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                                                                   EXHIBIT 10.31

                        SEPARATION AND RELEASE AGREEMENT

     This SEPARATION AND RELEASE AGREEMENT (this "Agreement") is made and
entered into by and between PLANETCAD Inc., a Delaware corporation
("PlanetCAD"), and Jim Bracking ("Mr. Bracking") (collectively "parties") and
shall be effective on the date on which Mr. Bracking executes it (the "Effective
Date").

                                   I. RECITALS

     WHEREAS, effective as of January 25, 2002, immediately following
approximately two weeks of paid vacation, Mr. Bracking's employment as Chief
Executive Officer and President and any and all other employment positions that
Mr. Bracking may have held at PlanetCAD or its subsidiaries, including
directorships, shall cease; and

     WHEREAS, the parties wish to make the separation amicable but conclusive on
the terms and conditions set forth herein; and

     WHEREAS, the mutual considerations expressed herein are deemed by each
party sufficient for their respective promises and covenants; and

     WHEREAS, Mr. Bracking accepts the benefits of this Agreement with the
acknowledgment that by its terms he has been fully and satisfactorily
compensated.

                                  II. COVENANTS

     THEREFORE, in consideration of the mutual promises and covenants contained
in this Agreement, it is hereby agreed by and between the parties hereto as
follows:

     1.  TERMINATION OF EMPLOYMENT AND SEVERANCE PAYMENTS. As of January 25,
2002 (the "Separation Date"), Mr. Bracking's employment as Chief Executive
Officer, President and any and all other employment positions that Mr. Bracking
may have held at PlanetCAD or its subsidiaries shall cease. In furtherance of
the preceding sentence, Mr. Bracking hereby resigns, effective as of the
Separation Date, as a director on the Board of Directors of PlanetCAD. No later
than January 29, 2002, PlanetCAD shall pay Mr. Bracking the gross amount of
$12,980.40, less legally required withholdings, which the parties agree
represents the value of Bracking's accrued, unused vacation pay as of the
Separation Date. From the Separation Date until May 9, 2002 (the "Severance
Period"), PlanetCAD shall pay Mr. Bracking a total gross amount of $65,625,
$32,812.50 of which shall be paid, less legally required withholdings, in a lump
sum on January 29, 2002, and the remaining $32,812.50 of which shall be paid,
less legally required withholdings, in seven semimonthly installments in
accordance with PlanetCAD's standard payment practices during the Severance
Period. PlanetCAD will reimburse Mr. Bracking for the expenses that he incurs in
continuing, through July 31, 2002, his benefits, as permitted by COBRA.
Thereafter, Mr. Bracking may continue such coverage pursuant to COBRA, at his
own expense. PlanetCAD will extend, for one year from the

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Separation Date, the expiration date of Mr. Bracking's vested stock options from
April 25, 2002 (the 90th day following the Separation Date as provided in Mr.
Bracking's incentive stock option agreement dated December 14, 2000) to January
25, 2003. Mr. Bracking acknowledges that (i) any vested stock option retained by
Mr. Bracking after the 90th day following the Separation Date will be deemed to
be a nonstatutory stock option, and (ii) he has had the opportunity to consult
with tax counsel of his choice regarding the effect thereof. Mr. Bracking shall
be entitled to retain the laptop computer (excluding all peripheral hardware
such as independent monitors and keyboards) and cellular telephone that he used
during the term of his employment with PlanetCAD, but all cellular telephone
service fees, internet access fees and other related service fees and charges
incurred in connection with the use of either the laptop computer or the
cellular telephone after the Separation Date will be Mr. Bracking's sole
responsibility. PlanetCAD shall withhold federal income taxes from the payments
made under this paragraph at a rate not exceeding the 28% supplemental income
rate.

     2.  ACKNOWLEDGEMENTS. Except as provided for in paragraph 1, Mr. Bracking
acknowledges and agrees that before the Effective Date of this Agreement he had
been paid all sums that he had earned, or to which he otherwise was entitled, in
connection with his employment with PlanetCAD. Furthermore, with respect to Mr.
Bracking's rights under the Older Worker's Benefits Protection Act:

     (a) Mr. Bracking agrees and acknowledges that he: (i) understands the
language used in this Agreement and the Agreement's legal effect; (ii)
understands that by signing this agreement he is giving up the right to sue
PlanetCAD for age discrimination; (iii) will receive compensation under this
Agreement to which he would not have been entitled without signing this
Agreement; (iv) has been advised by PlanetCAD to consult with an attorney before
signing this Agreement; and (v) was given no less than twenty-one days to
consider whether to sign this agreement.

     (b) For a period of seven days after the Effective Date, Mr. Bracking may,
in his sole discretion, rescind this Agreement by delivering a written notice of
rescission to PlanetCAD. If Mr. Bracking rescinds this Agreement within seven
calendar days after the Effective Date, this Agreement shall be void, all
actions taken pursuant to this Agreement shall be reversed, and neither this
Agreement nor the fact of or circumstances surrounding its execution shall be
admissible for any purpose whatsoever in any proceeding between the parties,
except in connection with a claim or defense involving the validity or effective
rescission of this Agreement. If Mr. Bracking does not rescind this Agreement
within seven calendar days after the Effective Date, this Agreement shall become
final and binding and shall be irrevocable.

     3.  OTHER COMPENSATION. Except as expressly provided herein, Mr. Bracking
acknowledges and agrees that he will not receive (nor is he entitled to receive)
any additional consideration, payments, reimbursements, incentive payments,
stock, equity interests, or benefits of any kind. Mr. Bracking also acknowledges
and agrees that neither this Agreement, nor any other agreement that he has with
PlanetCAD, creates any obligation on the part of PlanetCAD to repurchase any
shares of PlanetCAD stock owned by Mr. Bracking at any time. Mr. Bracking
further acknowledges and agrees that his unvested stock options have been
cancelled.

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     4.  DENIAL OF LIABILITY. The parties acknowledge that any payment by
PlanetCAD and any release by Mr. Bracking pursuant to this Agreement are made in
compromise of disputed claims; that in making any such payment or release,
PlanetCAD and Mr. Bracking in no way admit any liability to each other; and that
the parties expressly deny any such liability.

     5.  NONDISPARAGEMENT. Mr. Bracking and PlanetCAD agree that neither party
will at any time disparage the other to third parties in any manner likely to be
harmful to the other party, their business reputation, or the personal or
business reputation of its directors, shareholders and/or employees.
Notwithstanding the prohibition in the preceding sentence, each party shall
respond accurately and fully to any question, inquiry, or request for
information when required by legal process.

     6.  PLANETCAD PROPERTY. Immediately preceding the Separation Date, Mr.
Bracking agrees to return to PlanetCAD all PlanetCAD documents (and all copies
thereof) and any and all other PlanetCAD property in his possession, custody or
control, including, but not limited to, financial information, customer
information, customer lists, employee lists, PlanetCAD files, notes, cellular
telephones, contracts, drawings, records, business plans and forecasts,
financial information, specifications, computer-recorded information, software,
tangible property, credit cards, entry cards, identification badges and keys,
and any materials of any kind which contain or embody any proprietary or
confidential material of PlanetCAD and all reproductions thereof (collectively,
"PlanetCAD Information"). Notwithstanding any other provision of this Agreement,
this Agreement shall not prohibit Mr. Bracking from making and retaining a paper
and/or electronic copy of his personal contact database.

     7.  NONSOLICITATION, NONDISCLOSURE OF PROPRIETARY INFORMATION,
NONCOMPETITION. Mr. Bracking acknowledges and agrees that he has executed and is
and shall be bound by the Proprietary Information Agreement attached as Exhibit
A, which is and shall remain a separate and distinct agreement between Mr.
Bracking and PlanetCAD and which shall survive the execution of this Agreement.
Nothing in this Agreement shall be construed to narrow, supercede, modify or
affect in any way the obligations of Mr. Bracking imposed by that or any other
agreement, law, or other source.

     8.  CONFIDENTIALITY OF AGREEMENT. Mr. Bracking and PlanetCAD acknowledge
that confidentiality and nondisclosure are material considerations for the
parties entering into this Agreement. As such, the provisions of this Agreement
shall be held in strictest confidence by Mr. Bracking and PlanetCAD and shall
not be publicized or disclosed in any manner whatsoever, including but not
limited to, the print or broadcast media, any public network such as the
Internet, any other outbound data program such as computer generated mail,
reports or faxes, or any source likely to result in publication or computerized
access. Notwithstanding the prohibition in the preceding sentence: (a) the
parties may disclose this Agreement in confidence to their respective attorneys,
accountants, auditors, tax preparers, and financial advisors; (b) PlanetCAD may
disclose this Agreement as necessary to fulfill standard or legally required
corporate reporting or disclosure requirements; (c) the parties may disclose
this Agreement upon request from any government entity or court of law; (d) the
parties may disclose this Agreement insofar as such disclosure may be necessary
to enforce its terms or as otherwise required by law, including without
limitation as required by any form of securities-related statute or regulation;

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and (e) Bracking may disclose this Agreement to members of his immediate family,
provided that if any such person discloses any term of this Agreement to any
person other than a member of Bracking's immediate family, then Bracking shall
be deemed to have breached this confidentiality covenant and PlanetCAD shall be
entitled to all remedies to which it would have been entitled had Bracking
himself made such disclosure. Notwithstanding any other provision of this
Agreement, if PlanetCAD discloses this Agreement pursuant to any
securities-related disclosure obligation, or otherwise intentionally makes this
Agreement public, PlanetCAD and Bracking shall be released of any further
obligations under this paragraph 8.

     9.  COVENANT NOT TO COMPETE. During the six months following the Separation
Date, Mr. Bracking shall not, directly or indirectly, as an officer, director,
employee, consultant, owner, shareholder, adviser, joint venturer, or otherwise,
compete with PlanetCAD anywhere in the world (the "Protected Region") in: (i)
the development, implementation, marketing or sale of automated solutions for
manufacturing and design engineers to enable engineering data interchange,
improve data quality for CAD drawings and streamline the manufacturing process;
or (ii) any other line of business in which PlanetCAD was engaged at the
Effective Date; or (iii) any other line of business into which PlanetCAD, during
Mr. Bracking's employment with PlanetCAD, formed an intention to enter during
the Severance Period. This covenant shall not prohibit Mr. Bracking from owning
less than two percent of the securities of any competitor of PlanetCAD, if such
securities are publicly traded on a nationally recognized stock exchange or
over-the-counter market. Mr. Bracking acknowledges that the foregoing geographic
restriction on competition is fair and reasonable, given the nature and
geographic scope of PlanetCAD's business operations and the nature of Mr.
Bracking's position with PlanetCAD. Mr. Bracking also acknowledges that while
employed by PlanetCAD, Mr. Bracking has had access to information that would be
valuable or useful to PlanetCAD's competitors, and therefore acknowledges that
the foregoing restrictions on Mr. Bracking's future activities are fair and
reasonable.

     Mr. Bracking acknowledges the following provisions of Colorado law, set
forth in Colorado Revised Statutes Section 8-2-113(2):

          Any covenant not to compete which restricts the right of any person to
receive compensation for performance of skilled or unskilled labor for any
employer shall be void, but this subsection (2) shall not apply to:
          ...
          (b) Any contract for the protection of trade secrets;
          ...
          (d) Executive and management personnel and officers and employees who
constitute professional staff to executive and management personnel.

     Mr. Bracking acknowledges that this Agreement is a contract for the
protection of trade secrets within the meaning of Section 8-2-113(2)(b) and is
intended to protect the confidential PlanetCAD Information and confidential
records identified above and that during his

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employment with PlanetCAD he served as an executive or manager, or professional
staff to an executive or manager, within the meaning of Section 8-2-113(2)(d).

     10. RELEASE OF CLAIMS BY MR. BRACKING. For the consideration set forth in
this Agreement and the mutual covenants of PlanetCAD and Mr. Bracking, Mr.
Bracking hereby releases, acquits and forever discharges PlanetCAD and its
affiliated corporations and entities, predecessors, officers, directors, agents,
representatives, servants, attorneys, employees, shareholders, heirs, personal
representative, spouses, beneficiaries, executors, trustees, successors and
assigns of and from any and all claims, liabilities, demands, causes of action,
costs, expenses, attorneys' fees, damages, indemnities and obligations of every
kind and nature, in law, equity, or otherwise, known or unknown, suspected and
unsuspected, disclosed and undisclosed, liquidated or contingent, arising out of
or in any way related to agreements, events, acts or conduct at any time prior
to and including the Effective Date, including but not limited to: any and all
such claims and demands directly or indirectly arising out of or in any way
connected with Mr. Bracking's employment with PlanetCAD or the conclusion of
that employment; claims or demands related to salary, bonuses, commissions,
incentive payments, stock, stock options, or any ownership or equity interests
in PlanetCAD; vacation pay, personal time off, fringe benefits, expense
reimbursements, sabbatical benefits, severance benefits, or any other form of
compensation, including any severance or other benefits and all other rights
under the Change of Control Agreement dated on or about November 19, 2001
between PlanetCAD and Mr. Bracking; claims pursuant to any federal, any state or
any local law, statute, common law or cause of action including, but not limited
to, the federal Civil Rights Act of 1964, as amended; attorney's fees, costs, or
any other expenses under Title VII of the Civil Rights Act of 1964, as amended;
the Employment Retirement Income Security Act; the federal Americans with
Disabilities Act of 1990; the Family and Medical Leave Act; the Colorado
Discrimination and Unfair Employment Act, tort law; wrongful discharge;
discrimination; harassment; fraud; negligence, breach of fiduciary duty; claims
for expense reimbursement; defamation; libel; emotional distress; and breach of
the implied covenant of good faith and fair dealing. Mr. Bracking warrants and
represents that he has not filed or otherwise made or asserted any claim,
complaint, or charge against PlanetCAD or any predecessor, affiliate or agent
thereof with any entity including without limitation the Equal Employment
Opportunity Commission and any local, state or federal administrative body or
court. Mr. Bracking agrees that in the event he brings a claim or charge covered
by this release or does not dismiss and withdraw any claim covered by this
release, in which he seeks damages or any other relief against PlanetCAD or in
the event he seeks to recover against PlanetCAD in any claim brought by a
governmental agency on his behalf, this Agreement shall serve as a complete
defense to such claims or charges. By this provision, Mr. Bracking does not
waive any right he has to assert claims in the future based upon any act or
omission committed by PlanetCAD after the Effective Date of this Agreement. In
addition, nothing in this release shall impair Mr. Bracking's rights to be
defended or indemnified by PlanetCAD or its insurance carriers for any claim
made against him arising out of or relating to his work for PlanetCAD.

     11. PLANETCAD RELEASE OF MR. BRACKING. PlanetCAD, for itself and its
affiliates (collectively, "PlanetCAD Releasers"), hereby fully and forever
releases and discharges Mr. Bracking, his heirs, representatives, assigns,
attorneys, and any and all other persons or

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entities that are now or may become liable to any PlanetCAD Releaser on account
of Mr. Bracking's employment with PlanetCAD or separation therefrom, all of whom
are collectively referred to as "PlanetCAD Releases," of and from any and all
actions, causes of action, claims, demands, costs and expenses, including
attorneys' fees, of every kind and nature whatsoever, in law or in equity,
whether now known or unknown, that PlanetCAD Releasers, or any person acting
under any of them, may now have, or claim at any future time to have, based in
whole or in part upon any act or omission occurring before the Effective Date,
without regard to present actual knowledge of such acts or omissions; EXCEPT as
specifically provided otherwise in this Agreement; and EXCEPT claims arising
from or relating to any intentional or willful act or omission on the part of
Mr. Bracking.

     12. TAX CONSEQUENCES. Mr. Bracking agrees to pay the employee share of all
taxes due in connection with payment or other benefits he receives under this
Agreement, and to indemnify PlanetCAD for and hold PlanetCAD harmless from any
and all of the employee share of all taxes, interest, penalties and all related
costs and expenses asserted against or incurred by PlanetCAD in connection with
any failure to withhold or pay taxes due on any consideration provided by
PlanetCAD pursuant to this Agreement. Mr. Bracking expressly acknowledges that
PlanetCAD has not made, nor herein makes, any representation about the tax
consequences of any consideration provided by PlanetCAD to Mr. Bracking pursuant
to this Agreement, and that he understands that he should seek professional tax
advice before executing this Agreement.

     13. ADMINISTRATIVE MATTERS. Mr. Bracking covenants that following the
Effective Date he will not take any action, or encourage any other person to
take any action, calculated or likely to result in the initiation or an inquiry,
investigation or other action concerning PlanetCAD by any federal, state or
local governmental body or agency, and that were he to do so he would commit a
material breach and default under this Agreement, for which PlanetCAD would be
entitled to return of all sums paid to Mr. Bracking under this Agreement and, in
addition, all remedies available to PlanetCAD pursuant to applicable law,
including specific performance of this covenant. Notwithstanding any other
provision of this Agreement, this Agreement shall not preclude Mr. Bracking from
testifying truthfully in response to any subpoena or other compulsory legal
process served upon him by any person, entity or governmental authority.

     14. COVENANT OF COOPERATION IN LITIGATION. Mr. Bracking acknowledges that
because of his position with PlanetCAD, he may possess information that may be
relevant to or discoverable in litigation in which PlanetCAD is involved or may
in the future be involved. Mr. Bracking agrees that he shall testify truthfully
in connection with any such litigation, shall cooperate with PlanetCAD in
connection with such litigation, and that his duty of cooperation shall include
an obligation to meet with PlanetCAD representatives and/or counsel, at mutually
agreeable times and places (provided that both parties shall exercise their best
efforts to cooperate in connection with the scheduling of such meetings),
concerning such litigation for such purposes as PlanetCAD deems necessary, in
its sole discretion, and to appear for deposition upon PlanetCAD's request and
without a subpoena. Mr. Bracking shall not be entitled to any compensation in
connection with his duty of cooperation, except that PlanetCAD shall reimburse
Mr. Bracking for reasonable out-of-pocket expenses and any lost income that he
incurs in

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honoring his obligation of cooperation, upon Mr. Bracking's submission of
documentation of such costs and lost income in a form satisfactory to PlanetCAD
in its reasonable discretion.

     15. NO THIRD-PARTY RIGHTS. The parties agree that by making this Agreement
they do not intend to confer any benefits, privileges, or rights to others. The
Agreement is strictly between the parties hereto, subject to the terms of
paragraph 19 below, and that it shall not be construed to vest in any other the
status of third-party beneficiary.

     16. VOLUNTARY AND KNOWINGLY. Mr. Bracking acknowledges that in executing
this Agreement, he has reviewed it and understands its terms and has had an
opportunity and was advised to seek guidance from counsel of his own choosing,
and was fully advised of his rights under law, and acted knowingly and
voluntarily.

     17. DUTY TO EFFECTUATE. The parties agree to perform any lawful additional
acts, including the execution of additional agreements, as are reasonably
necessary to effectuate the purpose of this Agreement.

     18. ENTIRE AGREEMENT. This Agreement, including the incorporated Exhibit A,
constitutes the complete, final and exclusive embodiment of the entire agreement
between Mr. Bracking and PlanetCAD with regard to the subject matter hereof.
This Agreement is entered into without reliance on any promise or
representation, written or oral, other than those expressly contained herein. It
may not be modified except in writing signed by Mr. Bracking and any successor
President and CEO of PlanetCAD Inc.

     19. SUCCESSORS AND ASSIGNS. This Agreement shall bind the heirs, personal
representatives, successors, assigns, executors and administrators of each
party, and inure to the benefit of each party, its heirs, successors and
assigns.

     20. APPLICABLE LAW. The parties agree and intend that this Agreement be
construed and enforced in accordance with the laws of the State of Colorado.

     21. FORUM. Any controversy arising out of or relating to this Agreement or
the breach thereof, or any claim or action to enforce this Agreement or portion
thereof, or any controversy or claim requiring interpretation of this Agreement
must be brought in a forum located within the State of Colorado. No such action
may be brought in any forum outside the State of Colorado. Any action brought in
contravention of this paragraph by one party is subject to dismissal at any time
and at any stage of the proceedings by the other, and no action taken by the
other in defending, counterclaiming, or appealing shall be construed as a waiver
of this right to immediate dismissal. A party bringing an action in
contravention of this paragraph shall be liable to the other party for the
costs, expenses and attorney's fees incurred in successfully dismissing the
action or successfully transferring the action to a forum located within the
State of Colorado.

     22. SEVERABLE. If any provision of this Agreement is determined to be
invalid, void or unenforceable, in whole or in part, this determination will not
affect any other provision of this Agreement, and the provision in question
shall be modified so as to be rendered enforceable.

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     23. ENFORCE ACCORDING TO TERMS. The parties intend this Agreement to be
enforced according to its terms.

     24. ATTORNEY'S FEES. The prevailing party in an action to enforce the terms
of this Agreement shall be entitled to its reasonable costs, expenses, and
attorney's fees.

     25. SECTION HEADINGS. The section and paragraph headings contained in this
Agreement are for reference purposes only and shall not affect in any way the
meaning or interpretation of this Agreement.

     IN WITNESS WHEREOF, the parties have duly authorized and caused this
Agreement to be executed as follows:

Jim Bracking                                PLANETCAD INC.
An individual

/s/ Jim Bracking                            By:      /s/ Joy Godesiabois
----------------------------------             ------------------------------
Jim Bracking
                                            Its:     CFO
                                                -----------------------------

Date:      January 24      , 2002           Date:        2/11         , 2002
     ----------------------                      ---------------------

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