UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 1

to

Form 10-Q

For the quarterly period ended March 31, 2013

OR

For the transition period from                      to                     

Commission file number: 001-35905

BIOAMBER INC.

(Exact name of registrant as specified in its charter)

Jean-François Huc

President and Chief Executive Officer

BioAmber Inc.

1250 Rene Levesque West, Suite 4110

Montreal, Quebec, Canada H3B 4W8

Telephone: (514) 844-8000

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

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  x

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted 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  x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

As of May 13, 2013, there were 18,412,815 shares of the registrant’s Common Stock, $0.01 par value per share, outstanding.

EXPLANATORY NOTE

This Amendment No. 1 to our Quarterly Report on Form 10-Q for the period ended March 31, 2013 is being filed solely for the purpose of furnishing Exhibit 101 to the Form 10-Q which contains the XBRL (Extensible Business Reporting Language) information. As permitted by Rule 405(a)(2)(ii) of Regulation S-T, Exhibit 101 was required to be furnished by amendment within 30 days of the original filing date of the Form 10-Q.

No information contained within the Form 10-Q previously filed on May 15, 2013 has changed. This Amendment No. 1 speaks as of the original filing date of the Form 10-Q, and does not reflect events that may have occurred subsequent to the original filing date and does not modify or update in any way, disclosures made in the original Form 10–Q.

Pursuant to Rule 406T of Regulation S-T, the interactive data files on Exhibit 101 hereto are deemed not “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to liability under that section.

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SIGNATURES

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 hereunto duly authorized.