UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934
For the month of May 2017
Commission File Number: 001-36515

Materialise NV

Technologielaan 15
3001 Leuven
Belgium
(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.
Form 20-F  ☒             Form 40-F  ☐
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐
This Form 6-K is incorporated by reference into the registrant’s Registration Statement on Form F-3 (File No. 333-213649).

First Quarter 2017 Financial Results
Except as otherwise required by the context, references to “Materialise,” “Company,” “we,” “us” and “our” are to Materialise NV and its subsidiaries.
First Quarter 2017 Results
Total revenue for the first quarter of 2017 increased 19.7% to 31,921 kEUR compared to 26,667 kEUR for the first quarter of 2016, with gains in all three of our segments, particularly Materialise Manufacturing.
Revenue from our Materialise Software segment, which offers a proprietary software backbone that enables and enhances the functionality of 3D printers and 3D printing operations worldwide, increased 15.4% to 8,575 kEUR for the first quarter of 2017 from 7,431 kEUR for the same quarter last year. Recurrent revenues from annual and renewed licenses and maintenance fees grew 22.3% from the same period in the prior year.
Revenue from our Materialise Medical segment, which offers a unique platform consisting of medical planning and design software, clinical engineering services and patient specific devices, increased 15.4% to 9,932 kEUR for the first quarter of 2017 compared to 8,606 kEUR for the same period in 2016. Compared to the same quarter in 2016, revenues from our medical software grew 16.0%, and revenues from our collaborated medical device business and from direct sales of complex surgery solutions each grew 15.0%.
Revenue from our Materialise Manufacturing segment, which offers an integrated suite of 3D printing and engineering services to industrial and commercial customers, increased 26.4% to 13,407 kEUR for the first quarter of 2017 from 10,606 kEUR for the first quarter of 2016. End part manufacturing revenues increased 35.0% compared to the first quarter of 2016.
Gross profit was 18,477 kEUR, or 57.9 % of total revenue, for the first quarter of 2017 compared to 15,962 kEUR, or 59.9 % of total revenue, for the first quarter of 2016. The decrease in the gross profit margin was primarily a result of increased production of medical devices and implants, involving higher cost of production.
Research and development (“R&D”), sales and marketing (“S&M”) and general and administrative (“G&A”) expenses increased, in the aggregate, 7.4% to 19,579 kEUR for the first quarter of 2017 from 18,237 kEUR for the first quarter of 2016. R&D expenses increased from 4,372 kEUR to 4,592 kEUR while S&M expenses increased from 8,815 kEUR to 9,608 kEUR. G&A expenses increased from 5,050 kEUR to 5,379 kEUR.
Net other operating income decreased by (268) kEUR to 1,018 kEUR compared to 1,286 kEUR for the first quarter of 2016. Net other operating income consists primarily of withholding tax exemptions for qualifying researchers, development grants, partial funding of R&D projects and currency exchange results on purchase and sales transactions.
Operating loss improved to (84) kEUR from (989) kEUR for the same period in the prior year. This improvement was the result of a combination of an increase in gross profit of 15.8% and an increase of only 7.4% in R&D, S&M and G&A expenses, which were partially offset by a slight decrease of (268) kEUR of net other operating income compared to the same quarter in 2016.

Net financial result was (142) kEUR compared to (734) kEUR for the prior-year period, reflecting smaller variances in the currency exchange rates, primarily on the portion of the Company’s IPO proceeds held in U.S. dollars versus the euro.
Net loss for the first quarter of 2017 was (816) kEUR compared to net loss of (3,151) kEUR for the same period in 2016. The 2016 period contained income tax expense of 1,260 kEUR primarily from deferred taxes compared to income tax expense of 201 kEUR this quarter. The decrease in the net loss for the first quarter of 2017 was primarily attributable to this variance of 1,059 kEUR in income tax, as well as an increase in the financial result of 592 kEUR and the decrease in operating loss by 905 kEUR, which were partially offset by an increase of 221 kEUR in the share in the loss of a joint venture. Total comprehensive loss for the first quarter of 2017, which includes exchange differences on translation of foreign operations, was 694 kEUR compared to 4,115 kEUR for the same period in 2016.
Adjusted EBITDA (a non-IFRS financial measure defined below) increased to 2,813 kEUR from 1,135 kEUR as a result of the combination of continued revenue growth (19.7%) and a significantly lower increase in operational expenses (7.4%) as compared to the first quarter in 2016. The Adjusted EBITDA margin (Adjusted EBITDA divided by total revenue) in the first quarter was 8.8% compared to 4.3% in the first quarter of 2016.
Our Materialise Software segment’s EBITDA rose to 2,993 kEUR from 2,765 kEUR while the segment EBITDA margin (the segment’s EBITDA divided by the segment’s revenue) was 34.9% compared to 37.2% in the prior-year period.
Our Materialise Medical segment’s EBITDA was 314 kEUR compared to (530) kEUR while the segment EBITDA margin increased to 3.2% from (6.2)% in the first quarter of 2016.
Our Materialise Manufacturing segment’s EBITDA rose to 1,322 kEUR from 257 kEUR while the segment EBITDA margin increased to 9.9% from 2.4% for the same quarter in 2016.
At March 31, 2017, we had cash and equivalents of 55,071 kEUR compared to 55,912 kEUR at December 31, 2016. Cash flow from operating activities in the first quarter of 2017 was 1,603 kEUR compared to 1,376 kEUR in the same period in 2016.
Net shareholders’ equity at March 31, 2017 was 78,585 kEUR compared to 79,033 kEUR at December 31, 2016.
Non-IFRS Measures
Materialise uses EBITDA and Adjusted EBITDA as supplemental financial measures of its financial performance. EBITDA is calculated as net profit plus income taxes, financial expenses (less financial income), shares of loss in a joint venture and depreciation and amortization. Adjusted EBITDA is determined by adding non-cash stock-based compensation expenses to EBITDA. Management believes these non-IFRS measures to be important measures as they exclude the effects of items that primarily reflect the impact of long-term investment and financing decisions, rather than the performance of the Company’s day-to-day operations. As compared to net profit, these measures are limited in that they do not reflect the periodic costs of certain capitalized tangible and intangible assets used in generating

revenues in the Company’s business, or the charges associated with impairments. Management evaluates such items through other financial measures such as capital expenditures and cash flow provided by operating activities. The Company believes that these measurements are useful to measure a company’s ability to grow or as a valuation measurement. The Company’s calculation of EBITDA and Adjusted EBITDA may not be comparable to similarly titled measures reported by other companies. EBITDA and Adjusted EBITDA should not be considered as alternatives to net profit or any other performance measure derived in accordance with IFRS. The Company’s presentation of EBITDA and Adjusted EBITDA should not be construed to imply that its future results will be unaffected by unusual or non-recurring items.
Exchange Rate
This document contains translations of certain euro amounts into U.S. dollars at specified rates solely for the convenience of readers. Unless otherwise noted, all translations from euros to U.S. dollars in this document were made at a rate of EUR 1.00 to USD 1.0691, the reference rate of the European Central Bank on March 31, 2017.
About Materialise
Materialise incorporates more than 25 years of 3D printing experience into a range of software solutions and 3D printing services, through which Materialise seeks to form the backbone of the 3D printing industry. Materialise’s open and flexible solutions enable players in a wide variety of industries, including healthcare, automotive, aerospace, art and design, and consumer goods, to build innovative 3D printing applications that aim to make the world a better and healthier place. Headquartered in Belgium, with branches worldwide, Materialise combines one of the largest groups of software developers in the industry with one of the largest 3D printing facilities in the world. For additional information, please visit:  www.materialise.com .

Consolidated income statement (Unaudited)

 	  	For the three months ended 31 March	 	
(in thousands, except per share amounts)	  	2017	 	  	2017	 	  	2016	 	
 	  	U.S.$	 	  	€	 	  	€	 	
 	 	 	 	
Revenue	  	 	34,127	 	  	 	31,921	 	  	 	26,667	 	
Cost of sales	  	 	(14,373)	 	  	 	(13,444)	 	  	 	(10,705)	 	
Gross profit	  	 	19,754	 	  	 	18,477	 	  	 	15,962	 	
Gross profit as % of revenue	  	 	58%	 	  	 	58%	 	  	 	60%	 	
 	  	 	 	 	  	 	 	 	  	 	 	 	
Research and development expenses	  	 	(4,909)	 	  	 	(4,592)	 	  	 	(4,372)	 	
Sales and marketing expenses	  	 	(10,272)	 	  	 	(9,608)	 	  	 	(8,815)	 	
General and administrative expenses	  	 	(5,751)	 	  	 	(5,379)	 	  	 	(5,050)	 	
Net other operating income (expenses)	  	 	1,088	 	  	 	1,018	 	  	 	1,286	 	
Operating (loss) profit	  	 	(90)	 	  	 	(84)	 	  	 	(989)	 	
 	  	 	 	 	  	 	 	 	  	 	 	 	
Financial expenses	  	 	(983)	 	  	 	(919)	 	  	 	(897)	 	
Financial income	  	 	831	 	  	 	777	 	  	 	163	 	
Share in loss of joint venture	  	 	(416)	 	  	 	(389)	 	  	 	(168)	 	
(Loss) profit before taxes	  	 	(658)	 	  	 	(615)	 	  	 	(1,891)	 	
 	  	 	 	 	  	 	 	 	  	 	 	 	
Income taxes	  	 	(215)	 	  	 	(201)	 	  	 	(1,260)	 	
Net (loss) profit of the period	  	 	(873)	 	  	 	(816)	 	  	 	(3,151)	 	
Net (loss) profit attributable to:	  	 	 	 	  	 	 	 	  	 	 	 	
The owners of the parent	  	 	(873)	 	  	 	(816)	 	  	 	(3,151)	 	
Non-controlling interest	  	 	–	 	  	 	–	 	  	 	–	 	
 	  	 	 	 	  	 	 	 	  	 	 	 	
Earnings per share attributable to ordinary owners of the parent	  	 	 	 	  	 	 	 	  	 	 	 	
Basic	  	 	(0.02)	 	  	 	(0.02)	 	  	 	(0.07)	 	
Diluted	  	 	(0.02)	 	  	 	(0.02)	 	  	 	(0.07)	 	
 	  	 	 	 	  	 	 	 	  	 	 	 	
Weighted average basic shares outstanding	  	 	47,325	 	  	 	47,325	 	  	 	47,325	 	
Weighted average diluted shares outstanding	  	 	47,325	 	  	 	47,325	 	  	 	47,325	 	

Consolidated statements of comprehensive income (Unaudited)

 	  	For the three months ended 31 March	 	
(in thousands)	  	2017	 	  	2017	 	  	2016	 	
 	  	U.S.$	 	  	€	 	  	€	 	
 	 	 	 	
Net profit (loss) for the period	  	 	(873)	 	  	 	(816)	 	  	 	(3,151)	 	
Other comprehensive income	  	 	 	 	  	 	 	 	  	 	 	 	
Exchange difference on translation of foreign operations	  	 	130	 	  	 	122	 	  	 	(964)	 	
Other comprehensive income (loss), net of taxes	  	 	130	 	  	 	122	 	  	 	(964)	 	
Total comprehensive income (loss) for the period, net of taxes	  	 	(743)	 	  	 	(694)	 	  	 	(4,115)	 	
Total comprehensive income (loss) attributable to:	  	 	 	 	  	 	 	 	  	 	 	 	
The owners of the parent	  	 	(743)	 	  	 	(694)	 	  	 	(4,115)	 	
Non-controlling interest	  	 	–	 	  	 	–	 	  	 	–	 	

Consolidated statement of financial position (Unaudited)

 	  	As of March 31	 	  	As of
December 31	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
Assets	  	 	 	 	  	 	 	 	
 	 	 	
Non-current assets	  	 	 	 	  	 	 	 	
Goodwill	  	 	8,897	 	  	 	8,860	 	
Intangible assets	  	 	9,468	 	  	 	9,765	 	
Property, plant & equipment	  	 	52,238	 	  	 	45,063	 	
Investments in joint ventures	  	 	111	 	  	 	–	 	
Deferred tax assets	  	 	276	 	  	 	336	 	
Other non-current assets	  	 	2,309	 	  	 	2,154	 	
 	 	 	
Total non-current assets	  	 	73,299	 	  	 	66,178	 	
 	 	 	
Current assets	  	 	 	 	  	 	 	 	
Inventories	  	 	8,267	 	  	 	7,870	 	
Trade receivables	  	 	30,507	 	  	 	27,479	 	
Held to maturity investments	  	 	–	 	  	 	–	 	
Other current assets	  	 	4,691	 	  	 	4,481	 	
Cash and cash equivalents	  	 	55,071	 	  	 	55,912	 	
 	 	 	
Total current assets	  	 	98,536	 	  	 	95,742	 	
Total assets	  	 	171,835	 	  	 	161,920	 	

 	 	 	 	 	 	 	 	 	
 	  	As of March 31	 	  	As of
December 31	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
Equity and liabilities	  	 	 	 	  	 	 	 	
Equity	  	 	 	 	  	 	 	 	
Share capital	  	 	2,729	 	  	 	2,729	 	
Share premium	  	 	79,263	 	  	 	79,019	 	
Consolidated reserves	  	 	(2,417)	 	  	 	(1,603)	 	
 	 	 	
Other comprehensive income	  	 	(990)	 	  	 	(1,112)	 	
 	 	 	
Equity attributable to the owners of the parent	  	 	78,585	 	  	 	79,033	 	
 	 	 	
Non-controlling interest	  	 	–	 	  	 	–	 	
 	 	 	
Total equity	  	 	78,585	 	  	 	79,033	 	
 	 	 	
Non-current liabilities	  	 	 	 	  	 	 	 	
Loans & borrowings	  	 	34,982	 	  	 	28,267	 	
Deferred tax liabilities	  	 	1,256	 	  	 	1,325	 	
Deferred income	  	 	3,942	 	  	 	3,588	 	
 	 	 	
Other non-current liabilities	  	 	2,026	 	  	 	1,873	 	
 	 	 	
Total non-current liabilities	  	 	42,206	 	  	 	35,053	 	
 	 	 	
Current liabilities	  	 	 	 	  	 	 	 	
Loans & borrowings	  	 	6,426	 	  	 	5,539	 	
Trade payables	  	 	13,743	 	  	 	13,400	 	
Tax payables	  	 	874	 	  	 	926	 	
Deferred income	  	 	19,607	 	  	 	17,822	 	
Other current liabilities	  	 	10,394	 	  	 	10,147	 	
 	 	 	
Total current liabilities	  	 	51,044	 	  	 	47,834	 	
Total equity and liabilities	  	 	171,835	 	  	 	161,920	 	

Consolidated statement of cash flows (Unaudited)

 	  	For the three months
ended March 31	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
Operating activities	  	 	 	 	  	 	 	 	
Net (loss) profit of the period	  	 	(816)	 	  	 	(3,151)	 	
Non-cash and operational adjustments	  	 	 	 	  	 	 	 	
Depreciation of property, plant & equipment	  	 	1,945	 	  	 	1,448	 	
Amortization of intangible assets	  	 	623	 	  	 	462	 	
Share-based payment expense	  	 	329	 	  	 	214	 	
Loss (gain) on disposal of property, plant & equipment	  	 	(2)	 	  	 	–	 	
Movement in provisions	  	 	4	 	  	 	–	 	
Movement reserve for bad debt	  	 	122	 	  	 	42	 	
Financial income	  	 	(136)	 	  	 	(48)	 	
Financial expense	  	 	359	 	  	 	254	 	
Impact of foreign currencies	  	 	(81)	 	  	 	528	 	
Share in loss of a joint venture (equity method)	  	 	389	 	  	 	168	 	
Deferred tax expense (income)	  	 	1	 	  	 	868	 	
Income taxes	  	 	203	 	  	 	358	 	
Other	  	 	(72)	 	  	 	–	 	
Working capital adjustment & income tax paid	  	 	 	 	  	 	 	 	
Increase in trade receivables and other receivables	  	 	(3,452)	 	  	 	(285)	 	
Decrease (increase) in inventories	  	 	(406)	 	  	 	215	 	
Increase in trade payables and other payables	  	 	2,729	 	  	 	421	 	
Income tax paid	  	 	(136)	 	  	 	(118)	 	
Net cash flow from operating activities	  	 	1,603	 	  	 	1,376	 	

 	 	 	 	 	 	 	 	 	
 	  	For the three months
ended March 31	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
Investing activities	  	 	 	 	  	 	 	 	
Purchase of property, plant & equipment	  	 	(7,507)	 	  	 	(1,325)	 	
Purchase of intangible assets	  	 	(327)	 	  	 	(265)	 	
Proceeds from the sale of property, plant & equipment (net)	  	 	70	 	  	 	85	 	
Investments in joint-ventures	  	 	(500)	 	  	 	–	 	
Interest received	  	 	108	 	  	 	3	 	
Net cash flow used in investing activities	  	 	(8,156)	 	  	 	(1,502)	 	
 	 	 	
Financing activities	  	 	 	 	  	 	 	 	
Proceeds from loans & borrowings	  	 	7,710	 	  	 	604	 	
Repayment of loans & borrowings	  	 	(756)	 	  	 	(656)	 	
Repayment of finance leases	  	 	(728)	 	  	 	(419)	 	
Interest paid	  	 	(152)	 	  	 	(141)	 	
Other financial income (expense)	  	 	(166)	 	  	 	(33)	 	
Net cash flow from (used in) financing activities	  	 	5,908	 	  	 	(645)	 	
 	 	 	
Net increase of cash & cash equivalents	  	 	(645)	 	  	 	(771)	 	
Cash & cash equivalents at beginning of the period	  	 	55,912	 	  	 	50,726	 	
Exchange rate differences on cash & cash equivalents	  	 	(196)	 	  	 	(520)	 	
Cash & cash equivalents at end of the period	  	 	55,071	 	  	 	49,435	 	

Reconciliation of Net Profit (Loss) to EBITDA and Adjusted EBITDA (Unaudited)

 	  	For the three months
ended 31 March	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
 	 	 	
Net profit (loss) for the period	  	 	(816)	 	  	 	(3,151)	 	
 	  	 	 	 	  	 	 	 	
Income taxes	  	 	201	 	  	 	1,260	 	
Finance expenses	  	 	919	 	  	 	897	 	
Finance income	  	 	(777)	 	  	 	(163)	 	
Share in loss of joint venture	  	 	389	 	  	 	168	 	
Depreciation and amortization	  	 	2,568	 	  	 	1,910	 	
 	  	 	 	 	  	 	 	 	
EBITDA	  	 	2,484	 	  	 	921	 	
 	  	 	 	 	  	 	 	 	
Non-cash stock-based compensation expense (1)	  	 	329	 	  	 	214	 	
 	  	 	 	 	  	 	 	 	
ADJUSTED EBITDA	  	 	2,813	 	  	 	1,135	 	
(1) Non-cash stock-based compensation expenses represent the cost of equity-settled and cash-settled share-based payments to employees.

Segment P&L (Unaudited)

(in thousands)	  	Materialise
Software	 	  	Materialise
Medical	 	  	Materialise
Manufact-
uring	 	  	Total
segments	 	  	Unallocated	 	  	Consoli-
dated	 	
 	  	€	 	  	€	 	  	€	 	  	€	 	  	€	 	  	€	 	
For the three months ended March 31, 2017	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
Revenues	  	 	8,575	 	  	 	9,932	 	  	 	13,407	 	  	 	31,914	 	  	 	8	 	  	 	31,922	 	
Segment EBITDA	  	 	2,993	 	  	 	314	 	  	 	1,322	 	  	 	4,629	 	  	 	(2,145)	 	  	 	2,484	 	
 	 	 	 	 	 	 	
Segment EBITDA %	  	 	34.9%	 	  	 	3.2%	 	  	 	9.9%	 	  	 	14.5%	 	  	 	 	 	  	 	7.8%	 	
 	 	 	 	 	 	 	
For the three months ended March 31, 2016	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
Revenues	  	 	7,431	 	  	 	8,606	 	  	 	10,606	 	  	 	26,643	 	  	 	24	 	  	 	26,667	 	
Segment EBITDA	  	 	2,765	 	  	 	(530)	 	  	 	257	 	  	 	2,492	 	  	 	(1,571)	 	  	 	921	 	
 	 	 	 	 	 	 	
Segment EBITDA %	  	 	37.2%	 	  	 	-6.2%	 	  	 	2.4%	 	  	 	9.4%	 	  	 	 	 	  	 	3.5%	 	

Reconciliation of Net Profit (Loss) to Segment EBITDA (Unaudited)

 	  	For the three months
ended 31 March	 	
(in thousands)	  	2017	 	  	2016	 	
 	  	€	 	  	€	 	
 	 	 	
Net profit (loss) for the period	  	 	(816)	 	  	 	(3,151)	 	
Income taxes	  	 	201	 	  	 	1,260	 	
Finance cost	  	 	919	 	  	 	897	 	
Finance income	  	 	(777)	 	  	 	(163)	 	
Share in loss of joint venture	  	 	389	 	  	 	168	 	
 	  	 	–	 	  	 	–	 	
Operating profit	  	 	(84)	 	  	 	(989)	 	
 	  	 	 	 	  	 	 	 	
Depreciation and amortization	  	 	2,568	 	  	 	1,910	 	
Corporate research and development	  	 	509	 	  	 	567	 	
Corporate headquarter costs	  	 	2,073	 	  	 	1,738	 	
Other operating income (expense)	  	 	(437)	 	  	 	(734)	 	
 	 	 	
Segment EBITDA	  	 	4,629	 	  	 	2,492	 	

SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

MATERIALISE NV	
 	 	
By:	 	/s/ Wilfried Vancraen	
Name:	 	Wilfried Vancraen	
Title:	 	Chief Executive Officer	
Date: May 9, 2017