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                                                                     Exhibit 4.4

                                SIPEX CORPORATION

           NON-QUALIFIED STOCK OPTION AGREEMENT STAGED EXERCISABILITY

           SIPEX Corporation, a Massachusetts corporation (the "Corporation")
hereby grants the following stock option pursuant to its 2000 Non-Qualified
Stock Option Plan. The terms and conditions attached hereto are also a part
hereof.

         Name of Optionee (the "Optionee"):

         Date of this option grant:

         Number of shares of the Corporation's
         Common Stock subject to this
         option ("Option Shares"):

         Option exercise price per share:

         Number, if any, of Option Shares that
         may be immediately purchased on
         or after grant date:

         Number of Option Shares subject to
         vesting schedule:

         Vesting Start Date:

           Vesting Schedule:

         One year from Vesting Start Date:      [an additional] __________shares

         Two years from Vesting Start Date:     an additional _______ shares

         Three years from Vesting Start Date:   an additional _______ shares

         Four years from Vesting Start Date:    an additional _______ shares

         Five years from Vesting Start Date:    all remaining shares


         Payment alternatives:
                                                Section 7(a) (i) through (iv)



____________________________________
                                             SIPEX CORPORATION
Signature of Optionee                        By:________________________________
                                                 Name of Officer:
                                                 Title:
____________________________________
Street Address


____________________________________
City/State/Zip Code
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                                SIPEX CORPORATION

    NON-QUALIFIED STOCK OPTION AGREEMENT -- INCORPORATED TERMS AND CONDITIONS


           1. Grant Under Plan. This option is granted pursuant to and is
governed by the Corporation's 2000 Non-Qualified Stock Option Plan (the "Plan")
and, unless the context otherwise requires, terms used herein shall have the
same meaning as in the Plan. Determinations made in connection with this option
pursuant to the Plan shall be governed by the Plan as it exists on this date. In
the event of any conflict between this Agreement and the provisions of the Plan,
the Plan shall govern.


           2. Grant as Non-Qualified Stock Option. This option is intended to be
a non-qualified stock option and is not intended to qualify as an incentive
stock option under Section 422 of the Internal Revenue Code of 1986, as amended,
and the regulations thereunder (the "Code").

           3. Vesting of Option if Business Relationship Continues. The Optionee
may exercise this option on or after the date of this option grant for the
number of shares of Common Stock, if any, indicated on the cover page hereof. If
the Optionee has continuously served the Corporation or any Related Entity (as
defined in the Plan) as an employee, consultant or advisor (such service is
described herein as maintaining or being involved in a "Business Relationship")
through the dates listed on the vesting schedule set forth on the cover page
hereof, the Optionee may exercise this option for the additional number of
shares of Common Stock set opposite the applicable vesting date. Notwithstanding
the foregoing, the Board may, in its discretion, accelerate the date that any
installment of this option becomes exercisable. The foregoing rights are
cumulative and (subject to Sections 4 or 5 hereof if the Optionee ceases to
maintain a Business Relationship with the Corporation and all Related Entities
may be exercised only before the date which is ten years from the date of this
option grant.

           4. Termination of Employment.

                      (a) Termination Other Than for Cause. If the Optionee
           ceases his or her Business Relationship with the Corporation and all
           Related Entities, other than by reason of death or disability as
           defined in Section 5 or termination for Cause as defined in Section
           4(c), no further installments of this option shall become
           exercisable, and this option may no longer be exercised after the
           passage of three months from the date of termination of the
           Optionee's Business Relationship, but in no event later than the
           scheduled expiration date. For purposes hereof, the Business
           Relationship with the Corporation or any Related Entity shall include
           a consulting arrangement between the Optionee and the Corporation or
           any Related Entity that immediately follows termination of
           employment, but only if so stated in a written consulting agreement
           executed by the Corporation or any Related Entity that specifically
           refers to this option. This option shall not be affected by any
           change of duties within or among the Corporation and Related Entity
           so long as the Optionee continuously maintains his or her Business
           Relationship with the Corporation or any Related Entity.

                      (b) Termination for Cause. If the Optionee's Business
           Relationship is terminated for Cause (as defined in Section 4(c)),
           this option shall expire (that is, may no longer be exercised), upon
           the Optionee's receipt of written notice of such termination and
           shall thereafter not be exercisable to any extent whatsoever.

                      (c) Definition of Cause. "Cause" shall mean conduct
           involving one or more of the following: (i) the substantial and
           continuing failure of the Optionee, after notice thereof, to render
           services to the Corporation or any Related Entity in accordance with
           the terms or requirements of his or her Business Relationship; (ii)
           disloyalty, gross negligence, willful misconduct, dishonesty, fraud
           or breach of fiduciary duty to the Corporation or any Related Entity;
           (iii) the commission of an act of embezzlement or fraud; (iv)
           deliberate disregard of the rules or policies of the Corporation or
           any Related Entity, or breach of an employment or other agreement
           with the Corporation or any Related Entity, which results in direct
           or indirect loss, damage or injury to the Corporation or any Related
           Entity; (v) the unauthorized disclosure of any trade secret or
           confidential information of the Corporation or any Related Entity; or
           (vi) the commission of an act which constitutes unfair competition
           with the Corporation or any Related Entity or which induces any
           customer or supplier to breach a contract with the Corporation or any
           Related Entity.
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           5. Death; Disability.

                      (a) Death. If the Optionee dies while in a Business
           Relationship with the Corporation or any Related Entity, this option
           may be exercised, to the extent otherwise exercisable on the date of
           his or her death, by the Optionee's estate, personal representative
           or beneficiary to whom this option has been transferred pursuant to
           Section 10, only at any time within 180 days after the date of death,
           but not later than the scheduled expiration date.

                      (b) Disability. If the Optionee ceases his or her Business
           Relationship with the Corporation or any Related Entity by reason of
           his or her disability, this option may be exercised, to the extent
           otherwise exercisable on the date of termination of the Optionee's
           Business Relationship with the Corporation or any Related Entity,
           only at any time within 180 days after such termination of the
           Optionee's Business Relationship, but not later than the scheduled
           expiration date. For purposes hereof, "disability" means "permanent
           and total disability" as defined in Section 22(e)(3) of the Code.

           6. Partial Exercise. This option may be exercised in part at any time
and from time to time within the above limits, except that this option may not
be exercised for a fraction of a share.

           7. Payment of Exercise Price.

                      (a) Payment Options. The exercise price shall be paid by
           one or any combination of the following forms of payment that are
           applicable to this option, as indicated on the cover page hereof:

                      (i)        in cash or by check payable to the order of the
                                 Corporation; or

                      (ii)       subject to Section 7(b) below, if the Common
                                 Stock is then traded on a national securities
                                 exchange or on the Nasdaq National Market (or
                                 successor trading system), by delivery of
                                 shares of Common Stock having a fair market
                                 value (determined in accordance with the Plan)
                                 equal as of the date of exercise to the option
                                 price; or

                      (iii)      by delivery of an assignment satisfactory in
                                 form and substance to the Corporation of a
                                 sufficient amount of the proceeds from the sale
                                 of the Option Shares and an instruction to the
                                 broker or selling agent to pay that amount to
                                 the Company; or

                      (iv)       by any combination of the foregoing.

                      (b) Limitations on Payment by Delivery of Common Stock. If
           Section 7(a)(ii) is applicable, and if the Optionee delivers Common
           Stock held by the Optionee ("Old Stock") to the Corporation in full
           or partial payment of the exercise price and the Old Stock so
           delivered is subject to restrictions or limitations imposed by
           agreement between the Optionee and the Corporation, an equivalent
           number of Option Shares shall be subject to all restrictions and
           limitations applicable to the Old Stock to the extent that the
           Optionee paid for the Option Shares by delivery of Old Stock, in
           addition to any restrictions or limitations imposed by this
           Agreement. Notwithstanding the foregoing, the Optionee may not pay
           any part of the exercise price hereof by transferring Common Stock to
           the Corporation unless such Common Stock has been owned by the
           Optionee free of any substantial risk of forfeiture for at least six
           months.

           8. Securities Laws Restrictions on Resale. Until registered under the
Securities Act of 1933, as amended, or any successor statute (the "Securities
Act"), the Option Shares will be of an illiquid nature and will be deemed to be
"restricted securities" for purposes of the Securities Act. Accordingly, such
shares must be sold in compliance with the registration requirements of the
Securities Act or an exemption therefrom. Unless the Option Shares have been
registered under the Securities Act, each certificate evidencing any of the
Option Shares shall bear a legend substantially as follows:
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           "The shares represented by this certificate are subject to
           restrictions on transfer and may not be sold, exchanged, transferred,
           pledged, hypothecated or otherwise disposed of except in accordance
           with and subject to all the terms and conditions of a certain
           Non-Qualified Stock Option Agreement dated as of [________], a copy
           of which the Corporation will furnish to the holder of this
           certificate upon request and without charge."

           9. Method of Exercising Option. Subject to the terms and conditions
of this Agreement, this option may be exercised by written notice to the
Corporation, at its principal executive office, or to such transfer agent as the
Corporation shall designate. Such notice shall state the election to exercise
this option and the number of Option Shares for which it is being exercised and
shall be signed by the person or persons so exercising this option. Such notice
shall be accompanied by payment of the full purchase price of such shares, and
the Corporation shall deliver a certificate or certificates representing such
shares as soon as practicable after the notice shall be received. Such
certificate or certificates shall be registered in the name of the person or
persons so exercising this option (or, if this option shall be exercised by the
Optionee and if the Optionee shall so request in the notice exercising this
option, shall be registered in the name of the Optionee and another person
jointly, with right of survivorship). In the event this option shall be
exercised, pursuant to Section 5 hereof, by any person or persons other than the
Optionee, such notice shall be accompanied by appropriate proof of the right of
such person or persons to exercise this option.

           10. Transferability. This option is not transferable or assignable
except with the consent of the Corporation or by (i) a valid court order, (ii)
will, or (iii) the laws of descent and distribution. During the Optionee's
lifetime only the Optionee can exercise this option.

           11. No Obligation to Exercise Option. The grant and acceptance of
this option imposes no obligation on the Optionee to exercise it.

           12. No Obligation to Continue the Business Relationship. Neither the
Plan, this Agreement, nor the grant of this option imposes any obligation on the
Corporation to continue the Optionee's Business Relationship with the
Corporation or any Related Entity.

           13. No Rights as Stockholder until Exercise. The Optionee shall have
no rights as a stockholder with respect to the Option Shares until such time as
the Optionee has exercised this option by delivering a notice of exercise and
has paid in full the purchase price for the shares so exercised in accordance
with Section 9. Except as is expressly provided in the Plan with respect to
certain changes in the capitalization of the Corporation, no adjustment shall be
made for dividends or similar rights for which the record date is prior to such
date of exercise.

           14. Adjustments. Except as is expressly provided in the Plan with
respect to certain changes in the capitalization of the Corporation, no
adjustment shall be made for dividends or similar rights for which the record
date is prior to such date of exercise.

           15. Withholding Taxes. If the Corporation in its discretion
determines that it is obligated to withhold any tax in connection with the
exercise of this option, or in connection with the transfer of, or the lapse of
restrictions on, any Common Stock or other property acquired pursuant to this
option, the Optionee hereby agrees that the Corporation may withhold from the
Optionee's wages or other remuneration the appropriate amount of tax. At the
discretion of the Corporation, the amount required to be withheld may be
withheld in cash from such wages or other remuneration or in kind from the
Common Stock or other property otherwise deliverable to the Optionee on exercise
of this option. The Optionee further agrees that, if the Corporation does not
withhold an amount from the Optionee's wages or other remuneration sufficient to
satisfy the withholding obligation of the Corporation, the Optionee will make
reimbursement on demand, in cash, for the amount underwithheld.

           16. Arbitration. Any dispute, controversy, or claim arising out of,
in connection with, or relating to the performance of this Agreement or its
termination shall be settled by arbitration in Massachusetts pursuant to the
rules then obtaining of the American Arbitration Association. Any award shall be
final, binding and conclusive upon the parties and a judgment rendered thereon
may be entered in any court having jurisdiction thereof.

           17. Provision of Documentation to Optionee. By signing this Agreement
the Optionee acknowledges receipt of a copy of this Agreement and a copy of the
Plan.
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           18. Miscellaneous.

                      (a) Notices. All notices hereunder shall be in writing and
           shall be deemed given when sent by certified or registered mail,
           postage prepaid, return receipt requested, if to the Optionee, to the
           address set forth below or at the address shown on the records of the
           Corporation, and if to the Corporation, to the Corporation's
           principal executive offices, attention of the Corporate Secretary.

                      (b) Entire Agreement; Modification. This Agreement
           constitutes the entire agreement between the parties relative to the
           subject matter hereof, and supersedes all proposals, written or oral,
           and all other communications between the parties relating to the
           subject matter of this Agreement. This Agreement may be modified,
           amended or rescinded only by a written agreement executed by both
           parties.

                      (c) Fractional Shares. If this option becomes exercisable
           for a fraction of a share because of the adjustment provisions
           contained in the Plan, such fraction shall be rounded down.

                      (d) Capital Changes and Business Successions. 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
           Corporation are hereby made applicable hereunder and are incorporated
           herein by reference.

                      (e) Severability. The invalidity, illegality or
           unenforceability of any provision of this Agreement shall in no way
           affect the validity, legality or enforceability of any other
           provision.

                      (f) Successors and Assigns. This Agreement shall be
           binding upon and inure to the benefit of the parties hereto and their
           respective successors and assigns, subject to the limitations set
           forth in Section 10 hereof.

                      (g) Governing Law. This Agreement shall be governed by and
           interpreted in accordance with the laws of the Commonwealth of
           Massachusetts, without giving effect to the principles of the
           conflicts of laws thereof.