Document:

Amended and Restated Investors' Rights Agreement

 Exhibit 10.5 
 AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT 
 THIS AMENDED AND
RESTATED INVESTORS’ RIGHTS AGREEMENT (this “Agreement”) is made as of the 19th day of July, 2011, by and among Proto Labs, Inc., a Minnesota corporation (the “Company”), and each of the investors listed on
Schedule A hereto, each of which is referred to in this Agreement as an “Investor,” and amends and restates that certain Investors’ Rights Agreement (the “Predecessor Agreement”), dated as of
August 1, 2008, by and among the Company, North Bridge Growth Equity I, L.P., a Delaware limited partnership (“North Bridge”) and Protomold Investment Company, LLC, a Minnesota limited liability company
(“PIC”). 
 RECITALS 
 A. The Company and PIC terminated that certain Stock Purchase Agreement, dated June 17, 2005, as amended (the “PIC Agreement”) and replaced it with the Predecessor Agreement.

 B. The Company and North Bridge are parties to the Series A Preferred Stock Purchase Agreement, dated as of August 1,
2008 (the “Purchase Agreement”). 
 C. In order to induce the Company to enter into the Purchase Agreement and
to induce North Bridge, an Investor under the Predecessor Agreement, to invest funds in the Company pursuant to the Purchase Agreement, North Bridge and the Company executed the Predecessor Agreement. 

D. The Company, North Bridge and PIC, together with the other Investors listed on Schedule A, desire to amend and restate the
Predecessor Agreement to reflect certain agreements reached by such parties, including the granting of piggyback registration rights as described below to each of the Lawrence Lukis, Bradley A. Cleveland, individually and as trustee of the Bradley
A. Cleveland Declaration of Trust dated October 10, 2008, Donald Krantz and Mark Kubicek, and Patricia M. Cleveland and Cornerstone Private Asset Trust Company, LLC, as Co-Trustees of the KEC 2011 Irrevocable Gift Trust and the JMC 2011
Irrevocable Gift Trust (collectively the “Management Investors” and each a “Management Investor”). 
 NOW, THEREFORE, the parties agree as follows: 
  

	 	1.	Definitions. For purposes of this Agreement: 

 1.1 “Affiliate” means, with respect to any specified Person, any other Person who, directly or indirectly, controls, is controlled by, or is under common control with such Person,
including without limitation any general partner, managing member, officer or director of such Person or any venture capital fund now or hereafter existing that is controlled by one or more general partners or managing members of, or shares the same
management company with, such Person. 
 1.2 “Common Stock” means shares of the Company’s common stock,
par value $.001 per share. 

  

					
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 1.3 “Damages” means any loss, damage, or liability (joint or several) to
which a party hereto may become subject under the Securities Act, the Exchange Act, or other federal or state law, insofar as such loss, damage, or liability (or any action in respect thereof) arises out of or is based upon (i) any untrue
statement or alleged untrue statement of a material fact contained in any registration statement of the Company, including any preliminary prospectus or final prospectus contained therein or any amendments or supplements thereto; (ii) an
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 indemnifying party (or any of its agents
or Affiliates) 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. 

1.4 “Derivative Securities” means any securities or rights convertible into, or exercisable or exchangeable for (in each
case, directly or indirectly), Common Stock, including options and warrants. 
 1.5 “Exchange Act” means the
Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder. 
 1.6
“Excluded Registration” means (i) a registration relating to the sale of securities to employees of the Company or a subsidiary pursuant to a stock option, stock purchase, or similar plan; (ii) a registration
relating to an SEC Rule 145 transaction; (iii) a registration on any form that does not include substantially the same information as would be required to be included in a registration statement covering the sale of the Registrable Securities;
or (iv) a registration in which the only Common Stock being registered is Common Stock issuable upon conversion of debt securities that are also being registered. 
 1.7 “Form S-1” 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. 
 1.8 “Form S-3” means such form under the Securities Act as in effect on the date hereof or any
registration form under the Securities Act subsequently adopted by the SEC that permits incorporation of substantial information by reference to other documents filed by the Company with the SEC. 

1.9 “GAAP” means generally accepted accounting principles in the United States. 

1.10 “Holder” means any holder of Registrable Securities who is a party to this Agreement. 

1.11 “Immediate Family Member” means a child, stepchild, grandchild, parent, stepparent, grandparent,
spouse, domestic partner, sibling, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law, including adoptive relationships, of a natural person referred to herein. 

  

					
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 1.12 “Initiating Holders” means, collectively, Holders who properly
initiate a registration request under this Agreement. 
 1.13 “IPO” means the Company’s first
firm-commitment underwritten public offering of its Common Stock pursuant to an effective registration statement under the Securities Act. 
 1.14 “Major Holder” means North Bridge or PIC, so long as each, respectively, remains a Holder. 
 1.15 “Major Investor” means any of North Bridge or PIC, individually or together with such Investor’s Affiliates, so long as such Investor holds at least 75,000 shares of Registrable
Securities (as adjusted for any stock split, stock dividend, combination, or other recapitalization or reclassification effected after the date hereof). 
 1.16 “New Securities” means, collectively, equity securities of the Company, whether or not currently authorized, as well as rights, options, or warrants to purchase such equity
securities, or securities of any type whatsoever that are, or may become, convertible or exchangeable into or exercisable for such equity securities. 
 1.17 “Person” means any individual, corporation, partnership, trust, limited liability company, association or other entity. 

1.18 “Qualified IPO” means the Company’s first firm-commitment underwritten public offering of its Common Stock
pursuant to an effective registration statement under the Securities Act (provided that if such a public offering is consummated before August 1, 2012, the offering price must be at least $244.12 per share (subject to appropriate adjustment in
the event of any stock dividend, stock split, combination or other similar recapitalization), resulting in at least $40,000,000 of aggregate gross proceeds to the Company). 
 1.19 “Registrable Securities” means (i) the Common Stock issuable or issued upon conversion of the Series A Preferred Stock, (ii) the Common Stock issued to PIC, (iii) the
Common Stock issued to any Management Investor, and (iv) any Common Stock issued as (or issuable upon the conversion or exercise of any warrant, right, or other security that is issued as) a dividend or other distribution with respect to, or in
exchange for or in replacement of, the shares referenced in clauses (i) and (iii) above; excluding in all cases, however, any Registrable Securities sold by a Person in a transaction in which the applicable rights under this Agreement are
not assigned pursuant to Section 5.1, and excluding for purposes of Section 2 any shares for which registration rights have terminated pursuant to Section 2.14 of this Agreement. 

1.20 “Registrable Securities then outstanding” means the number of shares determined by adding the number of shares of
outstanding Common Stock that are Registrable Securities and the number of shares of Common Stock issuable (directly or indirectly) pursuant to then exercisable and/or convertible securities that are Registrable Securities. 

1.21 “Restricted Securities” means the securities of the Company required to bear the legend set forth in
Section 2.12(b) hereof. 

  

					
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 1.22 “SEC” means the Securities and Exchange Commission. 

1.23 “SEC Rule 144” means Rule 144 promulgated by the SEC under the Securities Act. 

1.24 “SEC Rule 145” means Rule 145 promulgated by the SEC under the Securities Act. 

1.25 “Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated
thereunder. 
 1.26 “Selling Expenses” means all underwriting discounts, selling commissions, and stock
transfer taxes applicable to the sale of Registrable Securities, and fees and disbursements of counsel for any Holder, except for the fees and disbursements of the Selling Holder Counsel borne and paid by the Company as provided in
Section 2.6. 
 1.27 “Series A Director” means any director of the Company that the holders of
record of the Series A Preferred Stock are entitled to elect pursuant to the Company’s Amended and Restated Articles of Incorporation. 
 1.28 “Series A Holder” means North Bridge Growth Equity I, L.P. 

1.29 “Series A Preferred Stock” means shares of the Company’s Series A Preferred Stock, par value $.001 per share.

  

	 	2.	Registration Rights. The Company covenants and agrees as follows: 

 2.1 Demand Registration. 
 (a) Form S-1 Demand. If at any time
following 180 days after the effective date of the registration statement for an IPO, the Company receives a request from Major Holders of the Registrable Securities then outstanding that the Company file a Form S-1 registration statement with
respect to outstanding Registrable Securities having an anticipated aggregate offering price, net of Selling Expenses, of at least $5,000,000, then the Company shall (i) within ten days after the date such request is given, give notice thereof
(the “Demand Notice”) to all Major Holders other than the Initiating Holders; and (ii) as soon as practicable, and in any event within 60 days after the date such request is given by the Initiating Holders, file a Form S-1
registration statement under the Securities Act covering all Registrable Securities that the Initiating Holders requested to be registered and any additional Registrable Securities requested to be included in such registration by any other Major
Holders, as specified by notice given by each such Major Holder to the Company within 20 days of the date the Demand Notice is given, and in each case, subject to the limitations of Section 2.1(c) and Section 2.3. 

(b) Form S-3 Demand. If at any time when it is eligible to use a Form S-3 registration statement, the Company receives a
request from Major Holders of Registrable Securities then outstanding that the Company file a Form S-3 registration statement with respect to outstanding Registrable Securities of such Major Holders having an anticipated aggregate offering price,
net of Selling Expenses, of at least $3,000,000, then the Company shall 

  

					
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(i) within 10 days after the date such request is given, give a Demand Notice to all Major Holders other than the Initiating Holders; and (ii) as soon as practicable, and in any event within
45 days after the date such request is given by the Initiating Holders, file a Form S-3 registration statement under the Securities Act covering all Registrable Securities requested to be included in such registration by any other Major Holders, as
specified by notice given by each such Major Holder to the Company within 20 days of the date the Demand Notice is given, and in each case, subject to the limitations of Section 2.1(c) and Section 2.3. 

(c) Notwithstanding the foregoing obligations, if the Company furnishes to Major Holders requesting a registration pursuant to this
Section 2.1 a certificate signed by the Company’s Chief Executive Officer stating that in the good faith judgment of the Company’s Board of Directors it would be materially detrimental to the Company and its shareholders for
such registration statement to be filed and it is therefore necessary to defer the filing of such registration statement, then the Company shall have the right to defer taking action with respect to such filing, and any time periods with respect to
filing or effectiveness thereof shall be tolled correspondingly, for a period of not more than 105 days after the request of the Initiating Holders is given; provided, however, that the Company may not invoke this right more than once in any
12 month period; and provided further that the Company shall not register any securities for its own account or that of any other shareholder during such 105-day period other than an Excluded Registration. 

(d) The Company shall not be obligated to effect, or to take any action to effect, any registration pursuant to
Section 2.1(a) (i) during the period that is 60 days before the Company’s good faith estimate of the date of filing of, and ending on a date that is 180 days after the effective date of, a Company-initiated registration,
provided, that the Company is actively employing in good faith commercially reasonable efforts to cause such registration statement to become effective; (ii) after the Company has effected three registrations pursuant to
Section 2.1(a); or (iii) 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 2.1(b). The Company
shall not be obligated to effect, or to take any action to effect, any registration pursuant to Section 2.1(b) (i) during the period that is 30 days before the Company’s good faith estimate of the date of filing of, and ending
on a date that is 90 days after the effective date of, a Company-initiated registration, provided, that the Company is actively employing in good faith commercially reasonable efforts to cause such registration statement to become effective; or
(ii) if the Company has effected two registrations pursuant to Section 2.1(b) within the 12 month period immediately preceding the date of such request. A registration shall not be counted as “effected” for purposes of
this Section 2.1(d) until such time as the applicable registration statement has been declared effective by the SEC, unless the Initiating Holders withdraw their request for such registration, elect not to pay the registration expenses
therefor, and forfeit their right to one demand registration statement pursuant to Section 2.6, in which case such withdrawn registration statement shall be counted as “effected” for purposes of this Section 2.1(d).
 
 2.2 Company Registration. If the Company proposes to register (including, for this purpose, a registration
effected by the Company for any shareholder of the Company) any of its securities under the Securities Act in connection with the public offering of such securities solely for cash (other than in an Excluded Registration), the Company shall, at such

  

					
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time, promptly give each Holder notice of such registration. Upon the request of each Holder given within 20 days after such notice is given by the Company, the Company shall, subject to the
provisions of Section 2.3, cause to be registered all of the Registrable Securities that each such Holder has requested to be included in such registration. The Company shall have the right to terminate or withdraw any registration
initiated by it under this Section 2.2 before the effective date of such registration, whether or not any Holder has elected to include Registrable Securities in such registration. The expenses (other than Selling Expenses) of such
withdrawn registration shall be borne by the Company in accordance with Section 2.6. 
 2.3 Underwriting
Requirements. 
 (a) If, pursuant to Section 2.1, 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 Section 2.1, and the Company shall include such information in the Demand Notice. The
underwriter(s) will be selected by the Company and shall be reasonably acceptable to a majority in interest of the Initiating Holders. In such event, the right of any Holder to include such Holder’s 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 (together with the Company as provided in Section 2.4(e)) enter into an underwriting agreement in customary form with the underwriter(s) selected for such underwriting. Notwithstanding any other provision
of this Section 2.3, if the managing underwriter(s) advise(s) the Initiating Holders in writing that marketing factors require a limitation on the number of shares to be underwritten, then the Initiating Holders shall so advise all
Holders of Registrable Securities that otherwise would be underwritten pursuant hereto, and the number of Registrable Securities that may be included in the underwriting shall be allocated among such Holders of Registrable Securities, including the
Initiating Holders, in proportion (as nearly as practicable) to the number of Registrable Securities owned by each Holder or in such other proportion as shall mutually be agreed to by all such selling Holders; provided, however, that the
number of Registrable Securities held by the Holders to be included in such underwriting shall not be reduced unless all other securities are first entirely excluded from the underwriting. 

(b) In connection with any offering involving an underwriting of shares of the Company’s capital stock pursuant to
Section 2.2, the Company shall not be required to include any of the Holders’ Registrable Securities in such underwriting unless the Holders accept the terms of the underwriting as agreed upon between the Company and its
underwriters, and then only in such quantity as the underwriters in their sole discretion determine will not jeopardize the success of the offering by the Company. If the total number of securities, including Registrable Securities, requested by
shareholders to be included in such offering exceeds the number of securities to be sold (other than by the Company) that the underwriters in their reasonable discretion determine is compatible with the success of the offering, then the Company
shall be required to include in the offering only that number of such securities, including Registrable Securities, which the underwriters and the Company in their sole discretion determine will not jeopardize the success of the offering. If the
underwriters determine that less than all of the Registrable Securities requested to be registered can be included in such offering, then, the Registrable Securities that are included in such offering shall be allocated among the

  

					
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selling Holders in proportion (as nearly as practicable to) the number of Registrable Securities owned by each selling Holder or in such other proportions as shall mutually be agreed to by all
such selling Holders. Notwithstanding the foregoing, in no event shall (i) the number of Registrable Securities included in the offering be reduced unless all other securities (other than securities to be sold by the Company) are first entirely
excluded from the offering, or (ii) the number of Registrable Securities included in the offering be reduced below 30% of the total number of securities included in such offering, unless such offering is an IPO, in which case the selling
Holders may be excluded further if the underwriters make the determination described above and no other shareholder’s securities are included in such offering. For purposes of the provision in this Section 2.3(b) concerning
apportionment, for any selling Holder that is a partnership, limited liability company, or corporation, the partners, members, retired partners, retired members, shareholders, and Affiliates of such Holder, or the estates and Immediate Family
Members of any such partners, retired partners, members, and retired members and any trusts for the benefit of any of the foregoing Persons, shall be deemed to be a single “selling Holder,” and any pro rata reduction with respect to such
“selling Holder” shall be based upon the aggregate number of Registrable Securities owned by all Persons included in such “selling Holder,” as defined in this sentence. 

(c) For purposes of Section 2.1, a registration shall not be counted as “effected” if, as a result of an exercise
of the underwriter’s cutback provisions in Section 2.3(a), fewer than 50% of the total number of Registrable Securities that Holders have requested to be included in such registration statement are actually included. 

2.4 Obligations of the Company. Whenever required under this Section 2 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 its commercially 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 a period of up to 120 days or, if earlier, until the distribution contemplated in the registration statement has been completed; provided, however, that (i) such 120 day period
shall be extended for a period of time equal to the period the Holder refrains, at the request of an underwriter of Common Stock (or other securities) of the Company, from selling any securities included in such registration, and (ii) in the
case of any registration of Registrable Securities on Form S-3 that are intended to be offered on a continuous or delayed basis, subject to compliance with applicable SEC rules, such 120 day period shall be extended for up to one year, if necessary,
to keep the registration statement effective until all such Registrable Securities are sold; 
 (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 Securities Act in order to enable the disposition of all securities
covered by such registration statement; 
 (c) furnish to the selling Holders such numbers of copies of a prospectus, including
a preliminary prospectus, as required by the Securities Act, and such other 

  

					
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documents as the Holders may reasonably request in order to facilitate their disposition of their Registrable Securities; 

(d) use its commercially reasonable efforts to register and qualify the securities covered by such registration statement under such
other securities or blue-sky laws of such jurisdictions as shall be reasonably requested by the selling Holders; provided that the Company shall not be required to qualify to do business or to file a general consent to service of process in
any such states or jurisdictions, unless the Company is already subject to service in such jurisdiction and except as may be required by the Securities Act; 
 (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 underwriter(s) of such offering;

 (f) use its commercially reasonable efforts to cause all such Registrable Securities covered by such registration statement
to be listed on a national securities exchange or trading system and each securities exchange and trading system (if any) on which similar securities issued by the Company are then listed; 

(g) provide a transfer agent and registrar for all Registrable Securities registered pursuant to this Agreement and provide a CUSIP
number for all such Registrable Securities, in each case not later than the effective date of such registration; 
 (h)
promptly make available for inspection by the selling Holders, any managing underwriter(s) participating in any disposition pursuant to such registration statement, and any attorney or accountant or other agent retained by any such underwriter or
selected by the selling Holders, all financial and other records, pertinent corporate documents, and properties of the Company, and cause the Company’s officers, directors, employees, and independent accountants to supply all information
reasonably requested by any such seller, underwriter, attorney, accountant, or agent, in each case, as necessary or advisable to verify the accuracy of the information in such registration statement and to conduct appropriate due diligence in
connection therewith; 
 (i) notify each selling Holder, promptly after the Company receives notice thereof, of the time when
such registration statement has been declared effective or a supplement to any prospectus forming a part of such registration statement has been filed; and 
 (j) after such registration statement becomes effective, notify each selling Holder of any request by the SEC that the Company amend or supplement such registration statement or prospectus. 

2.5 Furnish Information. It shall be a condition precedent to the obligations of the Company to take any action pursuant to this
Section 2 with respect to the Registrable Securities of any selling Holder that such Holder shall furnish to the Company such information regarding itself, the Registrable Securities held by it, and the intended method of disposition of
such securities as is reasonably required to effect the registration of such Holder’s Registrable Securities. 

  

					
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 2.6 Expenses of Registration. All expenses (other than Selling Expenses) incurred in
connection with registrations, filings, or qualifications pursuant to Section 2, including all registration, filing, and qualification fees; printers’ and accounting fees; fees and disbursements of counsel for the Company; and the
reasonable fees and disbursements, not to exceed $50,000 of one counsel for the selling Holders (“Selling Holder Counsel”), shall be borne and paid by the Company; provided, however, that the Company shall not be required to
pay for any expenses of any registration proceeding begun pursuant to Section 2.1 if the registration request is subsequently withdrawn at the request of the Holders of a majority of the Registrable Securities to be registered (in which
case all selling Holders shall bear such expenses pro rata based upon the number of Registrable Securities that were to be included in the withdrawn registration), unless the Holders of a majority of the Registrable Securities agree to forfeit their
right to one registration pursuant to Section 2.1(a) or Section 2.1(b), as the case may be; provided further that if, at the time of such withdrawal, the Holders shall have learned of a material adverse change in the
condition, business, or prospects of the Company from that known to the Holders at the time of their request and have withdrawn the request with reasonable promptness after learning of such information then the Holders shall not be required to pay
any of such expenses and shall not forfeit their right to one registration pursuant to Section 2.1(a) or Section 2.1(b). All Selling Expenses relating to Registrable Securities registered pursuant to this
Section 2 shall be borne and paid by the Holders pro rata on the basis of the number of Registrable Securities registered on their behalf. 
 2.7 Delay of Registration. No Holder shall have any right to obtain or seek an injunction restraining or otherwise delaying any registration pursuant to this Agreement as the result of any
controversy that might arise with respect to the interpretation or implementation of this Section 2. 
 2.8
Indemnification. If any Registrable Securities are included in a registration statement under this Section 2: 
 (a) To the extent permitted by law, the Company will indemnify and hold harmless each selling Holder, and the partners, members, officers, directors, and shareholders of each such Holder; legal counsel
and accountants for each such Holder; any underwriter (as defined in the Securities Act) for each 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
Damages, and the Company will pay to each such Holder, underwriter, controlling Person, or other aforementioned Person any legal or other expenses reasonably incurred thereby in connection with investigating or defending any claim or proceeding from
which Damages may result, as such expenses are incurred; provided, however, that the indemnity agreement contained in this Section 2.8(a) shall not apply to amounts paid in settlement of any such claim or proceeding if such
settlement is effected without the consent of the Company, which consent shall not be unreasonably withheld, nor shall the Company be liable for any Damages to the extent that they arise out of or are based upon actions or omissions made in reliance
upon and in conformity with written information furnished by or on behalf of any such Holder, underwriter, controlling Person, or other aforementioned Person expressly for use in connection with such registration. 

  

					
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 (b) To the extent permitted by law, each selling Holder, severally and not jointly, will
indemnify and hold harmless the Company, and each of its directors, each of its officers who has signed the registration statement, each Person (if any), who controls the Company within the meaning of the Securities Act, legal counsel and
accountants for the Company, any underwriter (as defined in the Securities Act), any other Holder selling securities in such registration statement, and any controlling Person of any such underwriter or other Holder, against any Damages, in each
case only to the extent that such Damages arise out of or are based upon actions or omissions made in reliance upon and in conformity with written information furnished by or on behalf of such selling Holder expressly for use in connection with such
registration; and each such selling Holder will pay to the Company and each other aforementioned Person any legal or other expenses reasonably incurred thereby in connection with investigating or defending any claim or proceeding from which Damages
may result, as such expenses are incurred; provided, however, that the indemnity agreement contained in this Section 2.8(b) shall not apply to amounts paid in settlement of any such claim or proceeding if such settlement is
effected without the consent of the Holder, which consent shall not be unreasonably withheld; and provided further that in no event shall the aggregate amounts payable by any Holder by way of indemnity or contribution under Sections 2.8(b)
and 2.8(d) exceed the proceeds from the offering received by such Holder (net of any Selling Expenses paid by such Holder), except in the case of fraud or willful misconduct 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) for which a party may be entitled to indemnification hereunder, such indemnified party will, if a claim in respect thereof is to be made against any indemnifying party under this Section 2.8, give the
indemnifying party notice of the commencement thereof. The indemnifying party shall have the right to participate in such action and, to the extent the indemnifying party so desires, participate jointly with any other indemnifying party to which
notice has been given, and to assume the defense thereof with counsel mutually satisfactory to the parties; provided, however, that an indemnified party (together with all other indemnified parties that may be represented without conflict by
one counsel) shall have the right to retain one separate 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 action. The failure to give 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, except to the extent that such failure materially prejudices the indemnifying party’s ability to defend the action. 

(d) To provide for just and equitable contribution to joint liability under the Securities Act in any case in which either (i) any
party otherwise entitled to indemnification hereunder makes a claim for indemnification pursuant to this Section 2.8 but it is judicially determined (by the entry of a final judgment or decree by a court of competent jurisdiction and the
expiration of time to appeal or the denial of the last right of appeal) that such indemnification may not be enforced in such case, notwithstanding the fact that this Section 2.8 provides for indemnification in such case, or
(ii) contribution under the Securities Act may be required on the part of any party hereto for which indemnification is provided under this Section 2.8, then, and in each such case, such parties will contribute to the aggregate
losses, 

  

					
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claims, damages, liabilities, or expenses to which they may be subject (after contribution from others) in such proportion as is appropriate to reflect the relative fault of each of the
indemnifying party and the indemnified party in connection with the statements, omissions, or other actions that resulted in such loss, claim, damage, liability, or expense, as well as to reflect any other relevant equitable considerations. The
relative fault of the indemnifying party and of the indemnified party shall be determined by reference to, among other things, whether the untrue or allegedly untrue statement of a material fact, or the omission or alleged omission of 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,
however, that, in any such case, (x) no Holder will be required to contribute any amount in excess of the public offering price of all such Registrable Securities offered and sold by such Holder pursuant to such registration statement, and
(y) no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) will be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation; and provided
further that in no event shall a Holder’s liability pursuant to this Section 2.8(d), when combined with the amounts paid or payable by such Holder pursuant to Section 2.8(b), exceed the proceeds from the offering
received by such Holder (net of any Selling Expenses paid by such Holder), except in the case of willful misconduct or fraud by such Holder. 
 (e) Notwithstanding the foregoing, to the extent that the provisions on indemnification and contribution contained in the underwriting agreement entered into in connection with the underwritten public
offering are in conflict with the foregoing provisions, the provisions in the underwriting agreement shall control. 
 (f)
Unless otherwise superseded by an underwriting agreement entered into in connection with the underwritten public offering, the obligations of the Company and Holders under this Section 2.8 shall survive the completion of any offering of
Registrable Securities in a registration under this Section 2, and otherwise shall survive the termination of this Agreement. 
 2.9 Reports Under Exchange Act. With a view to making available to the Holders the benefits of SEC Rule 144 and any other rule or regulation of the SEC that may at any time permit a Holder to sell
securities of the Company to the public without registration or pursuant to a registration on Form S-3, the Company shall: 

(a) make and keep available adequate current public information, as those terms are understood and defined in SEC Rule 144, at all times
after the effective date of the registration statement filed by the Company for an IPO; 
 (b) use commercially reasonable
efforts to file with the SEC in a timely manner all reports and other documents required of the Company under the Securities Act and the Exchange Act (at any time after the Company has become subject to such reporting requirements); and 

(c) furnish to any Holder, so long as the Holder owns any Registrable Securities, forthwith upon request (i) to the extent
accurate, a written statement by the Company 

  

					
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that it has complied with the reporting requirements of SEC Rule 144 (at any time after 90 days after the effective date of the registration statement filed by the Company for an IPO), the
Securities Act, and the Exchange Act (at any time after the Company has become subject to such reporting requirements), or that it qualifies as a registrant whose securities may be resold pursuant to Form S-3 (at any time after the Company
so qualifies); (ii) a copy of the most recent annual or quarterly report of the Company and such other reports and documents so filed by the Company; and (iii) such other information as may be reasonably requested in availing any Holder of
any rule or regulation of the SEC that permits the selling of any such securities without registration (at any time after the Company has become subject to the reporting requirements under the Exchange Act) or pursuant to Form S-3 (at any time after
the Company so qualifies to use such form). 
 2.10 Limitations on Subsequent Registration Rights. From and 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 (i) would allow such holder or prospective holder to include such securities in any registration unless, under the terms of such agreement, such holder or prospective holder may include such securities in any such registration only
to the extent that the inclusion of such securities will not reduce the number of the Registrable Securities of the Holders that are included, or (ii) would allow such holder or prospective holder to initiate a demand for registration of any
securities held by such holder or prospective holder; provided that this limitation shall not apply to any additional Investor who becomes a party to this Agreement in accordance with Section 7.9. 

2.11 “Market Stand-off” Agreement. Each Holder hereby agrees that it will not, without the prior written consent of the
managing underwriter, during the period commencing on the date of the final prospectus relating to the registration by the Company of shares of its Common Stock or any other equity securities under the Securities Act on a registration statement on
Form S-1 and ending on the date specified by the Company and the managing underwriter (such period not to exceed 180 days), (i) lend; offer; pledge; sell; contract to sell; sell any option or contract to purchase; purchase any option or
contract to sell; grant any option, right, or warrant to purchase; or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable (directly or indirectly) for
Common Stock held immediately before the effective date of the registration statement for such offering or (ii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of
ownership of such securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or other securities, in cash, or otherwise. The foregoing provisions of this
Section 2.11 shall apply only to an IPO, shall not apply to the sale of any shares to an underwriter pursuant to an underwriting agreement, and shall be applicable to the Holders only if all officers and directors of the Company are
subject to the same restrictions. The underwriters in connection with such registration are intended third-party beneficiaries of this Section 2.11 and shall have the right, power, and authority to enforce the provisions hereof as though
they were a party hereto. Each Holder further agrees to execute such agreements as may be reasonably requested by the underwriters in connection with such registration that are consistent with this Section 2.11 or that are necessary to
give further effect thereto. Any discretionary waiver or termination of the restrictions of any or all of such agreements by the Company or the 

  

					
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underwriters shall apply pro rata to all Holders subject to such agreements, based on the number of shares subject to such agreements, except that, notwithstanding the foregoing, the Company and
the underwriters may, in their sole discretion, waive or terminate these restrictions with respect to up to 1,000 shares of the Common Stock. 
 2.12 Restrictions on Transfer. 
 (a) The Series A Preferred Stock and
the Registrable Securities shall not be sold, pledged, or otherwise transferred, and the Company shall not recognize and shall issue stop-transfer instructions to its transfer agent with respect to any such sale, pledge, or transfer, except upon the
conditions specified in this Section 2.12, which conditions are intended to ensure compliance with the provisions of the Securities Act. A transferring Holder will cause any proposed purchaser, pledgee, or transferee of the Series A
Preferred Stock and the Registrable Securities held by such Holder to agree to take and hold such securities subject to the provisions and upon the conditions specified in this Section 2.12. 

(b) Each certificate or instrument representing (i) the Series A Preferred Stock, (ii) the Registrable Securities, and
(iii) any other securities issued in respect of the securities referenced in clauses (i) and (ii), upon any stock split, stock dividend, recapitalization, merger, consolidation, or similar event, shall (unless otherwise permitted by
the provisions of Section 2.12(c)) be stamped or otherwise imprinted with a legend substantially in the following form: 
 THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE
SALE OR DISTRIBUTION THEREOF. NO SUCH TRANSFER MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED. 
 THE SECURITIES REPRESENTED HEREBY MAY BE TRANSFERRED ONLY IN ACCORDANCE WITH THE TERMS OF AN AGREEMENT
BETWEEN THE COMPANY AND THE SHAREHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY. 
 The Holders consent to the Company
making a notation in its records and giving instructions to any transfer agent of the Restricted Securities in order to implement the restrictions on transfer set forth in this Section 2.12. 

(c) The holder of each certificate representing Restricted Securities, by acceptance thereof, agrees to comply in all respects with the
provisions of this Section 2. Before any proposed sale, pledge, or transfer of any Restricted Securities, unless there is in effect a registration statement under the Securities Act covering the proposed transaction, the Holder thereof
shall give notice to the Company of such Holder’s intention to effect such sale, pledge, or 

  

					
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transfer. Each such notice shall describe the manner and circumstances of the proposed sale, pledge, or transfer in sufficient detail and, if reasonably requested by the Company, shall be
accompanied at such Holder’s expense by either (i) a written opinion of legal counsel who shall, and whose legal opinion shall, be reasonably satisfactory to the Company, addressed to the Company, to the effect that the proposed
transaction may be effected without registration under the Securities Act; (ii) a “no action” letter from the SEC to the effect that the proposed sale, pledge, or transfer of such Restricted Securities without registration will not
result in a recommendation by the staff of the SEC that action be taken with respect thereto; or (iii) any other evidence reasonably satisfactory to counsel to the Company to the effect that the proposed sale, pledge, or transfer of the
Restricted Securities may be effected without registration under the Securities Act, whereupon the Holder of such Restricted Securities shall be entitled to sell, pledge, or transfer such Restricted Securities in accordance with the terms of the
notice given by the Holder to the Company. The Company will not require such a legal opinion or “no action” letter (x) in any transaction in compliance with SEC Rule 144, (y) in any transaction in which such Holder transfers
Restricted Securities to an Affiliate of such Holder for no consideration, or (z) in any transaction in which an individual Holder transfers Restricted Securities to such Holder’s Immediate Family Member or trust for the benefit of an
individual Holder or one or more of such Holder’s Immediate Family Members; provided that each transferee agrees in writing to be subject to the terms of this Section 2.12. Each certificate or instrument evidencing the Restricted
Securities transferred as above provided shall bear, except if such transfer is made pursuant to SEC Rule 144, the appropriate restrictive legend set forth in Section 2.12(b), except that such certificate shall not bear such
restrictive legend if, in the opinion of counsel for such Holder and the Company, such legend is not required in order to establish compliance with any provisions of the Securities Act. 

2.13 [Intentionally Omitted.] 
 2.14 Termination of Registration Rights. The right of any Holder to request registration or inclusion of Registrable Securities in any registration pursuant to Section 2.1 or
Section 2.2 shall terminate upon the earliest to occur of: 
 (a) the closing of a Deemed Liquidation Event, as
such term is defined in the Company’s Amended and Restated Articles of Incorporation; 
 (b) the date on which all shares
of Registrable Securities held by such Holder may be sold under Rule 144 within a 90 day period for any continuous 180 day period; and 
 (c) the fifth anniversary of the date of the IPO. 
  

	 	3.	Information Rights. 

 3.1
Delivery of Financial Statements. The Company shall deliver to each Major Investor: 
 (a) as soon as practicable, but
in any event within 150 days after the end of each fiscal year of the Company (and no later than when provided to the Company’s lenders), (i) a balance sheet as of the end of such year, (ii) statements of income and of cash

  

					
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	  	 	Page 14	  

 
flows for such year, and a comparison between (x) the actual amounts as of and for such fiscal year and (y) the comparable amounts for the prior year and as included in the Budget (as
defined in Section 3.1(d)) for such year, with an explanation of any material differences between such amounts and a schedule as to the sources and applications of funds for such year, and (iii) a statement of shareholders’
equity as of the end of such year, with the financial statements audited and certified by independent public accountants selected by the Company; 
 (b) as soon as practicable, but in any event within 45 days after the end of each of the first three quarters of each fiscal year of the Company, unaudited statements of income and of cash flows for such
fiscal quarter, and an unaudited balance sheet as of the end of such fiscal quarter, all prepared in accordance with GAAP (except that such financial statements may (i) be subject to normal year-end audit adjustments and (ii) not contain
all notes thereto that may be required in accordance with GAAP); 
 (c) as soon as practicable, but in any event within 45 days
after the end of each of the first three quarters of each fiscal year of the Company, a statement showing the number of shares of each class and series of capital stock and securities convertible into or exercisable for shares of capital stock
outstanding at the end of the period, the Common Stock issuable upon conversion or exercise of any outstanding securities convertible or exercisable for Common Stock and the exchange ratio or exercise price applicable thereto, and the number of
shares of issued stock options and stock options not yet issued but reserved for issuance, if any, all in sufficient detail as to permit the Major Investors to calculate their respective percentage equity ownership in the Company, and certified by
the chief financial officer or chief executive officer of the Company as being true, complete, and correct; 
 (d) as soon as
practicable, but in any event within 30 days of the end of each month, an unaudited income statement and statement of cash flows for such month, and an unaudited balance sheet as of the end of such month, all prepared in accordance with GAAP (except
that such financial statements may (i) be subject to normal year-end audit adjustments and (ii) not contain all notes thereto that may be required in accordance with GAAP); 

(e) as soon as practicable, but in any event 30 days after the start of each fiscal year, a budget and business plan for that fiscal
year (collectively, the “Budget”), approved by the Board of Directors and prepared on a monthly basis, including balance sheets, income statements, and statements of cash flow for such months and, promptly after prepared, any other
budgets or revised budgets prepared by the Company; and 
 (f) such other information relating to the financial condition,
business, prospects, or corporate affairs of the Company as any Major Investor may from time to time reasonably request; provided, however, that the Company shall not be obligated under this Section 3.1 to provide information
(i) that the Company reasonably determines in good faith to be a trade secret or confidential information (unless covered by an enforceable confidentiality agreement, in form acceptable to the Company) or (ii) the disclosure of which would
adversely affect the attorney-client privilege between the Company and its counsel. 
 If, for any period, the Company has any subsidiary whose
accounts are consolidated with those of the Company, then in respect of such period the financial statements delivered pursuant to the 

  

					
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foregoing sections shall be the consolidated and consolidating financial statements of the Company and all such consolidated subsidiaries. 

Notwithstanding anything else in this Section 3.1 to the contrary, the Company may cease providing the information set forth in this
Section 3.1 during the period starting with the date 30 days before the Company’s good-faith estimate of the date of filing of a registration statement if it reasonably concludes it must do so to comply with the SEC rules applicable
to such registration statement and related offering; provided that the Company’s covenants under this Section 3.1 shall be reinstated at such time as the Company is no longer actively employing its commercially reasonable efforts to
cause such registration statement to become effective. 
 3.2 Inspection. The Company shall permit each Major Investor,
at such Major Investor’s expense, to visit and inspect the Company’s properties; examine its books of account and records; and discuss the Company’s affairs, finances, and accounts with its officers, during normal business hours of
the Company as may be reasonably requested by the Major Investor; provided, however, that the Company shall not be obligated pursuant to this Section 3.2 to provide access to any information that it reasonably and in good faith
considers to be a trade secret or confidential information (unless covered by an enforceable confidentiality agreement, in form acceptable to the Company) or the disclosure of which would adversely affect the attorney-client privilege between the
Company and its counsel. 
 3.3 Termination of Information Rights. The covenants set forth in Section 3.1 and
Section 3.2 shall terminate and be of no further force or effect (i) immediately before the consummation of a Qualified IPO or (ii) upon a Deemed Liquidation Event, whichever event occurs first. 

3.4 Confidentiality. Each Investor agrees that such Investor will keep confidential and will not disclose, divulge, or use for any
purpose (other than to monitor its investment in the Company) any confidential information obtained from the Company pursuant to the terms of this Agreement (including notice of the Company’s intention to file a registration statement), unless
such confidential information (a) is known or becomes known to the public in general (other than as a result of a breach of this Section 3.4 by such Investor), (b) is or has been independently developed or conceived by the
Investor without use of the Company’s confidential information, or (c) is or has been made known or disclosed to the Investor by a third party without a breach of any obligation of confidentiality such third party may have to the Company;
provided, however, that an Investor may disclose confidential information (i) to its attorneys, accountants, consultants, and other professionals to the extent necessary to obtain their services in connection with monitoring its
investment in the Company; (ii) to any prospective purchaser of any Registrable Securities from such Investor, if such prospective purchaser agrees to be bound by the provisions of this Section 3.4; (iii) to any existing or
prospective Affiliate, partner, member, shareholder, or wholly owned subsidiary of such Investor in the ordinary course of business, provided that such Investor informs such Person that such information is confidential and directs such Person
to maintain the confidentiality of such information; or (iv) as may otherwise be required by law, provided that the Investor promptly notifies the Company of such disclosure and takes reasonable steps to minimize the extent of any such
required disclosure. 

  

					
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	 	4.	Rights to Future Stock Issuances. 

 4.1 Right of First Offer. Subject to the terms and conditions of this Section 4.1 and applicable securities laws, if the Company proposes to offer or sell any New Securities, the
Company shall first offer such New Securities to each Major Investor. A Major Investor shall be entitled to apportion the right of first offer hereby granted to it among itself and its Affiliates in such proportions as it deems appropriate.

 (a) The Company shall give notice (the “Offer Notice”) to each Major Investor, stating (i) its bona
fide intention to offer such New Securities, (ii) the number of such New Securities to be offered, and (iii) the price and terms, if any, upon which it proposes to offer such New Securities. 

(b) By notification to the Company within 20 days after the Offer Notice is given, each Major Investor may elect to purchase or
otherwise acquire, at the price and on the terms specified in the Offer Notice, up to that portion of such New Securities that equals the proportion that the Common Stock issued and held, or issuable (directly or indirectly) upon conversion and/or
exercise, as applicable, of the Series A Preferred Stock and any other Derivative Securities then held, by such Major Investor bears to the total Common Stock of the Company then outstanding (assuming full conversion and/or exercise, as applicable,
of all Series A Preferred Stock and other Derivative Securities). At the expiration of such 20 day period, the Company shall promptly notify each Major Investor that elects to purchase or acquire all the shares available to it (each, a
“Fully Exercising Investor”) of any other Major Investor’s failure to do likewise. During the ten day period commencing after the Company has given such notice, each Fully Exercising Investor may, by giving notice to the
Company, elect to purchase or acquire, in addition to the number of shares specified above, up to that portion of the New Securities for which Major Investors were entitled to subscribe but that were not subscribed for by the Major Investors which
is equal to the proportion that the Common Stock issued and held, or issuable (directly or indirectly) upon conversion and/or exercise, as applicable, of Series A Preferred Stock and any other Derivative Securities then held, by such Fully
Exercising Investor bears to the Common Stock issued and held, or issuable (directly or indirectly) upon conversion and/or exercise, as applicable, of the Series A Preferred Stock and any other Derivative Securities then held, by all Fully
Exercising Investors who wish to purchase such unsubscribed shares. The closing of any sale pursuant to this Section 4.1(b) shall occur within the later of 90 days of the date that the Offer Notice is given and the date of initial sale
of New Securities pursuant to Section 4.1(c). 
 (c) If all New Securities referred to in the Offer Notice are not
elected to be purchased or acquired as provided in Section 4.1(b), the Company may, during the 90 day period following the expiration of the periods provided in Section 4.1(b), offer and sell the remaining unsubscribed
portion of such New Securities to any Person or Persons at a price not less than, and upon terms no more favorable to the offeree than, those specified in the Offer Notice. If the Company does not enter into an agreement for the sale of the New
Securities within such period, or if such agreement is not consummated within the later of such 90 day period or 30 days of the execution thereof, the right provided hereunder shall be deemed to be revived and such New Securities shall not be
offered unless first reoffered to the Major Investors in accordance with this Section 4.1. 

  

					
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 (d) The right of first offer in this Section 4.1 shall not be applicable to the
following: (i) securities (including options to purchase shares of Common Stock) issued or issuable to Company management or personnel under the Company’s 2000 Stock Option Plan, as amended, and under any replacement or successor plan
approved by the Board of Directors and the Company’s shareholders; (ii) securities issued in connection with a debt financing, acquisition or strategic transaction approved by the Board of Directors; (iii) securities issued upon
conversion of any of the Series A Preferred Stock, or as a dividend or distribution on the Series A Preferred Stock; (iv) securities issued upon the conversion of any warrant, option, or other convertible security approved by the Board of
Directors and outstanding as of the date of this Agreement; (v) securities issuable upon a stock split, stock dividend, or any subdivision of shares of Common Stock; (vi) any right, option or warrant to acquire any security convertible
into the securities covered by the foregoing; and (vii) shares of Common Stock issued in an IPO. 
 (e) Notwithstanding
any provision hereof to the contrary, in lieu of complying with the provisions of this Section 4.1, the Company may elect to give notice to the Major Investors within 30 days after the issuance of New Securities. Such notice shall
describe the type, price, and terms of the New Securities. Each Major Investor shall have 20 days from the date notice is given to elect to purchase up to the number of New Securities that would, if purchased by such Major Investor, maintain such
Major Investor’s percentage-ownership position, calculated as set forth in Section 4.1(b) before giving effect to the issuance of such New Securities. The closing of such sale shall occur within 60 days of the date notice is given
to the Major Investors. 
 4.2 Termination. The covenants set forth in Section 4.1 shall terminate and be of
no further force or effect (i) immediately before the consummation of an IPO or (ii) upon a Deemed Liquidation Event, whichever event occurs first. 
  

	 	5.	Additional Covenants. 

5.1 Insurance. The Company shall use its commercially reasonable efforts to obtain, within 90 days of the date hereof, from
financially sound and reputable insurers term “key-person” insurance on Larry Lukis and Brad Cleveland, each in an amount of $2.5 million and on terms and conditions satisfactory to the Board of Directors, and will use commercially
reasonable efforts to cause such insurance policies and its existing Directors and Officers liability insurance to be maintained until such time as the Board of Directors determines that such insurance should be discontinued. The key-person policy
shall name the Company as loss payee, and neither policy shall be cancelable by the Company without prior approval by the Board of Directors. 
 5.2 Employee Agreements. The Company will use reasonable efforts to obtain from each (i) senior manager and software developer now or hereafter employed by it or by any subsidiary (or engaged
by the Company or any subsidiary as a consultant/independent contractor) with access to confidential information and/or trade secrets to enter into a nondisclosure and proprietary rights assignment agreement and (ii) Key Employee to enter into
a non-competition and non-solicitation agreement, substantially in the form approved by the Board of Directors. In addition, the Company shall not amend, modify, terminate, waive, or otherwise alter, in whole or in part, any of the above-referenced
agreements or any restricted stock 

  

					
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	  	 	Page 18	  

 
agreement between the Company and any employee, without the consent of the Board of Directors. 
 5.3 Board Matters. Unless otherwise determined by the vote of a majority of the directors then in office, the Board of Directors shall meet at least quarterly in accordance with an agreed-upon
schedule. The Company shall reimburse the nonemployee directors for all reasonable out-of-pocket travel expenses incurred (consistent with the Company’s travel policy) in connection with attending meetings of the Board of Directors. The Company
will maintain an audit and compensation committee, each of which shall consist solely of non-management directors. Each non-employee director shall be entitled in such person’s discretion to be a member of any Board committee. Any future
increase to Larry Lukis’ compensation must be approved by the Company’s compensation committee.
 5.4 Successor
Indemnification. If the Company or any of its successors or assignees consolidates with or merges into any other Person and is not the continuing or surviving corporation or entity of such consolidation or merger, then to the extent necessary,
proper provision shall be made so that the successors and assignees of the Company assume the obligations of the Company with respect to indemnification of members of the Board of Directors as in effect immediately before such transaction, whether
such obligations are contained in the Company’s By-laws, its Articles of Incorporation, or elsewhere, as the case may be. 

5.5 Termination of Covenants. The covenants set forth in this Section 5, except for Section 5.4, shall
terminate and be of no further force or effect (i) immediately before the consummation of the IPO or (ii) when the Company first becomes subject to the periodic reporting requirements of Section 12(g) or 15(d) of the Exchange Act, or
(iii) upon a Deemed Liquidation Event, whichever event occurs first. 
  

	 	6.	Put Right. 

 6.1
Put. PIC shall have the right to tender all or any portion of its Registrable Securities to the Company and the Company shall be obligated to purchase and redeem such Registrable Securities so tendered (to the extent that funds are legally
available for redemption), provided that PIC shall not tender less than 10,000 shares of Registrable Securities (subject to adjustment for stock dividends, stock combinations, reorganizations and similar events) on any one occasion upon PIC’s
exercise of its put right pursuant to Section 6.2 below. 
 6.2 Notice of Exercise. PIC may exercise its put
option under Section 6.1 at any time after August 2, 2018. Notice of exercise of the put option shall be given to the Company in writing pursuant to the notice provisions set forth in this Agreement, and shall specify the number of
shares of Registrable Securities being tendered to the Company for sale. 
 6.3 Purchase Price. The purchase price for
shares of Registrable Securities tendered to the Company pursuant to this Section 6 shall be determined as follows: upon receipt of by the Company of PIC’s notice of election to exercise the put option pursuant to
Section 6.2, PIC and an authorized representative of the Company shall meet and attempt in good faith to agree upon the purchase price applicable to the redemption of shares of Registrable Securities

  

					
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under this Section 6. If the parties fail to agree upon such purchase price within 30 days after the Company’s receipt of PIC’s notice of election to exercise its put
option, the purchase price shall be determined by an independent appraisal without discount for lack of liquidity, control or marketability. The appraised fair market value of the shares of Registrable Securities shall be determined as of the last
day of the fiscal year during which the right to put Shares becomes exercisable. The appraisal shall be prepared by a qualified appraiser selected by the Company and acceptable to PIC, with the fees and expenses of the qualified appraisal being
split equally between the Company and PIC. If PIC and the Company cannot agree upon a qualified appraiser, then each party shall select its own qualified appraiser and each appraiser shall separately determine the fair market value of the shares of
Registrable Securities. The purchase price in such case shall be the average of the two appraisals and each party shall bear the costs of their own qualified appraiser. The purchase price determined by the appraiser, or the average of the prices
determined by the two appraisers, as applicable, shall be final and binding upon PIC and the Company. 
 6.4 Payment. The
closing of the sale and redemption of shares under this Section 6 shall occur on a reasonable date, at a reasonable place and at a reasonable time to be agreed among the parties, which shall be no later than forty-five (45) days
after the Company’s receipt of PIC’s notice of election to exercise its put option or fifteen days following the determination of the purchase price, whichever is later. PIC shall be entitled to interest on the purchase price for the
shares at the prevailing prime rate published in The Wall Street Journal from the date of the Company’s receipt of PIC’s notice of election to exercise its put option. 

6.5 Inability to Redeem. If the Company’s funds legally available for redemption of capital stock are insufficient to
discharge in full the Company’s obligations to redeem shares which the Company is then obligated to redeem pursuant to this Section 6, the Company shall redeem the maximum number of shares for which it has sufficient funds. PIC
shall receive interest (“Redemption Interest”) on the aggregate purchase price of the unredeemed shares at a rate per annum equal to 2% in excess of the prevailing prime rate published in The Wall Street Journal. Such
Redemption Interest shall accrue commencing on the date the Company would have otherwise been obligated to redeem the subject shares and shall be payable quarterly in arrears. When additional funds of the Company are legally available for the
redemption of capital stock of the Company, such funds shall be immediately used (i) to redeem the balance of the shares which it has not redeemed (in the manner described in the immediately preceding sentence), and (ii) to pay the
Redemption Interest. 
 6.6 Termination. The rights and covenants set forth in this Section 6 shall terminate
and be of no further force or effect immediately before the consummation of an IPO. 
  

	 	7.	Miscellaneous. 

 7.1
Successors and Assigns. The rights under this Agreement may be assigned (but only with all related obligations) by a Holder to a transferee of Registrable Securities that (i) is an Affiliate of a Holder; (ii) is a Holder’s
Immediate Family Member or trust for the benefit of an individual Holder or one or more of such Holder’s Immediate Family Members; or (iii) after such transfer, holds at least 150,000 shares of Registrable Securities (subject to
appropriate adjustment for stock splits, stock dividends, combinations, and other 

  

					
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recapitalizations); provided, however, that (x) the Company is, within a reasonable time after such transfer, furnished with written notice of the name and address of such transferee and the
Registrable Securities with respect to which such rights are being transferred; and (y) such transferee agrees in a written instrument delivered to the Company to be bound by and subject to the terms and conditions of this Agreement, including
the provisions of Section 2.11. For the purposes of determining the number of shares of Registrable Securities held by a transferee, the holdings of a transferee (1) that is an Affiliate or shareholder of a Holder; (2) who is a
Holder’s Immediate Family Member; or (3) that is a trust for the benefit of an individual Holder or such Holder’s Immediate Family Member shall be aggregated together and with those of the transferring Holder; provided further that
all transferees who would not qualify individually for assignment of rights shall have a single attorney-in-fact for the purpose of exercising any rights, receiving notices, or taking any action under this Agreement. The terms and conditions of this
Agreement inure to the benefit of and are binding upon the respective successors and permitted assignees of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their
respective successors and permitted assignees any rights, remedies, obligations or liabilities under or by reason of this Agreement, except as expressly provided herein. 
 7.2 Governing Law. This Agreement shall be governed by, and construed in accordance with, the laws of the State of Minnesota, regardless of the laws that might otherwise govern under applicable
principles of conflicts of law. The parties hereto agree that any action brought by any party under or in relation to this Agreement, including without limitation to interpret or enforce any provision of this Agreement, shall be brought subject to
the non-exclusive jurisdiction and venue of any state or federal court located in Minnesota. The parties hereby irrevocably waive, to the fullest extent permitted by applicable law, any objection which they may now or hereafter have to the laying of
venue of any such dispute brought in such court or any defense of inconvenient forum for the maintenance of such dispute. Each party agrees that a final judgment in any action or proceeding so brought shall be conclusive and may be enforced by suit
on the judgment or in any other manner provided by law or at equity. 
 7.3 Counterparts; Facsimile. This Agreement may
be executed and delivered by facsimile signature and in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. 

7.4 Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be
considered in construing or interpreting this Agreement. 
 7.5 Notices. All notices and other communications given or
made pursuant to this Agreement shall be in writing and shall be deemed effectively given upon the earlier of actual receipt or: (i) personal delivery to the party to be notified, (ii) when sent, if sent by electronic mail or facsimile
during normal business hours of the recipient, and if not sent during normal business hours, then on the recipient’s next business day, (iii) five days after having been sent by registered or certified mail, return receipt requested,
postage prepaid, or (iv) one business day after the business day of deposit with a nationally recognized overnight courier, freight prepaid, specifying next business day delivery, with written verification of receipt. All communications shall
be sent to the respective parties at their address as set forth on Schedule A  

  

					
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	 	Page 21	  

 
hereto, or to the principal office of the Company and to the attention of the Chief Executive Officer, in the case of the Company, or to such email address, facsimile number or address as
subsequently modified by written notice given in accordance with this Section 7.5. If notice is given to the Company, a copy shall also be sent to Faegre & Benson LLP, 2200 Wells Fargo Center, 90 South Seventh Street,
Minneapolis, MN 55402, Attention: Mark D. Pihlstrom, and if notice is given to the Major Holders, a copy shall also be given to Weil, Gotshal & Manges LLP, 100 Federal Street, Floor 34, Boston, MA 02110, Attention: Kevin J. Sullivan, and to
Briggs and Morgan, Professional Association, 2200 IDS Center, 80 South 8th Street, Minneapolis, MN 55402, Attention: Steve Kozachok. 
 7.6
Amendments and Waivers. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived (either generally or in a particular instance, and either retroactively or prospectively) only with the written
consent of the Company and each Investor; provided that the Company may in its sole discretion waive compliance with Section 2.12(c) (and the Company’s failure to object promptly in writing after notification of a proposed
assignment allegedly in violation of Section 2.12(c) shall be deemed to be a waiver); and provided further that any provision hereof may be waived by any waiving party on such party’s own behalf, without the consent of any other
party. Notwithstanding the foregoing, neither PIC’s nor any Management Investor’s consent to any amendment or waiver shall be required if such amendment or waiver does not adversely affect PIC or such Management Investor, as applicable, in
a manner materially different than any other Investor; provided that PIC or such Management Investor, as applicable, shall be given prompt written notice of any such amendment or waiver to which PIC or such Management Investor, as applicable, did
not consent. No waivers of or exceptions to any term, condition, or provision of this Agreement, in any one or more instances, shall be deemed to be or construed as a further or continuing waiver of any such term, condition, or provision.

 7.7 Severability. The invalidity or unenforceability of any provision hereof shall in no way affect the validity or
enforceability of any other provision. 
 7.8 Aggregation of Stock. All shares of Registrable Securities held or acquired
by Affiliates shall be aggregated together for the purpose of determining the availability of any rights under this Agreement and such Affiliated persons may apportion such rights as among themselves in any manner they deem appropriate. 

7.9 Additional Investors. Notwithstanding anything to the contrary contained herein, if the Company issues additional shares of
the Company’s Series A Preferred Stock after the date hereof, whether pursuant to the Purchase Agreement or otherwise, any purchaser of such shares of Series A Preferred Stock may become a party to this Agreement by executing and delivering an
additional counterpart signature page to this Agreement, and thereafter shall be deemed an “Investor” for all purposes hereunder. No action or consent by the Investors shall be required for such joinder to this Agreement by such additional
Investor, so long as such additional Investor has agreed in writing to be bound by all of the obligations as an “Investor” hereunder. 
 7.10 Entire Agreement. This Agreement (including Schedule A hereto) constitutes the full and entire understanding and agreement among the parties with respect to the

  

					
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	 	Page 22	  

 
subject matter hereof, and any other written or oral agreement relating to the subject matter hereof existing between the parties, including the Predecessor Agreement, is expressly canceled.

 7.11 Delays or Omissions. No delay or omission to exercise any right, power, or remedy accruing to any party under
this Agreement, upon any breach or default of any other party under this Agreement, shall impair any such right, power, or remedy of such nonbreaching or nondefaulting party, nor shall it be construed to be a waiver of or acquiescence to any such
breach or default, or to any similar breach or default thereafter occurring, nor shall any waiver of any single breach or default be deemed a waiver of any other breach or default theretofore or thereafter occurring. All remedies, whether under this
Agreement or by law or otherwise afforded to any party, shall be cumulative and not alternative. 
 [Remainder of Page
Intentionally Left Blank – Signature Pages Follow] 

  

					
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	 	Page 23	  

 IN WITNESS WHEREOF, the parties have executed this Investors’ Rights Agreement as of
the date first written above. 
  

					
	 COMPANY:

	
	 PROTO LABS, INC.

		
	 By:
	 	 /s/ Bradley A. Cleveland

	 Name:
	 	Bradley A. Cleveland
		
	 Title:
	 	President and Chief Executive Officer

  

			
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	Signature Page

 
			
	INVESTORS:
	
	 NORTH BRIDGE GROWTH EQUITY I, L.P.

	
	 By: North Bridge Growth Management, L.P.,

       its General Partner

	
	 By: NBGE GP, LLC, its General Partner

		
	 By:
	 	 /s/ Douglas Kingsley

	 Name:
	 	Douglas Kingsley
	 Title:
	 	Partner
	
	PROTOMOLD INVESTMENT COMPANY, LLC
		
	 By:
	 	 /s/ Brian K. Smith

	 Name:
	 	Brian K. Smith
	 Title:
	 	Chief Manager
		
	 Signature:
	 	 /s/ Lawrence Lukis

	 Name:
	 	Lawrence Lukis
		
	 Signature:
	 	 /s/ Bradley A. Cleveland

	 Name:
	 	Bradley A. Cleveland
		
	 Signature:
	 	 /s/ Bradley A. Cleveland

	 Name:
	 	Bradley A. Cleveland, as Trustee of the
		 	Bradley A. Cleveland Declaration of Trust
		 	dated October 10, 2008
		
	 Signature:
	 	 /s/ Donald Krantz

	 Name:
	 	Donald Krantz
		
	 Signature:
	 	 /s/ Mark Kubicek

	 Name:
	 	Mark Kubicek

  

					
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	 	Signature Page	  

			
	INVESTORS:
		
	Signature:	 	 /s/ Patricia M. Cleveland

	Name:	 	Patricia M. Cleveland, as Co-Trustee of the KEC 2011 Irrevocable Gift Trust
		
	Signature:	 	 /s/ Anne Brenner

	Name:	 	Cornerstone Private Asset Trust Company, LLC, as Co-Trustee of the KEC 2011 Irrevocable Gift Trust
		
	Signature:	 	 /s/ Patricia M. Cleveland

	Name:	 	Patricia M. Cleveland, as Co-Trustee of the JMC 2011 Irrevocable Gift Trust
		
	Signature:	 	 /s/ Anne Brenner

	Name:	 	Cornerstone Private Asset Trust Company, LLC, as Co-Trustee of the JMC 2011 Irrevocable Gift Trust

  

					
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	 	Signature Page	  

 SCHEDULE A 

INVESTORS 
  

					
	 Name and Address
	  	Number of Shares Held	 
		
	 North Bridge Growth Equity I, L.P.
	  	 	427,985	  
		
	 Protomold Investment Company, LLC
	  	 	227,832	  
		
	 Lawrence Lukis
	  	 	495,310	  
		
	 Bradley A. Cleveland
	  	 	—  	  
		
	 Bradley A. Cleveland, as Trustee of the

Bradley A. Cleveland Declaration of Trust dated October 10, 2008
	  	 	89,013	  
		
	 Donald Krantz
	  	 	—  	  
		
	 Mark Kubicek
	  	 	7,500	  
		
	 Patricia M. Cleveland and Cornerstone Private Asset Trust Company,

LLC, as Co-Trustees of the KEC 2011 Irrevocable Gift Trust

c/o Cornerstone Private Asset Trust Company, LLC
	  	 	10,000	  
		
	 Patricia M. Cleveland and Cornerstone Private Asset Trust Company,

LLC, as Co-Trustees of the JMC 2011 Irrevocable Gift Trust

c/o Cornerstone Private Asset Trust Company, LLC
	  	 	10,000	  

  

			
	 Proto Labs, Inc.: Amended and Restated Investors’ Rights Agreement
	  	Schedule AExecutive Employment Agreement

 Exhibit 10.6 
 PROTO LABS, INC. 
 EXECUTIVE EMPLOYMENT AGREEMENT 

This EXECUTIVE EMPLOYMENT AGREEMENT (the
“Agreement”) is entered into as of the 1st day of June, 2011 (the “Effective Date”) by and between PROTO LABS, INC., a Delaware corporation (the
“Company”), and JOHN R. JUDD (“Executive”), an individual residing in the State of Minnesota. 

RECITALS 
 A. The Company desires to employ Executive, and Executive desires to be employed by the Company, in accordance with the terms and conditions stated in this Agreement. 

B. During employment with the Company Executive will have access to confidential, proprietary and trade secret information of the
Company. It is desirable and in the best interests of the Company to protect confidential, proprietary and trade secret information of the Company, to prevent unfair competition by former executives of the Company following separation of their
employment with the Company and to secure cooperation from former executives with respect to matters related to their employment with the Company. 
 C. Executive understands that Executive’s employment and receipt of the compensation and benefits provided for in this Agreement depends on, among other things, Executive’s willingness to agree
to and abide by the non-disclosure, non-competition, non-solicitation, assignment of inventions and other covenants contained in the Proto Labs, Inc. Employee Non-Disclosure and Inventions Assignment Agreement (the “Non-Disclosure
Agreement”) and the Proto Labs, Inc. Non-Competition Agreement (the “Non-Competition Agreement”) attached together as Exhibit A to this Agreement. Executive and the Company acknowledge that Executive was provided
a copy of this Agreement, the Non-Disclosure Agreement and the Non-Competition Agreement before Executive accepted employment with the Company. 
 NOW, THEREFORE, in consideration of the foregoing and the mutual covenants set forth herein, the Company and Executive, intending to be legally bound,
hereby agree as follows: 
 AGREEMENTS 

1. Employment and Duties. Commencing on June 1, 2011, or such other date mutually agreed by the parties, the Company will
employ Executive, and Executive will accept such employment and perform services for the Company, under the terms and conditions set forth in this Agreement. The Executive shall serve as the Company’s Chief Financial Officer and shall perform
such duties of an executive nature as the Company may assign from time to time. Executive will follow and comply with applicable policies and procedures adopted by the Company from time to time, including without limitation policies relating to
business ethics, conflict of interest, non-discrimination, confidentiality and protection of trade secrets, and insider trading. Executive shall devote his full working time and efforts to the Company’s business, to

 
the exclusion of all other employment or active participation in other material business interests, unless otherwise consented to in writing by the disinterested members of the Board of Directors
of the Company (the “Board”); provided, however, that during the period from June 1, 2011 through June 30, 2011, Executive may provide such reasonable transition assistance to his former employer as agreed
between Executive and his former employer. The Executive may not serve as a director on any board of directors without the unanimous written consent of the Board. Executive hereby represents and confirms that Executive is under no contractual or
legal commitments that would prevent Executive from fulfilling Executive’s duties and responsibilities as set forth in this Agreement. 
 2. At will Employment. Executive’s employment with Company shall be at will and Executive’s employment may be unilaterally terminated by either party subject to the terms of
Section 5 of this Agreement. 
 3. Compensation. While employed by the Company during the term of this Agreement
(the “Term” as defined in Section 14 below), Executive will be provided with the following compensation and benefits: 
 A. Base Salary. The Company will pay to Executive for services provided hereunder an initial base salary at the annualized rate of $240,000, which base salary will be paid in accordance with
the Company’s normal payroll policies and procedures (“Base Salary”). The Company will review Executive’s performance on an annual basis and determine any adjustments to Executive’s Base Salary in its sole
discretion. 
 B. Annual Bonus. Executive will be eligible for an annual target incentive award of 50% of
Executive’s then-current base salary (the “Annual Bonus”), based on achievement of objectives as determined by the Company, payable no later than March 15 of the calendar year following the calendar year for which
the bonus was earned. Any Annual Bonus that may awarded for 2011 will be pro-rated from the date Executive commences employment under this Agreement. 
 C. Employee Benefits. Executive will be entitled to participate in all employee benefit plans and programs generally available to executive employees of the Company, as determined by the
Company and to the extent that Executive meets the eligibility requirements for each individual plan or program. Executive’s participation in any plan or program will be subject to the provisions, rules, and regulations of, or applicable to,
the plan or program. The Company provides no assurance as to the adoption or continuation of any particular employee benefit plan or program. Under the Company’s program currently in effect as of the Effective Date, Executive will initially
accrue paid time off at the annual rate of 160 hours. 
 D. Expenses. The Company will reimburse Executive for all
reasonable and necessary out-of-pocket business, travel, and entertainment expenses incurred by Executive in the performance of his duties and responsibilities to the Company during the Term. Such reimbursement shall be subject to the Company’s
normal policies and procedures for expense verification, documentation, and reimbursement. 

  
 2 

 E. Initial Equity. Executive will be granted a non-statutory stock option
under the Company’s 2000 Stock Option Plan to acquire 12,500 shares of the Company’s common stock at a per share exercise price equal to the fair market value of a share of the Company’s common stock on the date the option is
granted. The option will be granted at the first meeting of the Compensation Committee of the Board occurring on or after the commencement date of Executive’s employment hereunder, provided the Compensation Committee has by that time
received an updated valuation report to be submitted by the third-party valuation firm retained by the Company. The option shall vest and become exercisable as to one-third of the shares subject to the option on June 1 of 2012, 2013 and
2014, and shall otherwise be subject to the terms and conditions contained in the Company’s current form of non-statutory stock option agreement. 
 F. IPO Incentive. In recognition of Executive’s services in support of the Company’s plans for an initial public offering of the Company’s stock (the “IPO”), the
Company will pay Executive a cash bonus in an amount equal to $75,000 on the date that the IPO occurs, but in any case no later than March 15, 2012. 
 4. Non-Disclosure and Non-Competition. At the same time as Executive signs this Agreement, Executive will sign both the Non-Disclosure Agreement and the Non-Competition Agreement in the form
attached as Exhibit A, in consideration of Executive’s employment hereunder and the payments and benefits provided to Executive pursuant to this Agreement and other good and valuable consideration. 

5. Termination. 
 A. Voluntary Termination. Except as provided in Sections 5.B., C., D. and E., each party hereto may terminate Executive’s employment by giving to the other party no less than thirty
(30) days’ prior written notice of the party’s intent to terminate. If Executive voluntarily terminates his employment without Good Reason, then the Company shall have no further liability to Executive for any payment, compensation or
benefit whatsoever, other than payment of Executive’s accrued but unpaid salary and benefits through the date of Executive’s termination. If the Company voluntarily terminates Executive’s employment without Cause (as set forth in
Section 5.D. hereof) or Executive terminates his employment for Good Reason (as set forth in Section 5.E.), and subject to Executive’s compliance with Section 6 of this Agreement and with the Non-Disclosure Agreement and the
Non-Competition Agreement, then Executive shall be entitled to severance payments and benefits as described in Section 6 of this Agreement. 
 B. By Death. Executive’s employment shall be terminated automatically upon the death of Executive. The Company’s total liability in such event shall be limited to payment of
Executive’s accrued but unpaid salary and benefits through the date of Executive’s death. 
 C. By Disability.
The Company may terminate Executive’s employment upon the inability of Executive to perform on a full-time basis the duties and responsibilities of his employment with the Company by reason of his illness or other physical or mental
impairment or condition, if such inability continues for an uninterrupted period of 90 days. A period of inability shall be “uninterrupted” unless and until Executive returns to full-time work

  
 3 

 
for a continuous period of at least 30 days. The Company shall have no liability for severance pay or benefits following the date of Executive’s termination of employment, other than payment
of Executive’s accrued but unpaid salary and benefits through the date of Executive’s termination and any rights Executive has to disability insurance benefits under applicable law or the Company’s short or long term disability
insurance policies as in effect at the time of termination. 
 D. For Cause. The employment relationship between
Executive and the Company created hereunder shall automatically and immediately terminate upon the occurrence of any one of the following events: 
 (i) the conviction of Executive of a felony; 
 (ii) the gross
negligence or willful misconduct of Executive which is reasonably determined by the Board to be injurious to the business or interests of the Company; 
 (iii) Executive’s willful violation of specific and lawful directions of the Board, which persists for a period of 5 days after notice is given of such willful violation; 

(iv) excessive absenteeism of Executive which persists for a period of 30 days after the Board has given the Executive notice of
such absenteeism; 
 (v) material failure of Executive to perform or observe the provisions of this Agreement with the
Company which persists for a period of 30 days after notice is given of such failure to perform or observe; 
 (vi)
failure to cooperate with the Company in any investigation or formal proceeding; or 
 (vii) any act of fraud with
respect to any aspect of the Company’s business where such act is reasonably determined by the Board to be injurious to the business of the Company. 
 E. Good Reason. Executive’s voluntary resignation of his employment under this Agreement will be considered to be with “Good Reason” if, following the occurrence of one or more of
the events listed below, Executive (1) provides written notice to the Board of the event(s) constituting Good Reason within thirty (30) days after the first occurrence of such event(s), (2) the Company fails to reasonably cure such
event(s) within thirty (30) days after receiving such notice, and (3) Executive’s termination of his employment is effective not later than thirty (30) days after the end of the period in which the Board may cure the event(s).
The following events will give rise to Good Reason, unless Executive has consented thereto in writing: 
 (i) A material
reduction or diminution in the Executive’s job responsibilities or duties; provided, however, that neither a mere change in title alone nor reassignment to a position that is substantially similar to the position held prior to the reassignment
shall constitute Good Reason (including but not limited to, following a Change in Control, performing substantially the same duties with respect to substantially the same size and scope of organization, but which organization is part of a larger
organization); 

  
 4 

 (ii) A material reduction by the Company of Executive’s Base Salary as in
effect on the date of this Agreement or as same may be increased from time to time thereafter; provided, however, that a reduction of Base Salary in connection with a similar general reduction of the base salaries of the Company’s executive
employees shall not constitute Good Reason; 
 (iii) The relocation of Executive’s primary work location, on a
permanent basis, to an office that would increase the Executive’s one way commute distance by more than seventy-five (75) miles from Executive’s primary work location as of immediately prior to such change; or 

(iv) any acquirer, successor or assignee of the Company fails to assume and perform, in all material respects, the obligations of
the Company hereunder. 
 6. Severance and Change in Control. 

A. Severance Payments. If during the Term of this Agreement the Company voluntarily terminates Executive’s employment without
Cause (and other than as a result of Executive’s death or disability (as defined above)) or Executive resigns his employment with Good Reason, and if the termination or resignation with Good Reason occurs on or within eighteen (18) months
following a Change in Control (as defined below), such that in either case Executive’s termination of employment constitutes an involuntary “separation from service” under Section 409A of the Internal Revenue Code (together, with
any state law of similar effect, “Section 409A”), and provided that Executive signs and does not rescind a general waiver and release of claims in favor of the Company and its affiliates in a form to be prescribed by the
Company (the “Release”), and provided further that Executive is in compliance with his continuing obligations to the Company (including but not limited to those in the Non-Disclosure Agreement and the Non-Competition
Agreement), then: 
 (i) Cash Severance. Executive shall be entitled to receive a lump sum payment equal to one times
Executive’s Base Salary as in effect immediately prior to the Change in Control, less applicable withholding, plus one times Executive’s target Annual Bonus for the year in which the Change in Control occurs, less applicable withholdings
(the “Cash Severance”); and 
 (ii) Benefits Continuation. If Executive was enrolled in a group
health plan (e.g., medical, dental, or vision plan) sponsored by the Company immediately prior to termination, and if Executive (or his eligible dependents) timely elects to continue such coverage under the Consolidated Omnibus Budget
Reconciliation Act of 1985 (together with any state law of similar effect, “COBRA”) the Company will pay to the insurance carrier(s) its share of the premiums due for Executive and his eligible dependents for the first twelve
(12) months of such coverage under COBRA (or until such earlier time as Executive and/or his eligible dependents are no longer eligible for COBRA coverage) (the “Benefits Continuation” and together with the Cash
Severance, the “Payments”). 

  
 5 

 B. Release; Timing of Cash Severance. Executive must execute the Release within
forty-five (45) days following the date of termination, and allow the Release to become effective in accordance with its terms. If the Release becomes effective within such time period, and subject to Executive’s observation of his
continuing obligations, the Company will pay the Cash Severance on the first regular payroll pay date to occur at least 65 days after the date of termination, but in any case no later than the date that is two and a half months after the end of the
year in which the date of termination occurred. 
 C. Stock Options. Notwithstanding any other provision in this
Agreement to the contrary, any stock options granted to Executive by the Company shall be subject the terms of the applicable award agreements and the Company’s 2000 Stock Option Plan with respect to any termination of Executive’s
employment or any “Change in Control” (as defined in the Company’s 2000 Stock Option Plan) of the Company. 

D. Conditional Six-Month Delay. The Payments are intended to be exempt from the requirements for deferred compensation under
Section 409A and should be interpreted and administered accordingly. However, if the Company (or, if applicable, the successor entity thereto) determines that the Payments constitute “deferred compensation” under Section 409A and
Executive is a “specified employee” of the Company or any successor entity thereto, as such term is defined in Section 409A(a)(2)(B)(i) (a “Specified Employee”), then, solely to the extent necessary to avoid
the incurrence of the adverse personal tax consequences under Section 409A, the timing of the Payments shall be delayed as follows: on the earliest to occur of (i) the date that is six months and one day after the termination date,
(ii) the date of the Specified Employee’s death, or (iii) such earlier date, as reasonably determined in good faith by the Company (or any successor entity thereto), as would not result in any of the Payments being subject to adverse
personal tax consequences under Section 409A (such earliest date, the “Delayed Initial Payment Date”), the Company (or the successor entity thereto, as applicable) shall (A) pay to Executive a lump sum amount equal
to the sum of the Payments that Executive would otherwise have received through the Delayed Initial Payment Date if the commencement of the payment of the Payments had not been delayed pursuant to this Section 6(D) and (B) commence paying
the balance of the Payments in accordance with the applicable payment schedules set forth in Section 6(A) above. For the avoidance of doubt, it is intended that (1) each installment of the Payments provided in Section 6(A) above is a
separate “payment” for purposes of Section 409A, (2) all Payments satisfy, to the greatest extent possible, the exemptions from the application of Section 409A provided under of Treasury Regulation 1.409A-1(b)(4)-(6), and
1.409A-1(b)(9)(iii), and (3) the Payments consisting of COBRA premiums also satisfy, to the greatest extent possible, the exemptions from the application of Section 409A provided under Treasury Regulation 1.409A-1(b)(9)(v). 

E. Golden Parachute Tax. 
 (i) If any payment or benefit (including payments and benefits pursuant to this Agreement and the acceleration of the vesting and exercisability of a stock option award) in the nature of
compensation that Executive would receive in connection with a change in the ownership or effective control of the Company or in the ownership of a substantial portion of the assets of the Company (collectively, a “Transaction
Payment”) would constitute a “parachute payment” within the meaning of Section 280G of the Internal Revenue Code of 1986, 

  
 6 

 
as amended (the “Code”), then such Transaction Payment shall be reduced to the largest amount as, in the sole judgment of the Compensation Committee of the Board, will
result in no portion of such Transaction Payment being subject to the excise tax imposed by Section 4999 of the Code (a “Reduced Payment”). If a Reduced Payment is to be made, any reduction in the Transaction Payment
shall occur in the following order: (1) reduction of cash payments other than under this Agreement (if any); (2) cancellation or reduction of accelerated vesting of stock options; and (3) reduction of other payments or benefits (if
any) paid to Executive. In the event that acceleration of vesting of Executive’s stock options is to be reduced, such acceleration of vesting shall be canceled in the reverse order of the date of grant. 

(ii) The independent registered public accounting firm engaged by the Company for general audit purposes as of the day prior to
the effective date of the Change in Control may be utilized by the Compensation Committee to make all determinations required to be made under this Section 6(E). If the independent registered public accounting firm so engaged by the Company is
serving as accountant or auditor for the individual, entity or group effecting the Change in Control, the Compensation Committee may appoint a nationally recognized independent registered public accounting firm to make the determinations required
hereunder. The Company shall bear all expenses with respect to the determinations by any such independent registered public accounting firm retained hereunder. 
 (iii) Any independent registered public accounting firm engaged to make the determinations hereunder shall provide its calculations, together with detailed supporting documentation, to the Company
and Executive within fifteen (15) calendar days after the date on which Executive’s right to a Transaction Payment is triggered (if requested at that time by the Compensation Committee) or such other time as reasonably requested by the
Compensation Committee. Any good faith determinations of the accounting firm made hereunder shall be final, binding and conclusive upon the Company and Executive. 
 F. Change in Control. For purposes of this Section 6, “Change in Control” means the occurrence, in a single transaction or in a series of related transactions, of any
one or more of the following events: 
 (i) any “Person” (as such term is used in Sections 13(d) and 14(d) of
the Securities Exchange Act of 1934, as amended) becomes the beneficial owner (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing more than fifty percent (50%) of the combined
voting power of the Company’s then outstanding securities other than by virtue of a merger, consolidation or similar transaction. Notwithstanding the foregoing, a Change in Control shall not be deemed to occur (a) on account of the
acquisition of beneficial ownership of securities of the Company by any Person from the Company in a transaction or series of related transactions the primary purpose of which is to obtain financing for the Company through the issuance of equity
securities; (b) on account of the beneficial ownership of securities of the Company by the Company, any of its subsidiaries, or any employee benefit plan or related trust sponsored or maintained by the Company or any of its subsidiaries; or
(c) solely because the level of ownership held by any Person (the “Subject Person”) exceeds the designated percentage threshold of the outstanding voting securities as a result of a repurchase or other acquisition of
voting securities by the Company reducing the number of shares outstanding, provided that if a Change in Control would occur (but for the 

  
 7 

 
operation of this sentence) as a result of the acquisition of voting securities by the Company, and after such share acquisition, the Subject Person becomes the owner of any additional voting
securities that, assuming the repurchase or other acquisition had not occurred, increases the percentage of the then outstanding voting securities owned by the Subject Person over the designated percentage threshold, then a Change in Control shall
be deemed to occur; 
 (ii) there is consummated a merger, consolidation or similar transaction involving (directly or
indirectly) the Company and, immediately after the consummation of such merger, consolidation or similar transaction, the stockholders of the Company immediately prior thereto do not own, directly or indirectly, either (a) outstanding voting
securities representing more than fifty percent (50%) of the combined outstanding voting power of the surviving entity in such merger, consolidation or similar transaction or (b) more than fifty percent (50%) of the combined
outstanding voting power of the parent of the surviving entity in such merger, consolidation or similar transaction, in each case in substantially the same proportions as their ownership of the outstanding voting securities of the Company
immediately prior to such transaction; 
 (iii) there is consummated a sale, lease, exclusive license or other
disposition of all or substantially all of the consolidated assets of the Company and its subsidiaries, other than a sale, lease, license or other disposition of all or substantially all of the consolidated assets of the Company and its subsidiaries
to an entity, more than fifty percent (50%) of the combined voting power of the voting securities of which are owned by stockholders of the Company in substantially the same proportions as their ownership of the outstanding voting securities of
the Company immediately prior to such sale, lease, license or other disposition; or 
 (iv) over a twelve month period,
individuals who, on the Effective Date, are members of the Board (the “Incumbent Board”) cease for any reason to constitute at least a majority of the members of the Board; provided, however, that if the appointment or
election (or nomination for election) of any new Board member was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for purposes of the Plan, be considered as a member of
the Incumbent Board. 
 For avoidance of doubt, the term Change in Control shall not include a sale of assets, merger or other
transaction effected exclusively for the purpose of changing the domicile of the Company. 
 7. Remedies. Each of the
parties to this Agreement will be entitled to enforce its rights under this Agreement specifically, to recover damages by reason of any breach of any provision of this Agreement and to exercise all other rights existing in its favor. The parties
hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction in
accordance with Section 13 for injunctive relief in order to enforce or prevent any violations of the provisions of this Agreement. 
 8. Attorney Fees. If any arbitration proceeding or action at law or in equity, including any action for declaratory or injunctive relief, is brought which arises out of this

  
 8 

 
Agreement or the termination of Executive’s employment, or which seeks to enforce or interpret this Agreement or to seek damages for its breach, the prevailing party shall be entitled to
recover reasonable attorney fees from the non-prevailing party, which fees may be set by the court or arbitrator in the trial of such action, or may be enforced in a separate action brought for that purpose, and which fees shall be in addition to
any other relief which may be awarded. 
 9. Assignment. This Agreement is personal to Executive and may not be assigned
in any way by Executive without the prior written consent of the Company. This Agreement shall not be assignable or delegable by the Company. Any attempted assignment by Executive or the Company shall be void. Notwithstanding the preceding two
sentences, this Agreement may be assigned or delegated by the Company to any parent company, subsidiary, successor or affiliate (where such affiliate is at least 51% owned by the Company) of the Company. The rights and, obligations under this
Agreement shall inure to the benefit of and shall be binding upon the heirs, legatees, administrators and personal representatives of Executive and upon the successors, affiliates, representatives and assigns of the Company. 

10. Severability and Reformation. The parties hereto intend all provisions of this Agreement to be enforced to the fullest extent
permitted by law, and are intended to be limited to the extent necessary so that they will not render this Agreement illegal, invalid, or unenforceable under present or future law. If any provision of this Agreement or any application thereof shall
be held to be invalid, illegal or unenforceable, the validity, legality and enforceability of such provision shall be fully severable, and this Agreement shall be construed and enforced as if such illegal, invalid, or unenforceable provision were
never a part hereof and the remaining provisions shall remain in full force and effect and shall not be affected by the illegal, invalid, or unenforceable provision or by its severance. 

11. Notices. All notices and other communications required or permitted to be given hereunder shall be in writing and shall be
deemed to have been duly given if delivered personally, mailed by certified mail (return receipt requested) or sent by overnight delivery service, cable, telegram, facsimile transmission or telex to the parties at the following addresses or at such
other addresses as shall be specified by the parties by like notice: 
 If to the Company: 

Proto Labs, Inc. 
 5540 Pioneer Creek Drive

 Maple Plain, MN 55359 
 Attention:
President and CEO 
 If to the Executive: 
 John R. Judd 
 5540 Pioneer Creek Drive 
 Maple Plain, MN 55359 
 Notice so given shall, in the case of notice so given by mail, be deemed
to be given and received on the fourth calendar day after posting, in the case of notice so given by overnight delivery service, on the date of actual delivery and, in the case of notice so given by cable, telegram, facsimile transmission, telex or
personal delivery, on the date of actual transmission or, as the case may be, personal delivery. 

  
 9 

 12. Further Actions. Whether or not specifically required under the terms of this
Agreement, each party hereto shall execute and deliver such documents and take such further actions as shall be necessary in order for such party to perform all of his or its obligations specified herein or reasonably implied from the terms hereof.

 13. Governing Law and Venue. This Agreement is to be governed by and construed in accordance with the laws of the
State of Minnesota without giving effect to any choice or conflict of law provision or rule that would cause the application of laws of any jurisdiction other than the state of Minnesota. The parties agree that any dispute concerning this Agreement
is to be brought in the District Court in Hennepin County, Minnesota and consent to jurisdiction and venue therein. 
 14.
Term. The term of this Agreement (the “Term”) shall be the period commencing on the Effective Date and ending on the first anniversary of the Effective Date, provided that such period shall be automatically extended for
successive one-year periods unless either party gives written notice of non-renewal to the other party at least ninety (90) days prior to the expiration of such first anniversary, or annual renewal, as the case may be; provided, further, that
if a Change in Control occurs prior to the expiration of the Term specified in the preceding clause (including any extension year then in effect), then the Term shall end upon expiration of the eighteen-month period commencing on the date that the
Change in Control occurs. 
 15. Entire Agreement. This Agreement, the Non-Disclosure Agreement and the Non-Competition
Agreement contain the entire understanding and agreement between the parties, except as otherwise specified herein, and supersede any other agreement between Executive and the Company, whether oral or in writing, with respect to the same subject
matter, including without limitation the offer letter to Executive from the Company dated May 4, 2011 and the Employee Agreement attached thereto (together, the “Offer Letter”); provided, however, that nothing
herein shall supersede or replace the Company’s 2000 Stock Option Plan and any award agreement with the Executive entered into thereunder. 
 16. No Waiver. No term or condition of this Agreement shall be deemed to have been waived, except by a statement in writing signed by the party against whom enforcement of the waiver is sought. Any
written waiver shall not be deemed a continuing waiver unless specifically stated, shall operate only as to the specific term or condition waived, and shall not constitute a waiver of such term or condition for the future or as to any act other than
that specifically waived. 
 17. Counterparts. This Agreement may be executed in counterparts, with the same effect as if
both parties had signed the same document. All such counterparts shall be deemed an original, shall be construed together and shall constitute one and the same instrument. 
 18. Section 409A. This Agreement and the payments hereunder are intended to be exempt from or to satisfy the requirements of Section 409A(a)(2), (3) and (4) of the Internal
Revenue Code of 1986, as amended (the “Code”), including current and future guidance and regulations interpreting such provisions, and should be interpreted and administered accordingly. 

  
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 IN WITNESS WHEREOF, the
parties have executed this Agreement as of the date first above written. 
  

			
	THE COMPANY:
	
	 PROTO LABS, INC.

		
	 By
	 	 /s/ Bradley A. Cleveland

		 	Bradley A. Cleveland
		 	Chief Executive Officer
	
	EXECUTIVE:
	
	 /s/ John R. Judd

	John R. Judd

  
 11

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