the Plan or this Option obligated to continue the

Participant as an employee, director or consultant of the Company or an

Affiliate. The Participant acknowledges: (i) that the Plan is discretionary in

nature and may be suspended or terminated by the Company at any time; (ii) that

the grant of the Option is a one-time benefit which does not create any

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contractual or other right to receive future grants of options, or benefits in

lieu of options; (iii) that all determinations with respect to any such future

grants, including, but not limited to, the times when options shal