UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549





FORM 20-F/A

(Amendment No. 1)







|☐ | REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------------

OR



|☒ | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ------------------------------------------------------------------------------------

For the fiscal year ended December 31, 2018

OR



|☐ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------

OR



|☐ | SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | -------------------------------------------------------------------------------------------

Commission File Number: 001-36515





MATERIALISE NV

(Exact
name of Registrant as specified in its charter)





Not
Applicable

(Translation of Registrants name into English)

Kingdom of Belgium

(Jurisdiction of incorporation or organization)

Technologielaan 15, 3001 Leuven, Belgium

(Address of principal executive offices)





Peter Leys,
telephone +32 (16) 39 66 11, facsimile +32 (16) 39 66 00, Technologielaan 15, 3001 Leuven, Belgium

(Name, Telephone, E-mail
and/or Facsimile number and Address of Company Contact Person)

Securities registered or to be registered pursuant to
Section 12(b) of the Act:



|                                                                                             |  |                   |  |                                          
|-------------------------------------------------------------------------------------------- |  | ----------------- |  | -----------------------------------------
|Title of each class                                                                          |  | Trading Symbol(s) |  | Name of each exchange on which
registered
|American Depositary Shares, each representing one
Ordinary Share, no nominal value per share |  | MTLS              |  | The NASDAQ Stock Market LLC              
|Ordinary Shares, no nominal value per share*                                                 |  |                   |  | The NASDAQ Stock Market LLC              



|* | Not for trading but only in connection with the registration of the American Depositary Shares pursuant to the
requirements of the Securities and Exchange Commission.
|- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------

Securities registered or to be registered pursuant to
Section 12(g) of the Act: None.

Securities for which there is a reporting obligation pursuant to Section 15(d) of the
Act: None.





The number of outstanding shares of each of the issuers classes of capital or common stock as of December 31, 2018 was: 52,890,761 Ordinary Shares

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities
Act.    ☐  Yes    ☒  No

If this report is an annual or transition report,
indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.    ☐  Yes    ☒  No

Note  Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange
Act of 1934 from their obligations under those Sections.

Indicate by check mark whether the registrant (1) has filed all reports required to be
filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for
the past 90 days.    ☒  Yes     ☐  No

Indicate by check mark whether the
registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was
required to submit and post such files).    ☒  Yes     ☐  No

Indicate by check
mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or an emerging growth company. See the definitions of large accelerated filer, accelerated filer, and emerging
growth company in Rule 12b-2 of the Exchange Act.



|                        |  |   |  |                         |  |  
|----------------------- |  | - |  | ----------------------- |  | -
|Large accelerated filer |  | ☐ |  | Accelerated filer       |  | ☒
|                        |  |   | 
|Non-accelerated filer   |  | ☐ |  | Emerging growth company |  | ☒

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if
the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.    ☐



| | The term new or revised financial accounting standard refers to any update issued by the Financial
Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.
|- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Indicate by check mark which basis of
accounting the registrant has used to prepare the financial statements included in this filing:



|             |  |                                                                                                          |  |         
|------------ |  | -------------------------------------------------------------------------------------------------------- |  | --------
|U.S. GAAP  ☐ |  | International Financial Reporting Standards as issued by the International Accounting Standards Board  ☒ |  | Other  ☐

If Other has been checked in response to the previous question, indicate by check mark which financial statement
item the registrant has elected to follow.    ☐ Item 17    ☐ Item 18

If this is an annual
report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act.).    ☐  Yes     ☒  No

(APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PAST FIVE YEARS)

Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Sections 12, 13 or 15(d) of the Securities Exchange
Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court.     ☐ Yes     ☐ No









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EXPLANATORY NOTE

This Amendment No. 1 on Form 20-F/A (this Amendment) amends the Annual Report on Form 20-F for the year ended
December 31, 2018 of Materialise NV (the Company), as originally filed with the U.S. Securities and Exchange Commission on April 30, 2019 (the Original Form 20-F). The Company is filing this Amendment solely to
include the financial statements and related notes of RSPRINT Powered by Materialise NV (RSPRINT) as required by Rule 3-09 of Regulation S-X under the Securities Exchange Act of 1934, as amended (Rule 3-09).

The Company owns a 50% non-controlling interest in RSPRINT and accounts for RSPRINT using the equity method of accounting. RSPRINT met
the significance test of an equity investee as of and for the years ended December 31, 2017 and 2016.

The Form 20-F is being
further amended to include as exhibits: (i) unaudited financial statements of RSPRINT as of and for the year ended December 31, 2018 and audited financial statements of RSPRINT as of and for the years ended December 31, 2017 and 2016,
prepared in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board; (ii) the consent of BDO Bedrijfsrevisoren CVBA, the independent auditor of RSPRINT; (iii) certifications by
the Companys Chief Executive Officer and Chief Financial Officer and (iv) the Description of Securities required pursuant to amendments to Form 20-F that became effective subsequent to the filing of the Original Form 20-F.

Other than as required to reflect the amendments discussed above, this Amendment does not, and does not purport to, amend, update or restate
any other information in the Original Form 20-F, or reflect any events that have occurred after the filing of the Original Form 20-F.



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PART III



|ITEM 19. | EXHIBITS
|-------- | --------



|      |  |                                                                                                                                                                                                                                                                                                                                                                   
|----- |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|      | 
|1.1*  |  | Restated Articles of Association of Materialise NV (English translation)                                                                                                                                                                                                                                                                                          
|      | 
|2.1   |  | Deposit Agreement, dated as of June 
24, 2014, among Materialise NV and The Bank of New York Mellon (incorporated by reference to Exhibit 4.1 to the Companys Registration Statement on Form F-1 (File No. 
333-194982))                                                                                                                                         
|      | 
|2.2   |  | Form of American Depositary Receipt (included in Exhibit 2.1)                                                                                                                                                                                                                                                                                                     
|      | 
|2.3   |  | Description of Securities                                                                                                                                                                                                                                                                                                                                         
|      | 
|      |  | Certain instruments relating to long-term debt as to which the total amount of securities authorized thereunder does not exceed 10% of the total assets of Materialise NV and its subsidiaries on a consolidated basis have been omitted
in accordance with Form 20-F. The Company hereby agrees to furnish a copy of any such instrument to the SEC upon request.
|      | 
|4.1   |  | 2013 Warrant Plan (English translation) (incorporated by reference to Exhibit 10.2 to the Companys Registration Statement on Form F-1 (No. 333-194982))                                                                                                                                                                                                          
|      | 
|4.2   |  | 2014 Warrant Plan (English translation) (incorporated by reference to Exhibit 10.3 to the Companys Registration Statement on Form F-1 (No. 333-194982))                                                                                                                                                                                                          
|      | 
|4.3   |  | Form of Warrant Agreement under 2014 Warrant Plan (English translation) (incorporated by reference to Exhibit 4.6 to the Companys Registration
 Statement on Form S-8 (No. 333-197236))                                                                                                                                                                          
|      | 
|4.4   |  | 2015 Warrant Plan (English translation) (incorporated by reference to Exhibit 4.5 to the Companys Annual Report on Form 20-F for the year ended December 31, 2015)                                                                                                                                                                                               
|      | 
|4.5   |  | Form of Warrant Agreement under 2015 Warrant Plan (English translation) (incorporated by reference to Exhibit 4.4 to the Companys Registration
 Statement on Form S-8 (File No. 333-212445))                                                                                                                                                                     
|      | 
|4.6   |  | Registration Rights Agreement, dated September 
15, 2016, among Materialise NV and the Holders party thereto (incorporated by reference to Exhibit 4.8 to the Companys Registration Statement on Form F-3 (No. 333-213649))                                                                                                                                      
|      | 
|4.7+  |  | Share and Loan Purchase and Transfer Agreement, dated October 
4, 2017, among Materialise GmbH, Materialise N.V. and the Sellers party thereto (incorporated by reference to Exhibit 4.9 to the Companys Annual Report on Form 20-F for the year ended December 
31, 2017)                                                                                       
|      | 
|8.1*  |  | Subsidiaries of Materialise NV                                                                                                                                                                                                                                                                                                                                    
|      | 
|12.1* |  | Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                                                                
|      | 
|12.2* |  | Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                                                                
|      | 
|12.3  |  | Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                                                                
|      | 
|12.4  |  | Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                                                                
|      | 
|13.1* |  | Certification of Chief Executive Officer Pursuant to 18 U.S.C. Section 1350, as adopted Pursuant to Section 
906 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                
|      | 
|13.2* |  | Certification of Chief Financial Officer Pursuant to 18 U.S.C. Section 1350, as adopted Pursuant to Section 
906 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                
|      | 
|13.3  |  | Certification of Chief Executive Officer Pursuant to 18 U.S.C. Section 1350, as adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                 
|      | 
|13.4  |  | Certification of Chief Financial Officer Pursuant to 18 U.S.C. Section 1350, as adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                                                                                                                                                                                                                 
|      | 
|23.1* |  | Consent of BDO Bedrijfsrevisoren CVBA, independent registered public accounting firm                                                                                                                                                                                                                                                                              
|      | 
|23.2  |  | Consent of BDO Bedrijfsrevisoren CVBA, independent accountants                                                                                                                                                                                                                                                                                                    
|      | 
|99.1  |  | Financial Statements of RSPRINT Powered by Materialise NV, as of and for the years ended December 31, 2018, 2017 and 2016                                                                                                                                                                                                                                         



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|         |  |                                              
|-------- |  | ---------------------------------------------
|         | 
|101.INS* |  | XBRL Instance Document                       
|         | 
|101.SCH* |  | XBRL Taxonomy Extension Schema               
|         | 
|101.CAL* |  | XBRL Taxonomy Extension Calculation Linkbase 
|         | 
|101.DEF* |  | XBRL Taxonomy Extension Definition Linkbase  
|         | 
|101.LAB* |  | XBRL Taxonomy Extension Label Linkbase       
|         | 
|101.PRE* |  | XBRL Taxonomy Extension Presentation Linkbase



|* | Previously filed with the Original Form 20-F.
|- | ---------------------------------------------

|+ | The registrant has omitted portions of the referenced exhibit pursuant to a request for confidential treatment
under Rule 24b-2 promulgated under the Exchange Act.
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------



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Signatures

The registrant hereby certifies that it meets all of the requirements for filing on Form 20-F and that it has duly caused and authorized the
undersigned to sign this Amendment No.1 to the annual report on its behalf.



|               |  |                        
|-------------- |  | -----------------------
|MATERIALISE NV
|               | 
|By:            |  | /s/ Wilfried Vancraen  
|Name:          |  | Wilfried Vancraen      
|Title:         |  | Chief Executive Officer

Date: June 28, 2019