
                                                                     EXHIBIT 4.1

                            INVESTOR RIGHTS AGREEMENT

      THIS INVESTOR  RIGHTS  AGREEMENT (the  "AGREEMENT")  is entered into as of
December 9, 2005, by and among EarthShell  Corporation,  a Delaware  corporation
(the  "COMPANY")  and the  purchasers  of the  Company's  Common Stock  ("COMMON
STOCK") set forth on Schedule 1 of that  certain  Letter  Agreement of even date
herewith (the "LETTER  AGREEMENT")  and Schedule 1 hereto and the grantees under
the Warrant  Agreements  (the "WARRANT  AGREEMENTS")  issued as set forth in the
Letter  Agreement.  The  purchasers  of the Common Stock and grantees  under the
Warrant  Agreements shall be referred to hereinafter as the "INVESTORS" and each
individually as an "INVESTOR."

                             PRELIMINARY STATEMENTS

      A. As of the date  hereof,  the  Company  has sold and issued Two  Hundred
Sixty-Six  Thousand  Six-Hundred  Sixty-Seven  (266,667)  shares of Common Stock
pursuant to the Letter  Agreement and the related Stock  Purchase  Agreement and
One Million Thirty-Three Thousand Three Hundred Thirty-Three  (1,033,333) shares
of its Common Stock  pursuant to the Letter  Agreement  and the related  Warrant
Agreements, as set forth in the Letter Agreement.

      B. As a condition of entering  into the Letter  Agreement,  the  Investors
have requested that the Company extend to them registration  rights as set forth
below.

                                    AGREEMENT

      NOW, THEREFORE, in consideration of the mutual promises,  representations,
warranties,  covenants  and  conditions  set forth in this  Agreement and in the
Letter  Agreement and for other good,  valuable and binding  consideration,  the
parties hereto, intending to be legally bound hereby, mutually agree as follows:

I. GENERAL


      1.1 DEFINITIONS.  As used in this Agreement the following terms shall have
the following respective meanings:

      "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended.

      "FORM S-3" means  such form under the  Securities  Act as in effect on the
date  hereof  or any  successor  registration  form  under  the  Securities  Act
subsequently  adopted by the SEC which  permits  inclusion or  incorporation  of
substantial  information  by reference to other  documents  filed by the Company
with the SEC.

      "HOLDER"  means any person owning of record  Registrable  Securities  that
have not been sold to the public or any  assignee of record of such  Registrable
Securities in accordance with Section 2.9 hereof.

      "REGISTER,"  "REGISTERED,"  and  "REGISTRATION"  refer  to a  registration
effected by preparing and filing a registration statement in compliance with the
Securities  Act,  and the  declaration  or  ordering  of  effectiveness  of such
registration statement or document.


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      "REGISTRABLE  SECURITIES"  means (a) Common Stock of the Company issued to
Investors pursuant to the Letter Agreement,  Stock Purchase Agreement or Warrant
Agreements;  and (b) any Common Stock of the Company issued as (or issuable upon
the  exercise  of any  warrant,  right or other  security  which is issued as) a
dividend  or other  distribution  with  respect  to,  or in  exchange  for or in
replacement of, such above-described securities.  Notwithstanding the foregoing,
Registrable Securities shall not include any securities eligible to be sold by a
person to the public pursuant to a registration  statement or Rule 144 under the
Securities Act or sold in a private transaction in which the transferor's rights
under Section 2 of this Agreement are not assigned.

      "REGISTRATION EXPENSES" shall mean all expenses incurred by the Company in
complying with Sections 2.1, 2.2 and 2.3 hereof, including,  without limitation,
all registration and filing fees,  printing expenses,  fees and disbursements of
counsel for the Company,  reasonable fees and  disbursements of a single special
counsel  for the  Holders,  blue sky fees and  expenses  and the  expense of any
special audits incident to or required by any such  registration  (including the
compensation  of regular  employees  of the  Company  which shall be paid in any
event by the Company).

      "SEC" or "COMMISSION" means the Securities and Exchange Commission.

      "SECURITIES ACT" means the Securities Act of 1933, as amended.

      "SELLING   EXPENSES"   means  all   underwriting   discounts  and  selling
commissions applicable to the sale.

      "SHARES"  means the  Company's  Common Stock issued  pursuant to the Stock
Purchase  Agreement or Warrant  Agreements  and held by the Investors  listed on
schedule 1 hereto and their permitted assigns.

II. REGISTRATION

      2.1 DEMAND REGISTRATION.

            (a) Subject to the  conditions  hereof and  applicable  law, rule or
regulation,  if the Company shall receive a written  request from the Holders of
twenty-five  percent of the Registrable  Securities (the  "INITIATING  HOLDERS")
that the Company file a registration statement under the Securities Act covering
the registration of at least twenty-five  percent of the Registrable  Securities
(a "QUALIFIED PUBLIC OFFERING"), then the Company shall, within thirty (30) days
of the receipt thereof,  give written notice of such request to all Holders, and
subject to the  limitations of this Section 2.1, use its best efforts to effect,
as soon  as  practicable,  the  registration  under  the  Securities  Act of all
Registrable  Securities that the Holders request within ten days of the delivery
of the Company's notice to be registered.


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<PAGE>

            (b) If the Initiating  Holders intend to distribute the  Registrable
Securities  covered by their request by means of an underwriting,  they shall so
advise the Company as a part of their  request made pursuant to this Section 2.1
or any  request  pursuant  to Section 2.3 and the  Company  shall  include  such
information  in the  written  notice  referred  to in Section  2.1(a) or Section
2.3(a),  as  applicable.  In such event,  the right of any Holder to include its
Registrable  Securities  in such  registration  shall be  conditioned  upon such
Holder's  participation in such  underwriting and the inclusion of such Holder's
Registrable  Securities in the underwriting to the extent provided  herein.  All
Holders proposing to distribute their securities through such underwriting shall
enter into an  underwriting  agreement in customary form with the underwriter or
underwriters  selected  for such  underwriting  by a majority in interest of the
Initiating  Holders  (which  underwriter  or  underwriters  shall be  reasonably
acceptable to the Company).  Notwithstanding any other provision of this Section
2.1 or Section  2.3,  if the  underwriter  advises the  Company  that  marketing
factors  require a limitation  of the number of  securities  to be  underwritten
(including Registrable  Securities) then the Company shall so advise all Holders
of Registrable Securities which would otherwise be underwritten pursuant hereto,
and the  number of shares  that may be  included  in the  underwriting  shall be
allocated  to the  Holders of such  Registrable  Securities  on a pro rata basis
based  on  the  number  of  Registrable  Securities  held  by all  such  Holders
(including the  Initiating  Holders).  Any  Registrable  Securities  excluded or
withdrawn from such underwriting shall be withdrawn from the registration.

            (c) The  Company  shall not be  required  to  effect a  registration
pursuant to this Section 2.1:

                  (i) if the Company has effected one (1) registrations pursuant
to this  Section  2.1,  and such  registrations  have been  declared  or ordered
effective; or

                  (ii) if the Initiating Holders propose to dispose of shares of
Registrable  Securities that may be immediately  registered on Form S-3 pursuant
to a request made pursuant to Section 2.3 below.

      2.2  PIGGYBACK  REGISTRATIONS.  The  Company  shall  notify all Holders of
Registrable Securities in writing at least fifteen (15) days prior to the filing
of any registration  statement under the Securities Act for purposes of a public
offering  of  securities  of  the  Company  (including,   but  not  limited  to,
registration  statements  relating to secondary  offerings of  securities of the
Company,  but excluding  registration  statements  relating to employee  benefit
plans or with respect to corporate  reorganizations  or other transactions under
Rule 145 of the Securities  Act) and will afford each such Holder an opportunity
to  include  in such  registration  statement  all or  part of such  Registrable
Securities held by such Holder,  unless the Company is otherwise prohibited from
doing so due to an agreement  outstanding as of the date hereof or by applicable
law,  rule  or  regulation.   Each  Holder  desiring  to  include  in  any  such
registration  statement all or any part of the Registrable Securities held by it
shall,  within  fifteen  (15) days  after the  above-described  notice  from the
Company, so notify the Company in writing.  Such notice shall state the intended
method of disposition of the Registrable  Securities by such Holder. If a Holder
decides not to include all of its  Registrable  Securities  in any  registration
statement  thereafter  filed by the  Company,  such  Holder  shall  nevertheless
continue  to have  the  right  to  include  any  Registrable  Securities  in any
subsequent  registration statement or registration statements as may be filed by
the Company with respect to offerings of its securities,  all upon the terms and
conditions set forth herein.


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<PAGE>

            (a)  Underwriting.  If the  registration  statement  under which the
Company gives notice under this Section 2.2 is for an underwritten offering, the
Company shall so advise the Holders of  Registrable  Securities.  In such event,
the right of any such Holder to be included in a  registration  pursuant to this
Section  2.2 shall be  conditioned  upon  such  Holder's  participation  in such
underwriting  and the inclusion of such Holder's  Registrable  Securities in the
underwriting to the extent provided herein.  All Holders proposing to distribute
their  Registrable  Securities  through  such  underwriting  shall enter into an
underwriting  agreement in customary form with the  underwriter or  underwriters
selected  for  such  underwriting  by the  Company.  Notwithstanding  any  other
provision of the  Agreement,  if the  underwriter  determines in good faith that
marketing   factors  require  a  limitation  of  the  number  of  shares  to  be
underwritten,  the number of shares  that may be  included  in the  underwriting
shall be allocated,  first, to the Company; second, to the Holders on a pro rata
basis based on the total number of Registrable  Securities  held by the Holders;
and third, to any shareholder of the Company (other than a Holder) on a pro rata
basis, unless the Company is required to effect a different allocation due to an
agreement outstanding as of the date hereof or by law or applicable law, rule or
regulation.  No such  reduction  shall  reduce the amount of  securities  of the
selling Holders included in the registration below twenty-five  percent (25%) of
the total amount of securities included in such registration, unless the Company
is required to do so due to an agreement outstanding as of the date hereof or by
law or applicable  law, rule or  regulation.  If any Holder  disapproves  of the
terms of any such  underwriting,  such Holder may elect to withdraw therefrom by
written notice to the Company and the  underwriter,  delivered at least ten (10)
business days prior to the effective  date of the  registration  statement.  Any
Registrable  Securities  excluded or withdrawn from such  underwriting  shall be
excluded  and  withdrawn  from  the  registration.  For any  Holder  which  is a
partnership or corporation,  the partners,  retired partners and shareholders of
such Holder,  or the estates and family members of any such partners and retired
partners and any trusts for the benefit of any of the foregoing  person shall be
deemed to be a single "Holder",  and any pro rata reduction with respect to such
"Holder"  shall  be  based  upon  the  aggregate   amount  of  shares   carrying
registration  rights  owned by all  entities  and  individuals  included in such
"Holder," as defined in this sentence.

            (b) Right to  Terminate  Registration.  The  Company  shall have the
right to  terminate  or withdraw  any  registration  initiated  by it under this
Section 2.2 prior to the effectiveness of such  registration  whether or not any
Holder has elected to include securities in such registration.  The Registration
Expenses  of such  withdrawn  registration  shall  be borne  by the  Company  in
accordance with Section 2.4 hereof.

      2.3 FORM S-3 REGISTRATION. Subject to the conditions hereof and applicable
law rules or regulation,  in the event the Company shall receive from any Holder
or Holders of  Registrable  Securities  a written  request or requests  that the
Company effect a registration  on Form S-3 (or any successor to Form S-3) or any
similar short-form  registration  statement with respect to all or a part of the
Registrable Securities owned by such Holder or Holders in excess of an aggregate
of hundred-thousand shares of Registrable Securities, the Company will:

            (a) promptly give written notice of the proposed  registration,  and
any related  qualification  or  compliance,  to all other Holders of Registrable
Securities; and


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<PAGE>

            (b) as soon as  practicable,  file a registration  statement on Form
S-3 and effect such  registration  as may be so requested and as would permit or
facilitate the sale and  distribution of all or such portion of such Holder's or
Holders' Registrable Securities as are specified in such request,  together with
all or such portion of the Registrable Securities of any other Holder or Holders
joining in such  request as are  specified  in a written  request  given  within
fifteen  (15) days  after  receipt  of such  written  notice  from the  Company;
provided,  however,  that the Company  shall not be obligated to effect any such
registration,  qualification or compliance  pursuant to this Section 2.3 if Form
S-3 (or any successor or similar form) is not available for such offering by the
Holders.

      2.4  EXPENSES  OF  REGISTRATION.  All  Registration  Expenses  incurred in
connection  with any  registration,  qualification  or  compliance  pursuant  to
Section 2.1 or any registration under Section 2.2 or Section 2.3 herein shall be
borne by the  Company.  All Selling  Expenses  incurred in  connection  with any
registrations  hereunder,  shall be borne by the  holders of the  securities  so
registered pro rata on the basis of the number of shares so registered.

      2.5  OBLIGATIONS  OF  THE  COMPANY.   Whenever   required  to  effect  the
registration of any Registrable Securities,  the Company shall, as expeditiously
as reasonably possible:

            (a)  Prepare  and file with the SEC a  registration  statement  with
respect to such Registrable  Securities and use all reasonable  efforts to cause
such registration  statement to become  effective,  and, upon the request of the
Holders of a majority of the Registrable Securities registered thereunder,  keep
such registration statement effective for up to thirty (30) days or, if earlier,
until the Holder or Holders have completed the distribution related thereto. The
Company shall not be required to file, cause to become effective or maintain the
effectiveness of any registration  statement that contemplates a distribution of
securities  on a delayed  or  continuous  basis  pursuant  to Rule 415 under the
Securities Act.

            (b) Prepare and file with the SEC such amendments and supplements to
such  registration  statement and the  prospectus  used in connection  with such
registration  statement as may be necessary to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement for the period set forth in paragraph (a) above.

            (c)  Furnish to the Holders  such number of copies of a  prospectus,
including a preliminary  prospectus,  in conformity with the requirements of the
Securities Act, and such other documents as they may reasonably request in order
to facilitate the disposition of Registrable Securities owned by them.

            (d) [Intentionally omitted.]

            (e) In the event of any underwritten public offering, enter into and
perform its obligations under an underwriting  agreement, in usual and customary
form,  with  the  managing   underwriter(s)   of  such  offering.   Each  Holder
participating  in such  underwriting  shall  also  enter  into and  perform  its
obligations under such an agreement.

            (f) Notify each  Holder of  Registrable  Securities  covered by such
registration statement at any time when a prospectus relating thereto is, to its
knowledge, required to be delivered under the Securities Act of the happening of
any event as a result  of which the  prospectus  included  in such  registration
statement, as then in effect, includes an untrue statement of a material fact or
omits to state a material  fact  required to be stated  therein or  necessary to
make the  statements  therein not  misleading in the light of the  circumstances
then existing.


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<PAGE>

            (g)  Use  its  best  efforts  to  furnish,  on the  date  that  such
Registrable  Securities  are  delivered to the  underwriters  for sale,  if such
securities are being sold through underwriters, (i) an opinion, dated as of such
date,  of the  counsel  representing  the  Company  for  the  purposes  of  such
registration,  in form and substance as is customarily  given to underwriters in
an underwritten public offering, addressed to the underwriters, if any, and (ii)
a  letter  dated  as  of  such  date,  from  the  independent  certified  public
accountants  of the Company,  in form and substance as is  customarily  given by
independent  certified  public  accountants to  underwriters  in an underwritten
public offering addressed to the underwriters.

      2.6 TERMINATION OF REGISTRATION  RIGHTS.  All registration  rights granted
under this Section 2 shall  terminate  and be of no further  force and effect if
all  Registrable  Securities  held by and  issuable  to  such  Holder  (and  its
affiliates,  partners, former partners,  members and former members) may be sold
under Rule 144 during any ninety (90) day period.

      2.7 DELAY OF REGISTRATION; FURNISHING INFORMATION.

            (a) It shall be a  condition  precedent  to the  obligations  of the
Company to take any action  pursuant to Section 2.1, 2.2 or 2.3 that the selling
Holders shall furnish to the Company such information regarding themselves,  the
Registrable  Securities  held by them and the intended  method of disposition of
such  securities  as shall be  required  to  effect  the  registration  of their
Registrable Securities.

            (b)  The  Company  shall  have no  obligation  with  respect  to any
registration  requested  pursuant to Section 2.1 or Section 2.3 if the number of
shares of the Registrable Securities to be included in the registration does not
equal or  exceed  the  number of  shares  required  to  originally  trigger  the
Company's  obligation to initiate such  registration as specified in Section 2.1
or Section 2.3, whichever is applicable.

      2.8 INDEMNIFICATION.  In the event any Registrable Securities are included
in a registration statement under Sections 2.1, 2.2 or 2.3:

            (a) To the extent  permitted by law, the Company will  indemnify and
hold harmless each Holder, the partners,  officers and directors of each Holder,
any  underwriter  (as  defined in the  Securities  Act) for such Holder and each
person,  if any, who controls such Holder or  underwriter  within the meaning of
the Securities Act or the Exchange Act, against any losses, claims,  damages, or
liabilities  (joint or  several)  to which  they may  become  subject  under the
Securities Act, the Exchange Act or other federal or state law,  insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise out
of or are based upon any of the  following  statements,  omissions or violations
(collectively a "VIOLATION") by the Company: (i) any untrue statement or alleged
untrue  statement of a material fact contained in such  registration  statement,
including any preliminary  prospectus or final prospectus  contained  therein or
any amendments or supplements thereto,  (ii) the omission or alleged omission to
state  therein a material fact  required to be stated  therein,  or necessary to
make the statements  therein not  misleading,  or (iii) any violation or alleged
violation by the Company of the  Securities  Act,  the  Exchange  Act, any state
securities law or any rule or regulation  promulgated  under the Securities Act,
the Exchange Act or any state  securities  law in  connection  with the offering
covered by such registration statement;  and the Company will pay as incurred to
each such Holder, partner, officer, director,  underwriter or controlling person
for any legal or other expenses  reasonably  incurred by them in connection with
investigating or defending any such loss,  claim,  damage,  liability or action;
provided, however, that the indemnity agreement contained in this Section 2.8(a)
shall not apply to amounts paid in settlement of any such loss,  claim,  damage,
liability or action if such  settlement  is effected  without the consent of the
Company, which consent shall not be unreasonably withheld, nor shall the Company
be liable in any such case for any such loss, claim, damage, liability or action
to the extent that it arises out of or is based upon a Violation which occurs in
reliance upon and in conformity with written information furnished expressly for
use in  connection  with such  registration  by such Holder,  partner,  officer,
director, underwriter or controlling person of such Holder.


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            (b) To the extent permitted by law, each Holder will, if Registrable
Securities  held by such Holder are included in the  securities as to which such
registration qualifications or compliance is being effected,  indemnify and hold
harmless the Company,  each of its directors,  its officers and each person,  if
any,  who  controls the Company  within the meaning of the  Securities  Act, any
underwriter  and any other Holder  selling  securities  under such  registration
statement or any of such other Holder's  partners,  directors or officers or any
person  who  controls  such  Holder,  against  any  losses,  claims,  damages or
liabilities  (joint or  several)  to which  the  Company  or any such  director,
officer,  controlling  person,  underwriter  or other such  Holder,  or partner,
director,  officer or controlling person of such other Holder may become subject
under the  Securities  Act,  the  Exchange  Act or other  federal  or state law,
insofar as such losses,  claims,  damages or liabilities  (or actions in respect
thereto)  arise  out of or are  based  upon any  Violation,  in each case to the
extent (and only to the extent) that such Violation  occurs in reliance upon and
in conformity with written information  furnished by such Holder under a writing
provided to the  Company by such  Holder and stated to be for use in  connection
with such  registration;  and each such Holder will pay as incurred any legal or
other expenses reasonably incurred by the Company or any such director, officer,
controlling person,  underwriter or other Holder, or partner,  officer, director
or controlling  person of such other Holder in connection with  investigating or
defending any such loss, claim, damage,  liability or action if it is judicially
determined  that  there  was  such a  Violation;  provided,  however,  that  the
indemnity  agreement contained in this Section 2.8(b) shall not apply to amounts
paid in settlement of any such loss, claim, damage,  liability or action if such
settlement  is effected  without the consent of the Holder,  which consent shall
not be  unreasonably  withheld;  provided,  further,  that in no event shall any
indemnity under this Section 2.8 exceed the proceeds from the offering  received
by such Holder.

            (c)  Promptly  after  receipt  by an  indemnified  party  under this
Section  2.8  of  notice  of  the  commencement  of any  action  (including  any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying  party under this Section 2.8, deliver to
the  indemnifying  party a written  notice of the  commencement  thereof and the
indemnifying  party shall have the right to  participate  in, and, to the extent
the indemnifying  party so desires,  jointly with any other  indemnifying  party
similarly  noticed,   to  assume  the  defense  thereof  with  counsel  mutually
satisfactory to the parties; provided,  however, that an indemnified party shall
have the right to retain its own counsel,  with the fees and expenses to be paid
by the indemnifying  party, if  representation  of such indemnified party by the
counsel retained by the indemnifying  party would be inappropriate due to actual
or potential  differing  interests  between such indemnified party and any other
party  represented  by such counsel in such  proceeding.  The failure to deliver
written  notice  to the  indemnifying  party  within  a  reasonable  time of the
commencement  of any such action,  if materially  prejudicial  to its ability to
defend such action,  shall relieve such  indemnifying  party of any liability to
the  indemnified  party under this  Section  2.8, but the omission so to deliver
written  notice to the  indemnifying  party will not relieve it of any liability
that it may have to any indemnified party otherwise than under this Section 2.8.


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            (d) If the indemnification  provided for in this Section 2.8 is held
by a court of competent  jurisdiction to be unavailable to an indemnified  party
with respect to any losses,  claims,  damages or liabilities referred to herein,
the  indemnifying   party,  in  lieu  of  indemnifying  such  indemnified  party
thereunder,  shall to the extent  permitted by applicable  law contribute to the
amount  paid or  payable  by such  indemnified  party as a result of such  loss,
claim,  damage or liability in such  proportion as is appropriate to reflect the
relative fault of the indemnifying  party on the one hand and of the indemnified
party on the other in  connection  with the  Violation(s)  that resulted in such
loss,  claim,  damage  or  liability,  as well as any other  relevant  equitable
considerations.  The  relative  fault  of  the  indemnifying  party  and  of the
indemnified  party shall be  determined by a court of law by reference to, among
other things,  whether the untrue or alleged untrue statement of a material fact
or the omission to state a material fact relates to information  supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge,  access to  information  and  opportunity  to correct or prevent such
statement or omission;  provided,  that in no event shall any  contribution by a
Holder hereunder exceed the proceeds from the offering received by such Holder.

            (e) The  obligations  of the Company and Holders  under this Section
2.8 shall  survive  completion  of any offering of  Registrable  Securities in a
registration  statement and the termination of this  agreement.  No Indemnifying
Party,  in the defense of any such claim or litigation,  shall,  except with the
consent of each  Indemnified  Party,  consent to entry of any  judgment or enter
into any settlement which does not include as an unconditional  term thereof the
giving by the claimant or plaintiff to such Indemnified  Party of a release from
all liability in respect to such claim or litigation.

      2.9 ASSIGNMENT OF REGISTRATION  RIGHTS. The rights to cause the Company to
register Registrable  Securities pursuant to this Section 2 may be assigned by a
Holder to a  transferee  or assignee of  Registrable  Securities  which (a) is a
subsidiary, parent, general partner, limited partner, retired partner, member or
retired  member of a Holder,  (b) is a Holder's  family  member or trust for the
benefit of an individual  Holder, or (c) acquires at least ten thousand (10,000)
shares  of   Registrable   Securities   (as   adjusted   for  stock  splits  and
combinations); provided, however, (i) the transferor shall, within ten (10) days
after such  transfer,  furnish  to the  Company  written  notice of the name and
address of such  transferee or assignee and the securities with respect to which
such registration rights are being assigned and (ii) such transferee shall agree
to be subject to all restrictions set forth in this Agreement.


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      2.10 AMENDMENT OF REGISTRATION RIGHTS. Any provision of this Section 2 may
be amended and the observance  thereof may be waived  (either  generally or in a
particular  instance and either  retroactively or prospectively),  only with the
written  consent of the  Company  and the  Holders of at least a majority of the
Registrable Securities. Any amendment or waiver effected in accordance with this
Section 2.10 shall be binding upon each Holder and the Company. By acceptance of
any  benefits  under this Section 2, Holders of  Registrable  Securities  hereby
agree to be bound by the provisions hereunder.

      2.11 LIMITATION ON SUBSEQUENT  REGISTRATION RIGHTS. After the date of this
Agreement,  the  Company  shall not,  without the prior  written  consent of the
Holders of a majority of the Registrable Securities then outstanding, enter into
any agreement  with any holder or  prospective  holder of any  securities of the
Company that would grant such holder registration rights senior to those granted
to the Holders hereunder.

      2.12 RULE 144  REPORTING.  With a view to making  available to the Holders
the benefits of certain  rules and  regulations  of the SEC which may permit the
sale of the  Registrable  Securities  to the public  without  registration,  the
Company agrees to use its best efforts to:

            (a) Make and keep public information  available,  as those terms are
understood  and  defined  in SEC  Rule  144 or any  similar  or  analogous  rule
promulgated under the Securities Act, at all times;

            (b) File with the SEC,  in a timely  manner,  all  reports and other
documents required of the Company under the Exchange Act; and

            (c) So long as a Holder owns any Registrable Securities,  furnish to
such Holder forthwith upon request: a written statement by the Company as to its
compliance  with the reporting  requirements  of said Rule 144 of the Securities
Act,  and of the  Exchange  Act; a copy of the most recent  annual or  quarterly
report of the  Company;  and such other  reports and  documents  as a Holder may
reasonably  request  in  availing  itself of any rule or  regulation  of the SEC
allowing it to sell any such securities without registration.

III. MISCELLANEOUS

      3.1 GOVERNING LAW. This Agreement shall be governed by and construed under
the laws of the State of California as applied to  agreements  among  California
residents entered into and to be performed entirely within California.

      3.2 SURVIVAL. The representations,  warranties,  covenants, and agreements
made herein shall survive any  investigation  made by any Holder and the closing
of the transactions  contemplated  hereby.  All statements as to factual matters
contained in any  certificate or other  instrument  delivered by or on behalf of
the Company  pursuant  hereto in connection with the  transactions  contemplated
hereby  shall be deemed to be  representations  and  warranties  by the  Company
hereunder solely as of the date of such certificate or instrument.


                                       9
<PAGE>

      3.3 SUCCESSORS AND ASSIGNS. Except as otherwise expressly provided herein,
the  provisions  hereof shall inure to the benefit of, and be binding upon,  the
successors,  assigns, heirs, executors, and administrators of the parties hereto
and shall inure to the benefit of and be enforceable by each person who shall be
a holder of Registrable  Securities from time to time; provided,  however,  that
prior to the receipt by the Company of adequate  written  notice of the transfer
of any  Registrable  Securities  specifying  the full  name and  address  of the
transferee,  the Company  may deem and treat the person  listed as the holder of
such shares in its records as the  absolute  owner and holder of such shares for
all purposes, including the payment of dividends or any redemption price.

      3.4 ENTIRE AGREEMENT.  This Agreement and the Exhibit and Schedule hereto,
the Letter Agreement,  the Stock Purchase  Agreement and the Warrant  Agreements
and the other  documents  delivered  pursuant  thereto  constitute  the full and
entire  understanding  and  agreement  between  the  parties  with regard to the
subjects hereof and no party shall be liable or bound to any other in any manner
by  any  representations,   warranties,   covenants  and  agreements  except  as
specifically set forth herein and therein.

      3.5  SEVERABILITY.  In the  event  one or more of the  provisions  of this
Agreement  should,   for  any  reason,  be  held  to  be  invalid,   illegal  or
unenforceable in any respect, such invalidity,  illegality,  or unenforceability
shall not affect any other  provisions  of this  Agreement,  and this  Agreement
shall be construed as if such invalid,  illegal or  unenforceable  provision had
never been contained herein.

      3.6 AMENDMENT AND WAIVER.

            (a) Except as otherwise  expressly  provided herein,  this Agreement
may be amended or modified only upon the written  consent of the Company and the
holders of at least a majority of the Registrable Securities.

            (b) Except as otherwise  expressly  provided herein, the obligations
of the Company and the rights of the Holders under this  Agreement may be waived
only with the  written  consent of the  holders  of at least a  majority  of the
Registrable Securities.

      3.7  DELAYS  OR  OMISSIONS.  It is  agreed  that no delay or  omission  to
exercise any right,  power, or remedy  accruing to any Holder,  upon any breach,
default or  noncompliance  of the Company under this Agreement  shall impair any
such right,  power,  or remedy,  nor shall it be construed to be a waiver of any
such breach,  default or noncompliance,  or any acquiescence  therein, or of any
similar breach,  default or noncompliance  thereafter  occurring.  It is further
agreed that any waiver, permit, consent, or approval of any kind or character on
any Holder's part of any breach, default or noncompliance under the Agreement or
any  waiver  on such  Holder's  part of any  provisions  or  conditions  of this
Agreement  must  be in  writing  and  shall  be  effective  only  to the  extent
specifically  set  forth  in such  writing.  All  remedies,  either  under  this
Agreement, by law, or otherwise afforded to Holders, shall be cumulative and not
alternative.


                                       10
<PAGE>

      3.8  NOTICES.  All notices  required or  permitted  hereunder  shall be in
writing and shall be deemed effectively given: (a) upon personal delivery to the
party to be notified,  (b) when sent by facsimile if sent during normal business
hours of the recipient; if not, then on the next business day, (c) five (5) days
after  having  been  sent  by  registered  or  certified  mail,  return  receipt
requested,  postage prepaid,  or (d) one (1) day after deposit with a nationally
recognized  overnight  courier,  specifying  next  day  delivery,  with  written
verification  of receipt.  All  communications  shall be sent to the party to be
notified at the address as set forth on the signature pages hereof or Schedule 1
hereto or at such other  address as such  party may  designate  by ten (10) days
advance written notice to the other parties hereto.

      3.9 ATTORNEYS' FEES. In the event that any suit or action is instituted to
enforce any provision in this  Agreement,  the prevailing  party in such dispute
shall be entitled to recover from the losing party all fees,  costs and expenses
of enforcing  any right of such  prevailing  party under or with respect to this
Agreement,  including without  limitation,  such reasonable fees and expenses of
attorneys and accountants,  which shall include,  without limitation,  all fees,
costs and expenses of appeals.

      3.10 TITLES AND SUBTITLES.  The titles of the sections and  subsections of
this  Agreement  are  for  convenience  of  reference  only  and  are  not to be
considered in construing this Agreement.

      3.11  COUNTERPARTS.  This  Agreement  may be  executed  in any  number  of
counterparts,  each of which  shall be an  original,  but all of which  together
shall  constitute  one  instrument.  This Agreement may be executed by facsimile
signature.


                                       11
<PAGE>

IV. LIMITATION ON EARTHSHELL CORPORATION DIRECT LIABILITY

      Notwithstanding  any  provision  to the contrary in this  Investor  Rights
Agreement,  the letter  agreement,  dated December 9, 2005,  between  EarthShell
Corporation and EarthShell Asia, Limited, pursuant to which this Investor Rights
Agreement  has been  issued,  or the  agreements  and  letters  to be  delivered
pursuant  to the  terms of such  letter  agreement,  if  EarthShell  Corporation
defaults  under  the  terms  of  this  Investor  Rights  Agreement,  the  letter
agreement, dated December 9, 2005, between EarthShell Corporation and EarthShell
Asia, Limited, pursuant to which this Investor Rights Agreement has been issued,
and/or the agreements and letters to be delivered  pursuant to the terms of such
letter  agreement,  EarthShell  Asia,  Limited,  each of the  signatories to the
agreements  delivered  pursuant to the letter agreement,  including the Investor
under this Investor  Rights  Agreement,  each of the holders of EA Shares and EA
Warrants,  as defined in such letter  agreement,  individually and collectively,
shall under no  circumstances  be entitled to recover or collect  directly  from
EarthShell  Corporation,  whether by Fee Damages, as such term is defined in the
letter agreement,  or judgment for damages or otherwise, an aggregate amount for
any and all  EarthShell  Corporation  defaults  which  exceeds  the total of (i)
$900,000,  plus (ii) the total of all Technology  Fees paid by EarthShell  Asia,
Limited  to  EarthShell  Corporation  under the  terms of the  Asian  Sublicense
Agreements,  as such term is  defined in the  letter  agreement,  plus (iii) the
total of all royalties paid by EarthShell Asia,  Limited to EarthShell under the
terms of the Five Sublicenses,  as such term is defined in the letter agreement,
prior to the date of such  collection  or  recovery.  To the  extent one or more
judgments is not satisfied in full directly from EarthShell  Corporation because
of the foregoing limitation on EarthShell  Corporation's  direct liability,  the
balance or balances  may be withheld by  EarthShell  Asia,  Limited  from future
Technology Fee or royalty payments  otherwise due from EarthShell Asia,  Limited
to EarthShell Corporation under the terms of the Five Sublicenses,  as such term
is defined in the letter agreement,  and applied by EarthShell Asia,  Limited to
such balance or balances, whether the balance or balances are owed to EarthShell
Asia,  Limited,  a signatory  to an agreement  delivered  pursuant to the letter
agreement or to a holder of EA Shares or EA Warrants,  as such terms are defined
in the letter agreement.

                            [signature page follows]


                                       12
<PAGE>

      IN WITNESS WHEREOF,  the parties hereto have executed this INVESTOR RIGHTS
AGREEMENT as of the date set forth in the first paragraph hereof


                                       COMPANY: EarthShell Corporation

                                       By: /s/ Scott Houston
                                           -------------------------------------
                                           Name:    Scott Houston
                                           Title:   Chief Financial Officer


                                       INVESTORS:



                                       /s/ Steven L. Galvanoni, Trustee
                                       -----------------------------------------
                                       Steven L. Galvanoni, as trustee of the
                                       Steven L. Galvanoni Trust



                                       /s/ Greg C. Hoffman
                                       -----------------------------------------
                                       Greg C. Hoffman



                                       /s/ Monty Waltz
                                       -----------------------------------------
                                       Monty Waltz



                                       /s/ Ying Wang
                                       -----------------------------------------
                                       Ying Wang



                 [Signature Page to Investors Rights Agreement]

<PAGE>

                                   SCHEDULE 1

                              SCHEDULE OF INVESTORS
                              ---------------------


166,667 PREVIOUSLY PURCHASED EA SHARES
--------------------------------------

NAME                                                        NUMBER OF SHARES
----------------------------------------------------------- --------------------
Ying Wang                                                   83,333
----------------------------------------------------------- --------------------
Monty Waltz                                                 33,333
----------------------------------------------------------- --------------------
Steven L. Galvanoni,                                        33,333
as trustee of the Steven L. Galvanoni Trust
----------------------------------------------------------- --------------------
Greg Hoffman                                                16,668
----------------------------------------------------------- --------------------
         TOTAL                                              166,667
----------------------------------------------------------- --------------------

100,000 ADDITIONAL EA SHARES
----------------------------

NAME                                                        NUMBER OF SHARES
----------------------------------------------------------- --------------------
Steven L. Galvanoni,                                        50,000
as trustee of the Steven L. Galvanoni Trust
----------------------------------------------------------- --------------------
Greg Hoffman                                                50,000
----------------------------------------------------------- --------------------
         TOTAL                                              100,000
----------------------------------------------------------- --------------------

