Document:

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                               OPTION CERTIFICATE
                          (Non-Statutory Stock Option)

         THIS IS TO CERTIFY that 3D Systems Corporation,  a Delaware corporation
(the  "Company"),  has  granted  to the  Non-Employee  Director  named  below  a
non-statutory  stock option (the  "Option") to purchase  shares of the Company's
Common Stock (the "Shares") upon the terms and conditions as follows:

                  Name of Optionee:

                  Address of Optionee:

                  Number of Shares:

                  Option Exercise Price:    $       per share

                  Date of Grant:

                  Option Expiration Date:

         Exercise Schedule:  The Option shall become exercisable in three annual
installments of $2,500 shares of Common Stock each (or the number of adjusted or
substituted   shares,   described  below),  on  the  first,   second  and  third
anniversaries of the Date of Grant.  Installments  shall be cumulative,  and the
Option may be exercised  as to any and all shares of Common Stock  covered by an
installment at any time after the installment  becomes  exercisable and prior to
the expiration or termination of the Option.

         Summary of Other  Terms:  This  Option is  defined in the Stock  Option
Agreement  (Non-Statutory  Stock  Option)  (the  "Option  Agreement")  which  is
attached  to this  Option  Certificate  (the  "Certificate")  as Annex  I.  This
Certificate  summarizes  certain of the  provisions of the Option  Agreement for
your  information,  but is not complete.  Your rights are governed by the Option
Agreement, not by this summary. The Company strongly suggests that you carefully
review the full Option Agreement prior to signing this Certificate or exercising
the Option.

         Among the terms of the Option Agreement are the following:

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         Cessation of Service as a Director:  While the Option terminates on the
Option  Expiration Date, it will terminate earlier if you cease to be a Director
of  the  Company.  If  your  directorship  ends  due to any  reason  other  than
resignation,  removal for cause or death,  the Option is exercisable at any time
prior to the earlier to occur of the Option  Expiration Date or three years from
the date of such termination. If your directorship terminates due to resignation
or  removal  for cause,  any  outstanding  portion  of the  Option  which is not
exercisable  immediately  prior to such  resignation or removal shall  terminate
immediately upon such resignation or removal.  If your  directorship  terminates
due to death while serving on the Board, any outstanding  portion of this Option
shall  become  exercisable  in full at any time prior to the earlier to occur of
the Expiration Date or three years after the date of death. If your directorship
terminates  due to death after  ceasing to serve as a Director,  and during such
period when the Option is  exercisable,  the Option will be  exercisable  at any
time prior to the earlier to occur of (i) the Option Expiration Date or (ii) the
later of (a) three years  following the date you cease serving as a Director and
(b) one year following the date of death. See Paragraph 5 of the attached Option
Agreement.

         Transfer:   The  Option  is  personal  to  you,  and  cannot  be  sold,
transferred,  assigned or otherwise  disposed of to any other person,  except on
your death. See Paragraph 16(d) of the attached Option Agreement.

         Exercise:  You can  exercise the Option  (once it is  exercisable),  in
whole or in part, by delivering to the Company a Notice of Exercise identical to
Exhibit "A"  attached  to the Option  Agreement,  accompanied  by payment of the
Exercise  Price for the Shares to be  purchased.  The Company may require you to
submit certain  written  reassurances to the Company with respect to your status
as a  shareholder.  The  Company  will then issue a  certificate  to you for the
Shares you have  purchased.  You are under no obligation to exercise the Option.
See Paragraph 4 of the attached Option Agreement.

         Adjustments upon Recapitalization: The Option contains provisions which
affect your rights in the event of stock splits,  stock  dividends,  mergers and
other major  corporate  reorganizations.  See Paragraph 7 of the attached Option
Agreement.

         Waiver: By signing this Certificate, you will be agreeing to all of the
terms  of  the  Option  Agreement,   including  those  not  summarized  in  this
Certificate.  You will waive your rights to options or stock which may otherwise
have been promised to you. See Paragraph 9 of the attached Option Agreement.

         Withholding:  The  Company  may  require  you to make any  arrangements
necessary  to insure  the  proper  withholding  of any  amount  of tax,  if any,
required  to be  withheld  by the  Company  as a result of the  exercise  of the
Option. See Paragraph 14 of the attached Option Agreement.

<PAGE>

                                    AGREEMENT

         3D Systems Corporation, a Delaware corporation (the "Company"), and the
above-named person (the "Optionee") each hereby agrees to be bound by all of the
terms and conditions of the Stock Option Agreement  (Non-Statutory Stock Option)
which is attached hereto as Annex I and incorporated herein by this reference as
if set forth in full in this document.

DATED:
      ----------------------
                                   3D SYSTEMS CORPORATION

                                   By:

                                   Its:     Vice President and General Counsel

                                   OPTIONEE

                                   Name:

                                   (Please   print  your  name exactly  as you
                                   wish it to appear on  any stock certificates
                                   issued to you upon    exercise   of   the
                                   Option)

<PAGE>

                                     ANNEX I

                             STOCK OPTION AGREEMENT
                          (Non-Statutory Stock Option)

         This STOCK  OPTION  AGREEMENT  (this  "Option  Agreement")  is made and
entered into as of the execution  date of the Option  Certificate to which it is
attached (the "Certificate") by and between 3D Systems  Corporation,  a Delaware
corporation (the "Company"), and ____________________ ("Optionee").

         Pursuant to the 3D Systems  Corporation  1996  Non-Employee  Director's
Stock Option Plan (the "Plan"), the Compensation  Committee (the "Committee") of
the Board of Directors of the Company has  authorized the grant to Optionee of a
non-statutory stock option to purchase shares of the Company's Common Stock (the
"Common Stock"),  subject to approval by the Company's shareholders and upon the
terms and subject to the  conditions  set forth in this Option  Agreement and in
the Plan.

         The Company and Optionee agree as follows:

         1.       Grant of Option.

                  The Company  hereby  grants to  Optionee  the right and option
(the  "Option"),  upon the terms and subject to the conditions set forth in this
Option Agreement,  to purchase in whole or in part, that number of shares of the
Common Stock (the "Shares") set forth in the  Certificate at the Option Exercise
Price set forth in the Certificate (the "Exercise Price").

         2.       Term of Option.

                  The Option shall terminate and expire on the Option Expiration
Date set forth in the Certificate,  unless sooner terminated as provided herein.
In no event shall the Option be  exercisable  after the  expiration of ten years
from the date it was granted.

         3.       Exercise Period.

                  (a) Subject to the  provisions  of Sections 3(b) and 5 of this
Option Agreement, the Option shall become exercisable (in whole or in part) upon
and  after the dates set forth  under the  caption  "Exercise  Schedule"  in the
Certificate.  The  installments  shall be  cumulative;  i.e.,  the Option may be
exercised,  as to any or all Shares  covered by an  installment,  at any time or
times after the installment  first becomes  exercisable and until  expiration or
termination of the Option.

<PAGE>

                  (b) Notwithstanding anything to the contrary contained in this
Option Agreement,  the Option may not be exercised,  in whole or in part, unless
and until any then-applicable  requirements of all federal, state and local laws
and regulatory  agencies shall have been fully complied with to the satisfaction
of the Company and its counsel.

         4.       Exercise of Option.

                  There is no obligation to exercise the Option,  in whole or in
part. The Option may be exercised,  in whole or in part, only by delivery to the
Company of:

                  (a)  written  Notice of  Exercise  identical  to  Exhibit  "A"
attached to the Option  Agreement  stating the number of shares of Common  Stock
then being purchased (the "Purchased Shares");

                  (b) payment of the  Exercise  Price of the  Purchased  Shares,
either (1) in cash (including  check, bank draft or money order) at the time the
Option is exercised, (2) delivery to the Company of other shares of Common Stock
having a fair market value on the date of exercise equal to the Option  Exercise
Price for the Shares being purchased;  except that (A) any portion of the Option
Exercise Price  representing a fraction of a Share shall in any event be paid in
cash and (B) no shares of the  Common  Stock  which have been held for less than
six months may be delivered in payment of the Option  Exercise  Price, or (3) by
use of a broker or other agent, or (4) any combination thereof; and

                  (c) if requested by the Company, a letter of investment intent
in such form and containing such provisions as the Company may require.

                  The exercise of the Option shall not be deemed to occur and no
shares of Common Stock will be issued by the Company upon exercise of the Option
until the Company has received payment of the Option Exercise Price in full. The
date of the  exercise of a stock  option shall be  determined  under  procedures
established  by the  Committee,  and,  as of the date of  exercise,  the  person
exercising  the Option shall be  considered  for all purposes to be the owner of
the Shares with respect to which the Option has been exercised.

                  This  Option  shall not be  exercisable  during  the first six
months of its term except in case of death as provided in Paragraphs 5 and 7(b).
Subject to Paragraph 5, each stock  option  shall be  exercisable  for ten years
from the Date of Grant.

                  Fair  market  value  of the  Common  Stock  shall  be the mean
between  the  following  prices,  as  applicable,  for the date as of which fair
market  value is to be  determined  as quoted in The Wall Street  Journal (or in
such  other  reliable  publication  as the  Committee,  in its  discretion,  may
determine to rely upon):  (i) if the Common  Stock is listed on a United  States
securities  exchange,  the highest and lowest  sales  prices per share of Common
Stock for such date on the principal United States securities  exchange on which
the Common Stock is listed, or (ii) if the

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Common  Stock is not listed on any such  exchange,  the highest and lowest sales
prices per share of the Common Stock for such date on the Nasdaq National Market
or any successor  system then in use. If there are no such sale price quotations
for the date as of which fair  market  value is to be  determined  but there are
such sale price quotations within a reasonable period both before and after such
date,  then fair market  value shall be  determined  by taking an average of the
means  between the highest and lowest sales prices per share of the Common Stock
as so quoted on the nearest  date before and the nearest  date after the date as
of which fair market value is to be determined.  If there are no such sale price
quotations on or within a reasonable period both before and after the date as of
which fair  market  value is to be  determined,  then fair  market  value of the
Common  Stock shall be the mean  between the bona fide bid and asked  prices per
share of Common  Stock as so quoted  for such date on  Nasdaq,  or if none,  the
average of the means  between such bid and asked  prices on the nearest  trading
date before and the nearest  trading date after the date as of which fair market
value is to be determined, if both such dates are within a reasonable period. If
the fair market value of the Common Stock cannot be  determined on the basis set
forth above,  the Committee  shall in good faith determine the fair market value
of the Common Stock as of such date.

                  Following receipt of the notice and payment referred to above,
the Company  shall issue and  deliver to Optionee a stock  certificate  or stock
certificates  evidencing  the  Purchased  Shares;  provided,  however,  that the
Company  shall not be  obligated  to issue a fraction or fractions of a share of
its Common Stock, and may pay to Optionee,  in cash or by check, the fair market
value of any fraction or fractions of a share exercised by Optionee,  which fair
market value shall be determined as set forth in the preceding paragraph.

         5.       Termination of Services.

                  (a) If Optionee ceases to be a Director of the Company for any
reason other than  resignation,  removal for cause,  or death,  any  outstanding
portion of this Option held by Optionee  shall be  exercisable  by Optionee (but
only if and to the extent  exercisable by Optionee  immediately prior to ceasing
to be a  Director)  at any time prior to the  expiration  date of this Option or
within three years after the date Optionee ceases to be a Director, whichever is
the shorter period;

                  (b) If,  during  his or her  term  of  office  as a  Director,
Optionee  resigns  from the Board or is  removed  from  office  for  cause,  any
outstanding  portion of this Option held by Optionee which is not exercisable by
Optionee  immediately  prior to resignation or removal shall terminate as of the
date of resignation or removal,  and any outstanding portion of this Option held
by Optionee which is exercisable by Optionee immediately prior to resignation or
removal shall, to the extent then exercisable, be exercisable by Optionee at any
time prior to the  expiration  date of this Option or within  three months after
the date of resignation or removal of Optionee, whichever is the shorter period;

<PAGE>

                  (c)  Following  the  death of  Optionee  during  service  as a
Director of the Company, any outstanding portion of this Option held by Optionee
at the time of death (whether or not exercisable by Optionee  immediately  prior
to death) shall be  exercisable in full, and without regard to the provisions of
the  Exercise  Schedule,  by the  person  entitled  to do so  under  the will of
Optionee,  or, if Optionee shall fail to make  testamentary  disposition of this
Option or shall die intestate,  by the legal  representative  of Optionee at any
time prior to the expiration date of this Option or within three years after the
date of death of Optionee, whichever is the shorter period;

                  (d)  Following  the death of  Optionee  after  ceasing to be a
Director  and during a period when this Option is  exercisable  under clause (i)
above,  this Option shall be exercisable by such person  entitled to do so under
the will of  Optionee  or by such legal  representative  at any time  during the
shorter of the  following  two periods:  (A) until the  expiration  date of this
Option or (B) until three years after  Optionee  ceased  being a Director or one
year after the date of death of Optionee (whichever is longer); and

                  (e)  Following  the death of  Optionee  after  ceasing to be a
Director and during a period when this Option is  exercisable  under clause (ii)
above,  this  Option  shall,  to the extent  exercisable  on the date the person
ceased to be a Director,  be exercisable by such person  entitled to do so under
the will of  Optionee or by such legal  representative  at any time prior to the
expiration  date of this  Option  or  within  one year  after the date of death,
whichever is the shorter period.

         6.       Restrictions on Purchased Shares.

                  None of the  Purchased  Shares shall be  transferred  (with or
without consideration),  sold, offered for sale, assigned, pledged, hypothecated
or  otherwise  disposed  of (each a  "Transfer")  and the  Company  shall not be
required to register any such Transfer and the Company may instruct its transfer
agent not to register any such  Transfer,  unless and until all of the following
events shall have occurred:

                  (a) the Purchased  Shares are  Transferred  pursuant to and in
conformity  with an effective  registration  statement filed with the Securities
and Exchange  Commission  (the  "Commission")  pursuant to the Securities Act of
1933, as amended (the "Act"), and any applicable securities laws of any state of
the United States, or there exists a valid exemption from registration under the
Act and compliance with all relevant state securities laws; and

                  (b)  Optionee  has,  prior to the  Transfer of such  Purchased
Shares,  provided all  relevant  information  to Company's  counsel so that upon
Company's  request,  Company's  counsel is able to, and  actually  prepares  and
delivers to the Company a written opinion that the proposed  Transfer (i) (x) is
pursuant to a  registration  statement  which has been filed with the Commission
and is then effective,  or (y) is exempt from registration under the Act as then
in effect, and the Rules and Regulations of the Commission thereunder;  and (ii)
is either qualified or registered

<PAGE>

under any applicable state securities laws, or exempt from such qualification or
registration.  The Company  shall bear all  reasonable  costs of preparing  such
opinion.

                  Any  attempted  Transfer  which  is not in full  compliance
with this Section 6 shall be null and void ab initio, and of no force or effect.

         7.       Adjustments upon Recapitalization.

                  (a) Subject to the  provisions  of Section 7(b), if any change
is  made  in  the  Common  Stock  subject  to  the  Option  without  receipt  of
consideration  by the Company (through  merger,  consolidation,  reorganization,
recapitalization,  reincorporation,  stock dividend,  dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange of
shares,  change in corporate  structure or other  transaction  not involving the
receipt  of  consideration  by the  Company)  the Option  will be  appropriately
adjusted in the  class(es)  and maximum  number of shares  subject to the Option
pursuant to Section 1, and the outstanding Option will be appropriately adjusted
in the  class(es)  and number of shares and price per share of stock  subject to
such outstanding  Option.  Such adjustments shall be made by the Committee,  the
determination of which shall be final,  binding and conclusive.  (The conversion
of any  convertible  securities  of  the  Company  shall  not  be  treated  as a
"transaction of not involving the receipt of consideration by the Company".)

                  (b) Notwithstanding any other provision contained in the Plan,
in case any  "Paragraph 7 Event"  occurs all  outstanding  stock  options  shall
become immediately and fully exercisable whether or not otherwise exercisable by
their terms.

                  (c) For purposes of this  Paragraph 7, a specified  percentage
of "Voting  Power" of a company  shall mean such number of the Voting  Shares as
shall enable the holders  thereof to cast such percentage of all the votes which
could be cast in an annual election of directors  (without  consideration of the
rights of any class of stock other than the common stock of the company to elect
directors  by a  separate  class  vote);  and  "Voting  Shares"  shall  mean all
securities  of a company  entitling  the  holders  thereof  to vote in an annual
election of directors (without consideration of the rights of any class of stock
other than the common  stock of the  company  to elect  directors  by a separate
class of vote).

                  (d) A  "Paragraph  7 Event" shall mean the date upon which the
stockholders  of the  Company  shall  approve  a  merger,  consolidation,  share
exchange,  division or sale or other  disposition  of assets of the Company as a
result  of which  the  stockholders  of the  Company  immediately  prior to such
transaction shall not hold, directly or indirectly,  immediately  following such
transaction  a majority  of the  Voting  Power of (i) in the case of a merger or
consolidation,  the  surviving or resulting  corporation,  (ii) in the case of a
share exchange,  the acquiring corporation or (iii) in the case of a division or
a sale or other  disposition of assets,  each surviving,  resulting or acquiring
corporation which, immediately following the transaction, holds more than 10% of
the consolidated assets of the Company immediately prior to the transaction.

<PAGE>

         8.       No Rights as Director.

                  Nothing in this Agreement shall confer any right to any person
to continue  as a Director  of the  Company,  or  interfere  in any way with the
rights of the  stockholders of the Company or the Board of Directors to elect or
remove Directors.

         9.       Waiver of Rights to Purchase Stock.

                  By signing this Option  Agreement,  Optionee  acknowledges and
agrees that  neither  the  Company  nor any other  person or entity is under any
obligation to sell or transfer to Optionee any option or equity  security of the
Company,  other  than the shares of Common  Stock  subject to the Option and any
other right or option to purchase  Common Stock which was previously  granted in
writing to Optionee by the Committee. By signing this Option Agreement, Optionee
specifically waives all rights which he or she may have had prior to the date of
this Option Agreement to receive any option or equity security of the Company.

         10.      Investment Intent.

                  Optionee represents and agrees that if he or she exercises the
Option in whole or in part,  and if at the time of such exercise the Plan and\or
the  Purchased  Shares  have not been  registered  under the Act, he or she will
acquire the Shares upon such exercise for the purpose of investment and not with
a view to the distribution of such Shares issued upon their conversion, and that
upon each exercise of the Option he or she will furnish to the Company a written
statement to such effect.

         11.      Legend on Stock Certificates.

                  Optionee  agrees  that  all   certificates   representing  the
Purchased  Shares  will be  subject  to such  stock  transfer  orders  and other
restrictions  (if  any) as the  Company  may deem  advisable  under  the  rules,
regulations and other  requirements  of the Commission,  any stock exchange upon
which the Common Stock of the Company is then listed and any applicable  federal
or state  securities  laws,  and the Company may cause a legend or legends to be
put on such certificates to make appropriate reference to such restrictions.

         12.      No Rights as Shareholder.

                  Except as  provided  in  Section 7 of this  Option  Agreement,
Optionee shall have no rights as a shareholder  with respect to the Shares until
the  date  of  the  issuance  to  Optionee  of  a  stock  certificate  or  stock
certificates  evidencing such Shares.  Except as may be provided in Section 7 of
this Option  Agreement,  no adjustment shall be made for dividends  (ordinary or
extraordinary,  whether in cash,  securities or other property) or distributions
or other  rights  for which  the  record  date is prior to the date  such  stock
certificate is issued.

<PAGE>

         13.      Modification.

                  The Committee (or a committee thereof, excluding the Optionee)
may modify, extend or renew the Option or accept the surrender of, and authorize
the grant of a new  option in  substitution  for,  the Option (to the extent not
previously  exercised).  No  modification  of the  Option  shall be made  which,
without  the  consent  of  Optionee,  would  alter or impair  any  rights of the
Optionee under the Option.

         14.      Withholding.

                  The Company  shall be  entitled  to require as a condition  of
delivery of any  Purchased  Shares upon exercise of any Option that the Optionee
agree  to  remit,  at the time of such  delivery  or at such  later  date as the
Company may determine,  an amount  sufficient to satisfy all federal,  state and
local withholding tax requirements relating thereto, and Optionee agrees to take
such  other  action  required  by  the  Company  to  satisfy  such   withholding
requirements.

         15.      Character of Option.

                  The Option is not intended to qualify as an  "incentive  stock
option" as that term is defined in Section 422 of the Code.

         16.      General Provisions.

                  (a)  Further  Assurances.  Optionee  shall  promptly  take all
actions and execute all  documents  requested  by the Company  which the Company
deems to be  reasonably  necessary  to  effectuate  the terms and intent of this
Option Agreement.

                  (b)  Notices.  All  notices,   requests,   demands  and  other
communications  under this  Option  Agreement  shall be in writing  and shall be
given to the parties hereto as follows:

                                 (i)        If to the Company, to:

                                            3D Systems Corporation
                                            26081 Avenue Hall
                                            Valencia, CA 91355

                                (ii)        If to Optionee, to the address set
                                            forth in the records of the Company,

or at such other address or addresses as may have been  furnished by such either
party in writing to the other party hereto. Any such notice,  request, demand or
other communication shall be effective (i) if given by mail, 72 hours after such
communication  is deposited in the

<PAGE>

mail by first-class  certified mail, return receipt requested,  postage prepaid,
addressed as aforesaid,  or (ii) if given by any other means,  when delivered at
the address specified in this subparagraph (b).

                  (c)  Transfer  of Rights  under  this  Option  Agreement.  The
Company  may at any time  transfer  and  assign  its  rights  and  delegate  its
obligations under this Option Agreement to any other person,  corporation,  firm
or entity, including its officers,  directors and stockholders,  with or without
consideration.

                  (d) Option Non-Transferable.  Optionee may not sell, transfer,
assign or otherwise  dispose of the Option except by will or the laws of descent
and  distribution  and the Option may be  exercised  during the  lifetime of the
Optionee only by the Optionee or by his or her guardian or legal representative.

                  (e) Market Stand-Off.  In the event of an underwritten  public
offering  by the  Company  of its equity  securities  pursuant  to an  effective
registration  statement  filed  under the  Securities  Act of 1933,  as amended,
including the Company's  initial public offering.  Optionee shall not sell, make
any  short  sale  of,  loan,  hypothecate,  pledge,  grant  any  option  for the
repurchase of, or otherwise  dispose or Transfer for value or otherwise agree to
engage in any of the foregoing transactions with respect to any Shares or Common
Stock without the prior written consent of the Company or its underwriters,  for
such  period  of time from and after  the  effective  date of such  registration
statement as may be requested by the Company or such  underwriters  (the "Market
Stand-Off");  provided,  however,  that in no event shall such period exceed one
hundred-eighty  (180) days. The Market  Stand-Off shall terminate  following the
expiration of the two-year  period  immediately  following the effective date of
the Company's initial public offering.

                  (f) Successors and Assigns.  Except to the extent specifically
limited  by the terms and  provisions  of this  Option  Agreement,  this  Option
Agreement  shall be binding upon and inure to the benefit of the parties  hereto
and their respective successors, assigns, heirs and personal representatives.

                  (g) Governing Law. THIS OPTION  AGREEMENT SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA  APPLICABLE
TO CONTRACTS MADE IN, AND TO BE PERFORMED WITHIN, THAT STATE.

                  (h) The Plan.  This Option  Agreement is made  pursuant to the
Plan,  and it is  intended,  and shall be  interpreted  in a  manner,  to comply
therewith.  Any provision of this Option  Agreement  inconsistent  with the Plan
shall be superseded and governed by the Plan.

                  (i)  Miscellaneous.  Titles  and  captions  contained  in this
Option  Agreement  are inserted  for  convenience  of reference  only and do not
constitute  a part of this Option

<PAGE>

Agreement for any other purpose. Except as specifically provided herein, neither
this Option  Agreement nor any right pursuant hereto or interest herein shall be
assignable by any of the parties hereto without the prior written consent of the
other party hereto.

         The Signature Page to this Option  Agreement  consists of the last page
of the Certificate.

<PAGE>

                                   Exhibit "A"

                               NOTICE OF EXERCISE

                 (To be signed only upon exercise of the Option)

TO:      3D Systems Corporation

         The  undersigned,  the holder of the enclosed  Stock  Option  Agreement
(Non-Statutory Stock Option), hereby irrevocably elects to exercise the purchase
rights represented by the Option and to purchase  thereunder  _________ * shares
of Common Stock of 3D Systems Corporation (the "Company"), and herewith encloses
payment of $__________  and/or _________ shares of the Company's Common Stock in
full payment of the purchase price of such shares being purchased.

Dated:
      -----------

                                    -------------------------------------------
                                    (Signature  must  conform  in all  respects
                                    to name of holder as specified on the face
                                    of the Option)

                                    -------------------------------------------
                                    (Please Print Name)

                                    -------------------------------------------
                                    (Address)

         * Insert here the number of Shares called for on the face of the Option
(or, in the case of a partial  exercise,  the number of Shares being exercised),
in either case without  making any  adjustment  for  additional  Shares or other
securities  or property  which,  pursuant to the  adjustment  provisions  of the
Option, may be deliverable upon exercise.<PAGE>

                               OPTION CERTIFICATE

                     (Incentive Stock Option for Executives)

         THIS IS TO CERTIFY that 3D Systems Corporation,  a Delaware corporation
(the  "Company"),  has granted to the employee  named below an  incentive  stock
option (the  "Option")  to purchase  shares of the  Company's  Common Stock (the
"Shares"),  under its 1996 Stock Incentive Plan (the "Plan"), and upon the terms
and conditions determined by the Compensation Committee (the "Committee") of the
Board of Directors of the Company (the "Board"), as follows:

                  Name of Employee:

                  Address of Employee:
                                              ------------------------
                                              ------------------------

                  Number of Shares:

                  Option Exercise Price:    $___________________  per share

                  Date of Grant:            _________________ ___, ______

                  Option Expiration Date:   _________________ ___, 200_

         Exercise Schedule:  The Option shall become exercisable with respect to
25% of the number of shares  subject to this  Option  (rounded up or down to the
nearest  whole  number) on each of the first four  anniversaries  of the Date of
Grant.  Installments shall be cumulative,  and the Option may be exercised as to
any and all shares of Common Stock covered by an  installment  at any time after
the installment  becomes  exercisable and prior to the expiration of termination
of the Option.

         Summary of Other  Terms:  This  Option is  defined in the Stock  Option
Agreement (Incentive Stock Option) (the "Option Agreement") which is attached to
this  Option  Certificate  (the  "Certificate")  as  Annex I.  This  Certificate
summarizes   certain  of  the  provisions  of  the  Option  Agreement  for  your
information,  but is not  complete.  Your  rights  are  governed  by the  Option
Agreement, not by this summary. The Company strongly suggests that you carefully
review the full Option Agreement prior to signing this Certificate or exercising
the Option.

         Among the terms of the Option Agreement are the following:

         Termination  of Employment:  While the Option  terminates on the Option
Expiration  Date, it will  terminate  earlier if you cease to be employed by the
Company or the direct or indirect  subsidiary  of the Company  with whom you are
employed  (transfer  of  employment  from one  subsidiary  to  another  will not
constitute termination of employment). If your

<PAGE>

employment ends due to death,  the Option  terminates  eighteen months after the
date of death, and is exercisable  during such  eighteen-month  period as to the
portion  of the  Option  which had  vested  prior to the date of death.  If your
employment ends due to disability, the Option terminates twelve months after the
date of disability, and is exercisable during such twelve-month period as to the
portion of the Option which had vested prior to the date of disability.  If your
employment  ends  primarily  as a result of an act of  misconduct  described  in
Section 4(g) of the Plan, or during the period when your rights under the Option
have been  suspended by the Company  pursuant to that  Section,  the Option will
terminate  immediately.  In all other cases,  including  retirement,  the Option
terminates  ninety  days after the date of  termination  of  employment,  and is
exercisable  during such time  period as to the portion of the Option  which had
vested  prior to the date of  termination  of  employment.  See Section 5 of the
attached Option Agreement.

         Transfer:   The  Option  is  personal  to  you,  and  cannot  be  sold,
transferred,  assigned or otherwise disposed of to any other person, except upon
your death. See Section 13(d) of the attached Option Agreement.

         Exercise:  You can exercise the Option  (while it is  exercisable),  in
whole or in part, by delivering to the Company a Notice of Exercise identical to
Exhibit "A"  attached  to the Option  Agreement,  accompanied  by payment of, or
provision  pursuant to the Option  Agreement  for the  payment of, the  Exercise
Price for the Shares to be  purchased.  The  Company  may  require you to submit
certain  written  reassurances  to the Company  with respect to your status as a
shareholder. The Company will then issue a certificate to you for the Shares you
have purchased.  You are under no obligation to exercise the Option. See Section
4 of the attached Option Agreement.

         Reload Option:  If and to the extent that the Exercise Price is paid by
delivery  of shares of the  Company's  Common  Stock  (see  Section  4(b) of the
attached Option  Agreement),  you will  automatically be granted a new option (a
"Reload  Option") for a like number of shares,  with an exercise  price equal to
the market value of a share of Common Stock on the date of exercise,  and a term
equal  to the  term of the  Option.  See  Section  4(d) of the  attached  Option
Agreement.

         Adjustments upon Recapitalization: The Option contains provisions which
affect your rights in the event of stock splits,  stock  dividends,  mergers and
other major  corporate  reorganizations.  See Section 6 of the  attached  Option
Agreement.

         Waiver: By signing this Certificate, you will be agreeing to all of the
terms  of  the  Option  Agreement,   including  those  not  summarized  in  this
Certificate.  You will waive your rights to options or stock which may otherwise
have been promised to you. See Section 7 of the attached Option Agreement.

         Withholding:  The  Company  may  require  you to make any  arrangements
necessary  to insure  the  proper  withholding  of any  amount  of tax,  if any,
required  to be  withheld  by the

<PAGE>

Company  as a result  of the  exercise  of the  Option.  See  Section  10 of the
attached Option Agreement.

         Value of Shares:  If you are granted an Option first exercisable in any
one calendar  year to purchase  Shares valued in excess of $100,000 on the grant
date,  then for tax  purposes  the  incremental  portion of such  Shares with an
aggregate  fair  market  value  in  excess  of  $100,000  shall  be  treated  as
non-statutory  stock  options,  rather than as incentive  stock options (as that
term is  defined  in  Section  422 of the  Internal  Revenue  Code of  1986,  as
amended).

                                A G R E E M E N T

         3D Systems Corporation,  a Delaware corporation,  and the Employee each
hereby agrees to be bound by all of the terms and conditions of the Stock Option
Agreement  (Incentive  Stock  Option)  which is  attached  hereto as Annex I and
incorporated herein by this reference as if set forth in full in this document.

DATED:

                                    3D SYSTEMS CORPORATION

                                    By:

                                    Its:

                                    EMPLOYEE

                                    ______________________________________
                                    Name:

                                                                   (Please print
                                    your  name  exactly as you wish it to appear
                                    on any stock certificates issued to you upon
                                    exercise of the Option)

<PAGE>

                                     ANNEX I

                             STOCK OPTION AGREEMENT
                     (Incentive Stock Option for Executives)

         This STOCK  OPTION  AGREEMENT  (this  "Option  Agreement")  is made and
entered  into on the  execution  date of the Option  Certificate  to which it is
attached (the "Certificate"),  by and between 3D Systems Corporation, a Delaware
corporation  (the  "Company"),  and the  Officer  of the  Company  named  in the
Certificate ("Employee").

         Pursuant to the 3D Systems  Corporation  1996 Stock Incentive Plan (the
"Plan"), the Compensation  Committee (the "Committee") of the Board of Directors
of the  Company  (the  "Board")  has  authorized  the  grant to  Employee  of an
incentive  stock option to purchase  shares of the Company's  Common Stock,  par
value $0.001 per share (the "Common  Stock"),  upon the terms and subject to the
conditions set forth in this Option Agreement and in the Plan.

         The Company and Employee agree as follows:

         1.       Grant of Option.

                  The Company  hereby  grants to  Employee  the right and option
(the  "Option"),  upon the terms and subject to the conditions set forth in this
Option Agreement, to purchase all or any portion of that number of shares of the
Common Stock (the "Shares") set forth in the Certificate, at the Option exercise
price set forth in the Certificate (the "Exercise Price").

         2.       Term of Option.

                  The Option shall terminate and expire on the Option Expiration
Date set forth in the Certificate,  unless sooner terminated as provided herein.
In no event shall the Option be  exercisable  after the  expiration of ten years
from the date it was granted.

         3.       Exercise Period.

                  (a) Subject to the  provisions  of Sections 3(b) and 5 of this
Option Agreement, the Option shall become exercisable (in whole or in part) upon
and  after  the dates set  forth or  referred  to under  the  caption  "Exercise
Schedule" in the Certificate.  The installments  shall be cumulative;  i.e., the
Option may be exercised,  as to any or all Shares covered by an installment,  at
any time or times after the  installment  first  becomes  exercisable  and until
expiration or termination of the Option.

<PAGE>

                  (b) Notwithstanding anything to the contrary contained in this
Option Agreement,  the Option may not be exercised,  in whole or in part, unless
and until any then-applicable  requirements of all federal, state and local laws
and regulatory  agencies shall have been fully complied with to the satisfaction
of the Company and its  counsel.  In  addition,  if the  Company  believes  that
Employee has  committed an act of misconduct as described in Section 4(g) of the
Plan  (which  acts  of  misconduct  ("Acts  of  Misconduct")  include  an act of
embezzlement,  fraud,  nonpayment of any  obligation  owed to the Company or any
subsidiary,  breach of fiduciary  duty or deliberate  disregard of the Company's
rules  resulting  in loss,  damage or injury to the  Company,  any  unauthorized
disclosure  of trade secrets or  confidential  information  of the Company,  any
conduct  constituting unfair  competition,  or the inducement of any customer of
the Company to breach a contract with the Company),  the Company may suspend the
Employee's  rights  under the  Option  pending a  determination  by the Board of
Directors,  which shall have the right,  as therein  provided,  to terminate the
Option.

         4.       Exercise of Option.

                  There is no obligation to exercise the Option,  in whole or in
part. The Option may be exercised,  in whole or in part, only by delivery to the
Company of:

                  (a) written notice of exercise in form and substance identical
to Exhibit "A" attached to this Option Agreement stating the number of shares of
Common Stock then being purchased (the "Purchased Shares");

                  (b) the Exercise Price for each Purchased  Share shall be paid
in full upon  exercise  and shall be  payable in cash in United  States  dollars
(including check, bank draft or money order); provided, however, that in lieu of
cash the person  exercising the Option may pay the Exercise Price in whole or in
part by  delivering  to the  Company  shares of the Common  Stock  having a fair
market  value on the date of exercise of the Option,  determined  as provided in
Section 4(c), equal to the Exercise Price for the Shares being purchased; except
that (i) any portion of the Exercise  Price  representing  a fraction of a Share
shall in any event be paid in cash and (ii) no shares of the Common  Stock which
have been held for less than six  months  may be  delivered  in  payment  of the
Exercise Price of an Option. Delivery of shares may also be accomplished through
the effective transfer to the Company of shares held by a broker or other agent.
The Company will also cooperate with any person who  participates  in a cashless
exercise  program  of a broker  or other  agent  under  which all or part of the
shares received upon exercise of the Option are sold through the broker or other
agent or under  which the  broker or other  agent  makes a loan to such  person.
Notwithstanding the foregoing, the exercise of the Option shall not be deemed to
occur and no shares of Common Stock will be issued by the Company upon  exercise
of the Option  until the Company has received  payment of the Exercise  Price in
full.  The date of exercise of an Option shall be  determined  under  procedures
established  by the  Committee.  Payment of the Exercise Price with shares shall
not  increase the number of shares of the Common Stock which may be issued under
the Plan.

                  (c) If payment is made,  in whole or in part,  by  transfer to
the Corporation of issued and outstanding  shares of Common Stock,  the value of
such shares shall be the mean between the following prices,  as applicable,  for
the date as of which fair market value is to be determined as

<PAGE>

quoted in The Wall Street Journal (or in such other reliable  publication as the
Company, in its discretion, may determine to rely upon): (i) if the Common Stock
is listed on a United States securities  exchange,  the highest and lowest sales
prices per share of Common Stock for such date on the  principal  United  States
securities  exchange on which the Common Stock is listed,  or (ii) if the Common
Stock is not listed on any such  exchange,  the highest and lowest  sales prices
per share of the Common Stock for such date on the Nasdaq National Market or any
successor system then in use. If there are no such sale price quotations for the
date as of which fair market value is to be  determined  but there are such sale
price  quotations  within a  reasonable  period both before and after such date,
then fair  market  value shall be  determined  by taking an average of the means
between the highest and lowest  sales prices per share of the Common Stock as so
quoted on the  nearest  date  before and the  nearest  date after the date as of
which fair  market  value is to be  determined.  If there are no such sale price
quotations on or within a reasonable period both before and after the date as of
which fair  market  value is to be  determined,  then fair  market  value of the
Common  Stock shall be the mean  between the bona fide bid and asked  prices per
share of Common  Stock as so quoted  for such date on  Nasdaq,  or if none,  the
average of the means  between such bid and asked  prices on the nearest  trading
date before and the nearest  trading date after the date as of which fair market
value is to be determined, if both such dates are within a reasonable period. If
the fair market value of the Common Stock cannot be  determined on the basis set
forth above,  the Committee  shall in good faith determine the fair market value
of the Common Stock as of such date.

                  (d) If Employee  delivers shares of Common Stock in payment of
the  Exercise  Price of the Option,  as provided in  Paragraph  4(b) above,  the
Employee shall be  automatically  granted the  additional  right and option (the
"Reload  Option")  to  purchase  all or any  portion of that number of shares of
Common  Stock equal to the number of shares of Common  Stock so  delivered  upon
exercise of the Option.  Each Reload Option shall (i) have a per Share  Exercise
Price equal to the fair market value of the Common Stock on the date of exercise
of the  Option to which such  Reload  Option  relates,  determined  pursuant  to
Section  4(c) of this  Option  Agreement;  (ii) have a term no  longer  than the
remaining term of the Option at the time of exercise; (iii)become exercisable in
full from and after that date which is six months  following  its date of grant;
and (iv)  otherwise  have terms and  conditions  identical  to the  Option.  The
Company  shall  promptly  following  the grant of a Reload  Option  prepare  and
deliver to Employee a written option agreement  memorializing  the grant of such
Reload Option; but the failure to prepare and deliver such  documentation  shall
not affect the continuing validity and enforceability of such Reload Option.

         5.       Termination of Employment.

                  (a) If Employee  shall cease to be an employee of the Company,
or any direct or indirect  subsidiary of the Company,  (other than as the result
of the transfer of  employment of Employee to another  corporation  which is the
Company,  or any direct or indirect  subsidiary  of the  Company) for any reason
other than death or permanent disability (a "Terminating Event"), Employee shall
have the right, subject to the provisions of Section 5(b) below, to exercise the
Option at any time following such Terminating  Event until the earliest to occur
of (x) 90  days  following  the  date  of  such  Terminating  Event  and (y) the
expiration  of the term of this  Option as set forth in Section 2 of this Option
Agreement. The Option may be exercised following a Terminating Event only to the
extent  exercisable  as of the  date of the  Terminating  Event.  To the  extent
unexercised  at the end of the  period

<PAGE>

referred to above,  the Option shall terminate.  The Committee,  in its sole and
absolute discretion,  shall determine whether authorized leaves of absence shall
constitute termination of employment for purposes of this Option Agreement.

                  (b)  Notwithstanding the provisions of Section 5(a), above, if
Employee shall cease to be an employee of the Company, or any direct or indirect
subsidiary  of the  Company  (other  than  as the  result  of  the  transfer  of
employment  of  Employee to another  corporation  which is the  Company,  or any
direct or indirect  subsidiary of the Company)  primarily as a result of any Act
of  Misconduct  described in Section 4(g) of the Plan, or during the period when
Employee's rights under this Option Agreement have been suspended by the Company
pursuant to Section 4(g) of the Plan,  Employee's  rights to exercise the Option
shall terminate immediately.

                  (c)  If,  by  reason  of  death  or   disability  (a  "Special
Terminating  Event"),  Employee shall cease to be an employee the Company or any
direct or indirect  subsidiary  of the Company  (other than as the result of the
transfer of employment of Employee to another  corporation which is the Company,
or any direct or indirect subsidiary of the Company), then Employee,  Employee's
executors  or  administrators  or any  person or  persons  acquiring  the Option
directly  from  Employee  by  bequest  or  inheritance,  shall have the right to
exercise the Option (i) in the event of  Employee's  disability,  within  twelve
months  following  the date of such Special  Terminating  Event,  or (ii) in the
event of Employee's  death,  within eighteen  months  following the date of such
Special  Terminating  Event.  The Option may be  exercised  following  a Special
Terminating  Event only to the  extent  exercisable  at the date of the  Special
Terminating  Event. To the extent  unexercised at the end of the period referred
to above, the Option shall terminate.

                  (d) For purposes of this Option Agreement,  "disability" shall
mean total and  permanent  disability  as defined  in  Section  22(e)(3)  of the
Internal  Revenue Code of 1986, as amended (the "Code").  Employee  shall not be
considered  permanently disabled unless he furnishes proof of such disability in
such form and manner,  and at such times, as the Committee may from time to time
require.

         6.       Adjustments upon Recapitalization.

                  In the event of any  change in the  outstanding  shares of the
Common Stock or other securities then subject to the Plan by reason of any stock
split,   reverse  stock  split,   stock  dividend,   recapitalization,   merger,
consolidation,  combination  or  exchange of shares or other  similar  corporate
change,  or if the  outstanding  securities  of the class  then  subject to this
Agreement are exchanged for or converted into cash, property or a different kind
of securities,  or if cash, property or securities are distributed in respect of
such outstanding securities (other than a regular cash divided) then, unless the
terms of such transaction shall otherwise  provide,  such equitable  adjustments
shall be made by the Board, or the Committee, in the Option (including,  without
limitation,  appropriate and proportionate adjustments to the number and type of
shares  or other  securities  or cash or  other  property  that may be  acquired
pursuant to exercise of the Option);  and any such adjustments made by the Board
or the  Committee  shall  be  final,  binding  and  conclusive  for  any and all
purposes.

<PAGE>

         7.       Waiver of Rights to Purchase Stock.

                  By signing this Option  Agreement,  Employee  acknowledges and
agrees that  neither  the  Company  nor any other  person or entity is under any
obligation to sell or transfer to Employee any option or equity  security of the
Company,  other  than the shares of Common  Stock  subject to the Option and any
other right or option to purchase  Common Stock which was previously  granted in
writing to Employee by the  Committee  (or the  Board).  By signing  this Option
Agreement,  Employee specifically waives all rights which he or she may have had
prior to the date of this Option Agreement (other than any other right or option
to purchase Common Stock which was previously  granted in writing to Employee by
the  Committee  or the Board) to receive  any option or equity  security  of the
Company.

         8.       No Rights as Shareholder.

                  Except as  provided  in  Section 6 of this  Option  Agreement,
Employee shall have no rights as a shareholder  with respect to the Shares until
the  date  of  the  issuance  to  Employee  of  a  stock  certificate  or  stock
certificates  evidencing such Shares.  Except as may be provided in Section 6 of
this Option  Agreement,  no adjustment shall be made for dividends  (ordinary or
extraordinary,  whether in cash,  securities or other property) or distributions
or other  rights  for which  the  record  date is prior to the date  such  stock
certificate is issued.

         9.       Modification.

                  Subject to the terms and conditions and within the limitations
of the Plan, the Committee (or the Board) may modify, extend or renew the Option
or  accept  the  surrender  of,  and  authorize  the  grant of a new  option  in
substitution  for,  the  Option (to the extent  not  previously  exercised).  No
modification of the Option shall be made which, without the consent of Employee,
would  cause the Option to fail to continue  to qualify as an  "incentive  stock
option"  within  Section  422 of the Code or would alter or impair any rights of
the Employee under the Option.

         10.      Disqualifying Disposition; Withholding.

                  (a) Employee agrees that should he or she make a "disposition"
(as defined in Section 424(c) of the Code) of all or any of the Purchased Shares
within  two years  from the date of the grant of the  Option or within  one year
after the issuance of such Purchased Shares, he or she shall immediately  advise
the Company in writing as to the  occurrence of the sale and the price  realized
upon the sale of such  Purchased  Shares.  Employee  agrees that he or she shall
maintain all Purchased  Shares in his or her name so long as he or she maintains
beneficial ownership of such Shares.

                  (b) The Company shall be entitled to require as a condition of
delivery of any  Purchased  Shares upon exercise of any Option that the Employee
agree  to  remit,  at the time of such  delivery  or at such  later  date as the
Company may determine,  an amount  sufficient to satisfy all

<PAGE>

federal,  state and local  withholding tax requirements  relating  thereto,  and
Employee  agrees to take such other  action  required  by the Company to satisfy
such withholding requirements.

         11.      Services of Option Holder.

                  In consideration for the grant of the Option,  Employee agrees
to remain in the  employ  of,  and shall  continue  to render  services  to, the
Company or any direct or indirect  subsidiary  of the Company,  as the Committee
may from  time to time  direct,  for a period  of one year from the date of this
Option  Agreement.  This  provision  shall not  obligate  the  Company,  or such
subsidiary,  to continue to employ, or utilize the services of, Employee for any
period whatsoever.  The sole remedy to the Company should Employee breach his or
her obligations  under this Section 11 shall be to cancel this Option  Agreement
and the Option  granted  under this Option  Agreement.  For the purposes of this
Option  Agreement,  the term  "subsidiary"  shall  mean any  present  or  future
corporation which would be a "subsidiary corporation" of the Company, as defined
in Section 424 of the Code.

         12.      Character of Option.

                  The  Option is  intended  to qualify  as an  "incentive  stock
option" as that term is defined in Section 422 of the Code.

         13.      General Provisions.

                  (a)  Further  Assurances.  Employee  shall  promptly  take all
actions and execute all  documents  requested  by the Company  which the Company
deems to be  reasonably  necessary  to  effectuate  the terms and intent of this
Option Agreement.

                  (b)  Notices.  All  notices,   requests,   demands  and  other
communications  under this  Option  Agreement  shall be in writing  and shall be
given to the parties hereto as follows:

                            (i)     If to the Company, to:

                                    3D Systems Corporation
                                    26081 Avenue Hall
                                    Valencia, CA  91355
                                    Attention: General Counsel

                            (ii)    If to Employee,  to the address set
                                    forth in the records of the Company,

or at such other address or addresses as may have been  furnished by such either
party in writing to the other party hereto. Any such notice,  request, demand or
other communication shall be effective (i) if

<PAGE>

given by mail,  72 hours after such  communication  is  deposited in the mail by
first-class certified mail, return receipt requested, postage prepaid, addressed
as aforesaid; or (ii) if given by any other means, when delivered at the address
specified in this subparagraph (b).

                  (c)  Transfer  of Rights  under  this  Option  Agreement.  The
Company  may at any time  transfer  and  assign  its  rights  and  delegate  its
obligations under this Option Agreement to any other person,  corporation,  firm
or entity, including its officers,  directors and stockholders,  with or without
consideration.

                  (d) Option Non-Transferable.  Employee may not sell, transfer,
assign or otherwise  dispose of the Option except by will or the laws of descent
and  distribution,  and Options may be exercised during the lifetime of Employee
only by Employee or by his or her guardian or legal representative.

                  (e) Market Stand-Off.  In the event of an underwritten  public
offering  by the  Company  of its equity  securities  pursuant  to an  effective
registration  statement  filed  under the  Securities  Act of 1933,  as amended,
Employee  shall not sell,  make any short sale of,  loan,  hypothecate,  pledge,
grant any option for the  repurchase  of, or  otherwise  dispose or transfer for
value,  or otherwise agree to engage in any of the foregoing  transactions  with
respect to any shares of Common Stock without the prior  written  consent of the
Company  or its  underwriters,  for  such  period  of time  from and  after  the
effective date of such registration statement as may be requested by the Company
or such underwriters (the "Market  Stand-Off");  provided,  however,  that in no
event shall such period exceed 180 days.

                  (f) Successors and Assigns.  Except to the extent specifically
limited  by the terms and  provisions  of this  Option  Agreement,  this  Option
Agreement  shall be binding upon and inure to the benefit of the parties  hereto
and their respective successors, assigns, heirs and personal representatives.

                  (g) Governing Law. THIS OPTION  AGREEMENT SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA  APPLICABLE
TO CONTRACTS MADE IN, AND TO BE PERFORMED SOLELY WITHIN, THAT STATE.

                  (h) The Plan.  This Option  Agreement is made  pursuant to the
Plan,  and it is  intended,  and shall be  interpreted  in a  manner,  to comply
therewith.  Any provision of this Option  Agreement  inconsistent  with the Plan
shall be superseded and governed by the Plan.

<PAGE>

                  (i)  Miscellaneous.  Titles  and  captions  contained  in this
Option  Agreement  are inserted  for  convenience  of reference  only and do not
constitute a part of this Option Agreement for any other purpose.

                  The Signature  Page to this Option  Agreement  consists of the
last page of the Certificate.

<PAGE>

                                   Exhibit "A"

                               NOTICE OF EXERCISE

                 (To be signed only upon exercise of the Option)

TO:      3D Systems Corporation

         The  undersigned,  the holder of the enclosed  Stock  Option  Agreement
(Incentive  Stock Option),  hereby  irrevocably  elects to exercise the purchase
rights  represented by the Option and to purchase  thereunder  ______* shares of
Common Stock of 3D Systems  Corporation (the "Company"),  and herewith  encloses
payment of $__________  and/or _________ shares of the Company's Common Stock in
full payment of the purchase price of such shares being purchased.

Dated: _____________________

                                      ------------------------------------------
                                      (Signature must conform in all respects
                                      to name of holder as specified on the face
                                      of the Option)
                                      ------------------------------------------
                                      (Please Print Name)

                                      ------------------------------------------
                                      (Address)

                                      ------------------------------------------

         * Insert here the number of shares called for on the face of the Option
(or, in the case of a partial  exercise,  the number of shares being exercised),
in either case without making any adjustment for additional  Common Stock of the
Company,  other  securities  or  property  which,  pursuant  to  the  adjustment
provisions of the Option, may be deliverable upon exercise.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}]]