ExOne (XONE) 8-K Changes in Registrant's Certifying Accountant

Exhibit 16.1

March 25, 2016

Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Ladies and Gentlemen:

We have read Item 4.01 of Form 8-K, dated on or about March 24, 2016, of The ExOne Company and agree with the statements contained in the second and third paragraphs therein. We have no basis to agree or disagree with other statements of the registrant contained therein.

Very truly yours,

/s/ Baker Tilly Virchow Krause, LLP