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                                                                   EXHIBIT 10.27

                   WESTERN WIRELESS INTERNATIONAL CORPORATION
                AMENDED AND RESTATED 1998 STOCK APPRECIATION PLAN

     1.   ESTABLISHMENT AND PURPOSE. This 1998 Stock Appreciation Plan was
established to provide an important inducement for management to generate
shareholder value by giving certain key personnel of Western Wireless
International Corporation and its Subsidiaries a stake in the equity value of
the Company. The Company believes that the managers participating in the, Plan
will seek to build personal financial security through creating and maintaining
value in the Company for all shareholders.

     2.   DEFINITIONS. As used herein, the following definitions shall apply:

          "Account" means the account established and maintained in accordance
with Section 5 hereof.

          "Administrator" means the Board or any Committee designated by the
Board to Administer the Plan in accordance with Section 4 hereof.

          "Board" means the Board of Directors of the Company, as constituted
from time to time.

          "Code" means the Internal Revenue Code Of 1986, as amended.

          "Committee" means a committee appointed by the Board, in accordance
with Section 4 hereof. If no such committee has been appointed, "Committee"
means the full Board.

          "Company" means Western Wireless International Corporation, a Delaware
corporation.

          "Consultant" shall mean any person engaged by the Company who is not
an Employee.

          "Director" means a member of the Board.

          "Disability" means total and permanent disability as defined in
Section 22(e)(3) of the Code.

          "Employee" means any person, including an Officer or Director, who is
an employee (within the meaning of Section 3401(c) of the Code and the
regulations thereunder) of the Company or a Subsidiary.

          "Fair Market Value" means value determined pursuant to Section 8
hereof.

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          "Participant" means an Employee, Director or Consultant who holds an
outstanding Performance Unit.

          "Performance Unit" means an interest in the rights awarded and
available for award under the Plan, as provided in Section 5 hereof.

          "Plan" means this 1998 Stock Appreciation Plan of Western Wireless
International Corporation, as it may be amended.

          "Subsidiary" means a "subsidiary corporation" (other than the
Company), whether now or hereafter existing, as defined in Section 424(f) of the
Code.

     3.   GRANTS. Performance Units shall be granted to such Employees,
Directors and Consultants as the Administrator shall determine, who shall
hereafter be referred to as "Participants." The number of Performance Units that
may be awarded under the Plan shall not exceed an aggregate of 28,000. If any
Performance Units awarded under the Plan shall be forfeited or cancelled, such
Performance Units may again be awarded under the Plan. Performance Units shall
be granted at such time or times and shall be subject to such terms and
conditions, in addition to the terms and conditions set forth in the Plan, as
the Administrator shall determine.

     4.   ADMINISTRATION OF THE PLAN. The Plan shall be administered by a
Committee appointed by the Board consisting of two or more members of the Board.
If no such Committee is appointed, the Plan shall be administered by the Board.
The members of the Committee will serve for such term as the Board may
determine. From time to time, the Board may increase the size of the Committee
and appoint additional members, remove members, fill vacancies (however caused),
and remove all members of the Committee and thereafter directly administer the
Plan. Decisions of the Committee made within the discretion delegated to it by
the Board will be final and binding on all persons who have an interest in the
Plan.

          (a)  Authority of the Administrator. The Administrator of the Plan
will have full authority to administer the Plan within the scope of its
delegated responsibilities, consistent with the terms of the Plan, including
authority to interpret and construe any relevant provision of the Plan, to adopt
such rules and regulations as it may deem necessary, and to determine the terms
and conditions of Performance Unit grants made under the Plan (which need not be
identical). Without limiting the foregoing, the Administrator will have the
authority, in its discretion:

               (i)  to determine whether and to what extent Performance Units
are granted hereunder;

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               (ii) to select the Employees. Directors and Consultants to whom
Performance Units may be granted hereunder;

               (iii) to determine the number of Performance Units to be granted
hereunder to any Employee, Director or Consultant, provided, that the maximum
number of Performance Units outstanding at any time shall not exceed 28,000;

               (iv) to determine the Fair Market Value of the Performance Units;

               (v)  to approve forms for notice of the grant of Performance
Units for use under the Plan;

               (vi) to determine the terms and conditions, not inconsistent with
those of the Plan, of any award of Performance Units granted hereunder,
including, but not limited to, all vesting provisions; any waiver of forfeiture
restrictions; and any restriction or limitation regarding any Performance Units
based on such factors as the Administrator, in its sole discretion, shall
determine;

               (vii) with the consent of the affected Participant, to effect, at
any time and from time to time, the cancellation of any or all outstanding
Performance Units under the Plan and to grant new Performance Units in
substitution therefor, in accordance with Section 13 hereof;

               (viii) to prescribe, amend and rescind rules and regulations
relating to the Plan;

               (ix) to modify, amend or waive the terms, conditions and
restrictions of any outstanding Performance Units; provided, however, no such
modification, amendment or waiver shall, without the written consent of the
Participant, impair the Participant's rights or increase the Participant's
obligations with respect to such Performance Units;

               (x)  to institute a Performance Unit Exchange Program (as defined
in Section 13); and

               (xi) to make all other determinations deemed necessary or
advisable for administering the Plan.

          (b)  Effect of Administrator's Decision. The Administrator's
decisions, determinations and interpretations shall be final and binding on all
Participants.

     5.   PERFORMANCE UNITS. Performance Units granted to a Participant shall be
credited to a Performance Unit Account (the "Account") established and
maintained for such participant. The Account of a Participant shall be the
record of Performance Units granted to him under the Plan, is solely for
accounting purposes and shall not require a segregation of any Company assets.
Each Performance Unit shall be valued at its fair market value by the

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Committee, in the manner provided in Section 8, as of the date of grant thereof.
Each grant of any Performance Units under the Plan to a Participant and the
value of such Performance Units as of the date of grant shall be communicated by
the Administrator, in writing to the Participant within thirty (30) days after
the date of grant.

     6.   VESTING OF PERFORMANCE UNITS. Subject to any other vesting schedule
determined by the Administrator at the time of grant thereof, Performance Units
granted to a Participant shall vest according to the following schedule:

<TABLE>
<CAPTION>
     Anniversary of Grant Date          Percentage of Performance Units Vested
     -------------------------          --------------------------------------
<S>                                     <C>
             First                                       25%
             Second                                      50%
             Third                                       75%
             Fourth                                     100%
</TABLE>

     7.   PAYMENT FOR PERFORMANCE UNITS.

          (a)       (i) Upon receipt of written notice in the form acceptable to
the Committee from a Participant of his or her surrender of all or a portion of
such Participant's vested Performance Units and (ii) three months after the date
of the termination of employment of a Participant with the Company for any
reason (other than as provided in Section 7(c), below), the Participant shall be
entitled to receive from the Company with respect to each then vested
Performance Unit in the Participant's Account as to which the Participant has
given a notice of surrender, or with respect to each then vested Performance
Unit in the Participant's Account at the termination of employment, as the case
may be, an amount determined as follows: (x) the Fair Market Value of each such
Performance Unit in the Participant's Account as to which the Participant has
given notice of surrender or the Fair Market Value of all such Performance Units
in the Participant's Account at the date of termination of his employment with
the Company, as the case may be, reduced by (y) the Fair Market Value of such
Performance Unit as of the date of grant thereof to the Participant.

          (b)       Payment to a Participant of the amount set forth in
paragraph (a) next above for Performance Units shall be made in cash either in a
lump sum or in equal bi-annual installments over a period not to exceed 3 years.
The Administrator shall have the sole discretion to determine the method of
payment under the Plan and the period over which such payment shall be made.
Payment will be made or commence within ninety (90) days after the applicable
date referred to in Section 7(a)(i) or (ii). A Participant will not be entitled
to receive any earnings on the value of his Performance Units with respect to
the period between the date referred to in Section 7(a)(i) or, if Participant's
entitlement arises under Section 7(a)(ii), the date of termination of employment
and the receipt of payments under the Plan.

     8.   VALUATION OF PERFORMANCE UNITS. For all purposes of the Plan, the Fair
Market Value of a Performance Unit and of the common stock of the Company as of
the date of grant, as of the date of exercise and as of the date of termination
of employment shall be

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the Fair Market Value as determined by the Administrator as of the January 1
immediately preceding each such date. For purposes of determining Fair Market
Value, the 28,000 Performance Units subject to the Plan shall have an aggregate
Fair Market Value at any time equal to 7% of the Fair Market Value at such time
of all the shares of common stock of the Company that were outstanding at
January 1, 1998. The aggregate Fair Market Value of all the outstanding common
stock of the Company at January 1, 1998 (without regard to Performance Units)
shall be deemed to be $80 million and the Fair Market Value of each Performance
Unit at that time shall be deemed to be $200.

     9.   FORFEITURE OF PERFORMANCE UNITS. If (i) the employment of a
Participant with the Company is terminated for any reason or (ii) the owner of a
majority of shares of capital stock of the Company terminates the business of,
or liquidates or dissolves, the Company; (iii) substantially all of the assets
of the Company are sold, or (iv) the Company merges or consolidates with any
other corporation and either the Company is not the surviving corporation of
such merger or consolidation or the owners of the common stock of the Company
immediately before such merger or consolidation do not own, directly or
indirectly, as a result of such ownership, at least a majority of the common
stock of the surviving corporation of the merger or consolidation, then each
Participant's rights with respect to Performance Units which have not vested on
or prior to the date of the occurrence of such event will terminate and be
forfeited and neither the Participant nor his heirs, personal representatives,
successors or assigns shall have any future rights with respect to any such
Performance Units.

     10.  CHANGES IN CAPITAL AND CORPORATE STRUCTURE. In the event of any change
in the outstanding shares of common stock of the Company by reason of a
recapitalization, reclassification, reorganization, stock split, reverse stock
split, combination of shares, stock dividend or similar transaction, the
Administrator shall proportionately adjust, in an equitable manner, the number
of Performance Units held by Participants under the Plan to maintain the
relationship between 28,000 Performance Units and 7% of outstanding common stock
of the Company at January 1, 1998. The foregoing adjustment shall be made in a
manner that will cause the relationship between the aggregate appreciation in
outstanding common stock of the Company and the increase in value of each
Performance Unit granted hereunder to remain unchanged as a result of the
applicable transaction.

     11.  NONTRANSFERABILITY. Performance Units granted under the Plan, and any
rights and privileges pertaining thereto, may not be transferred, assigned,
pledged or hypothecated in any manner, by operation of law or otherwise, other
than by will or by the laws of descent and distribution, and shall not be
subject to execution, attachment or similar process. In the event of a
Participant's death, payment of any amount due under the Plan shall be made to
the duly appointed and qualified executor or other personal representative of
the Participant to be distributed in accordance with the Participant's will or
applicable intestacy law, or in the event that there shall be no such
representative duly appointed and qualified within six (6) months after the date
of death of such deceased Participant, then to such persons as, at the date of
his death, would be entitled to share in the distribution of such deceased
Participant's personal estate under the provisions of the applicable statute
then in force governing the descent of intestate property, in the proportions
specified in such statute.

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     12.  WITHHOLDING. The Company shall have the right to deduct from all
amounts paid pursuant to the Plan any taxes required by law to be withheld with
respect to such awards.

     13.  PERFORMANCE UNIT EXCHANGE PROGRAM. The Administrator will have the
authority to effect, at any time and from time to time, with the consent of the
affected Participants, the cancellation of any or all outstanding Performance
Units under the Plan and to grant in substitution therefor new Performance Units
under the Plan.

     14.  VOTING AND DIVIDEND RIGHTS. No Participant shall be entitled to any
voting rights, to receive any dividends, or, except as provided under Section
10, to have his Account credited or increased as a result of any dividends or
other distribution with respect to the common stock of the Company.

     15.  MISCELLANEOUS PROVISIONS.

          (a)  No Employee, Director, Consultant or other person shall have any
claim or right to be granted an award under the Plan.

          (b)  The Plan shall at all times be entirely unfunded and no provision
shall at any time be made with respect to segregating assets of the Company for
payment of any benefits hereunder. No Participant or other person shall have any
interest in any particular assets of the Company by reason of the right to
receive a benefit under the Plan and any such Participant or other person shall
have only the rights of a general unsecured creditor of the Company with respect
to any rights under the Plan.

          (c)  Except when otherwise required by the context, any masculine
terminology in this document shall include the feminine, and any singular
terminology shall include the plural.

     16.  EFFECTIVENESS AND TERMS OF PLAN. The effective date of the Plan shall
be January 1, 1998. The Administrator may at any time terminate the Plan and
unless sooner terminated by the Committee, the Plan shall terminate on December
31, 2008. No Performance Units shall be granted pursuant to the Plan after the
date of termination of the Plan, although after such date payments shall be made
with respect to Performance Units granted prior to the date of termination.

     17.  NO EMPLOYMENT RIGHTS. Neither the Plan nor any Performance Units shall
confer upon any Employee, Director or Consultant any right to continue in the
employ of the Company of any affiliate or constitute a contract or agreement of
employment or interfere in any way with any right that the Company or an
affiliate may have to reduce such person's compensation or to terminate such
person's employment at any time with or without cause; however, nothing
contained in the Plan or in any Performance Unit granted under the Plan shall
affect any contractual rights of an Employee, Director or Consultant pursuant to
a written employment or other agreement.

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     18.  AMENDMENT AND TERMINATION OF THE PLAN.

          (a)  Amendment and Termination. The Board may at any time amend,
alter, suspend or terminate the Plan in whole or in part.

          (b)  Effect of Amendment or Termination. No amendment, alteration,
suspension or termination of the Plan shall impair the rights or increase the
obligations of any Participant, unless mutually agreed otherwise between the
Participant and the Administrator, which agreement must be in writing and signed
by the Participant and the Company.

     19.  GOVERNING LAW. The Plan shall be governed by and construed in
accordance with the laws of the state of Delaware.

                                       7Exhibit 10.12

                            CERTIFICATE OF AMENDMENT

                                     OF THE

                          CERTIFICATE OF INCORPORATION

                                       OF

                            HUDSON TECHNOLOGIES, INC.

                Under Section 805 of the Business Corporation Law

The  undersigned,  being the  Chairman  and Chief  Executive  Officer  of HUDSON
TECHNOLOGIES, INC. (the "Corporation") hereby certifies:

1.   The name of the  Corporation  is HUDSON  TECHNOLOGIES,  INC.  It was formed
     under the name REFRIGERANT RECLAMATION INDUSTRIES, INC.

2.   The Certificate of Incorporation  was filed with the Department of State on
     January 11, 1991.

3.   On March 30, 1999, the Board of Directors of the  Corporation  duly adopted
     resolutions in order to designate  seventy-five thousand (75,000) shares of
     the  Corporation's  Series A  Convertible  Preferred  Stock (the  "Series A
     Preferred Stock").

4.   On February  15,  2001,  the Board of  Directors  of the  Corporation  duly
     authorized resolutions in order to increase the number of shares designated
     as Series A Preferred  Stock from  seventy  five  thousand  (75,000) to one
     hundred fifty thousand (150,000).

5.   On March 5, 2002, the Board of Directors of the Corporation duly authorized
     resolutions  in  order  to  amend  Section  5(d)(ii)  of the  Corporation's
     Certificate of Incorporation  relating to the adjustments to the Conversion
     Price of the Series A Preferred Stock

6.   The Certificate of Incorporation is amended as authorized by Section 801 of
     the  Business  Corporation  Law to change  the  provision  of the  Series A
     Preferred Stock relating to adjustment of the Conversion Price.

7.   To effectuate  the foregoing,  Section  5(d)(ii) is deleted in its entirety
     and a new Section  5(d)(ii) is hereby  inserted in lieu and instead thereof
     to read as follows:

               "(ii) Issuance of Additional  Shares of Stock. If the Corporation
          shall (except as hereinafter provided) issue or sell Additional Shares
          of Stock in exchange  for  consideration  in an amount per  Additional
          Share of Stock less than the  Conversion  Price in effect  immediately
          prior to such issuance or sale of Additional Shares of Stock, then the
          Conversion  Price as to the  Common  Stock  into  which  the  Series A
          Preferred  Stock is convertible  immediately  prior to such adjustment
          shall be  adjusted to equal the higher of (a) the  consideration  paid
          per  Additional  Share of Stock or (b) $1.78.  The  provisions of this
          Section 5(d)(ii) shall not apply to any issuance of Additional  Shares
          of Common  Stock for which an  adjustment  is provided  under  Section
          5(d)(i)  or which  are  dividends  or  distributions  received  by the
          holders of the  Series A  Preferred  Stock  pursuant  to Section  2(b)
          hereof."

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8.   The amendment of the  Certificate  of  Incorporation  was authorized by the
     unanimous  vote of the  members of the Board of  Directors  taken at a duly
     authorized  meeting of the Board of Directors and by the unanimous  written
     consent,  setting forth the action taken, signed by all of the shareholders
     entitled to vote thereon.

     IN WITNESS WHEREOF,  I have hereunto executed this Certificate of Amendment
and do affirm the foregoing as true under the penalties of perjury this 20th day
of March , 2002.

                                                  By: /s/Kevin J. Zugibe
                                                         ---------------
                                                      Kevin J. Zugibe,
                                                      Chairman of the Board and
                                                      Chief Executive Officer

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                            CERTIFICATE OF AMENDMENT

                                     OF THE

                          CERTIFICATE OF INCORPORATION

                                       OF

                            HUDSON TECHNOLOGIES, INC.

                Under Section 805 of the Business Corporation Law

                        BLANK ROME TENZER GREENBLATT LLP
                              The Chrysler Building
                              405 Lexington Avenue
                            New York, New York 10174

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