SCHEDULE 13G

(Rule 13d-102)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(b), (c) AND (d) AND AMENDMENTS THERETO FILED

PURSUANT TO § 240.13d-2.

(Amendment No.     )*

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

** Heights Capital Management, Inc. is the investment manager to Capital Ventures International and as such may exercise voting and dispositive power over these shares.

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** Heights Capital Management, Inc. is the investment manager to Capital Ventures International and as such may exercise voting and dispositive power over these shares.

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Item 4.                                                         Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

The information required by Items 4(a) — (c) is set forth in Rows 5 — 11 of the cover page for each Reporting Person hereto and is incorporated herein by reference for each such Reporting Person.

The Company’s Prospectus Supplement to the Prospectus, dated July 26, 2015 (Registration No. 333-204024), filed on July 28, 2015, indicates there were 7,232,222 Shares outstanding as of the completion of the offering of the Shares referred to therein.

Heights Capital Management, Inc., which serves as the investment manager to Capital Ventures International, may be deemed to be the beneficial owner of all Shares owned by Capital Ventures International. Each of the Reporting Persons hereby disclaims any beneficial ownership of any such Shares, except for their pecuniary interest therein.

Item 5.                                                         Ownership of Five Percent or Less of a Class

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: o

Item 6.                                                         Ownership of More than Five Percent on Behalf of Another Person

Not applicable.

Item 7.                                                         Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Not applicable.

Item 8.                                                         Identification and Classification of Members of the Group

Not Applicable

Item 9.                                                         Notice of Dissolution of Group

Not applicable.

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Item 10.                                                  Certification

By signing below each of the undersigned certifies that, to the best of its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURES

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information with respect to it set forth in this statement is true, complete, and correct.

Dated: August 5, 2015

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EXHIBIT INDEX

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Exhibit I

LIMITED POWER OF ATTORNEY

THIS LIMITED POWER OF ATTORNEY given on the 3rd day of April, 1999 by Capital Ventures International (hereinafter called “the Company”), whose Registered Office is situated at Second Floor, One Capital Place, P.O. Box 1781, Grand Cayman Islands, B.W.I.

WHEREAS, by agreement dated March 10, 1997, by and between the Company and Heights Capital Management, the Company expressly authorized Heights Capital Management to enter into transactions in certain designated areas as defined in the Agreement attached hereto marked “Appendix 1.”

NOW THIS DEED WITNESSETH that Ian A.N. Wight (Director) and Woodburne Associates (Cayman) Limited (Secretary) of the Company, hereby appoint on behalf of the Company the firm of HEIGHTS CAPITAL MANAGEMENT which through its officers, directors and employees is hereby formally granted limited power of attorney for the purpose of entering into transactions on behalf of and for the account of the Company and to take any actions on behalf of the Company as may be necessary to consummate such transactions, including but not limited to instructing the transfer of funds where necessary and executing required documentation.

IN WITNESS WHEREOF, the Company has caused its common seal to be hereunto affixed the day and year above written.

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EXHIBIT II

JOINT FILING AGREEMENT

This will confirm the agreement by and among the undersigned that the Schedule 13G filed with the Securities and Exchange Commission on or about the date hereof with respect to the beneficial ownership by the undersigned of the shares of Common Stock of Ceres, Inc., $.01 par value per share is being filed, and all amendments thereto will be filed, on behalf of each of the persons and entities named below in accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. This Agreement may be executed 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.

Dated as of August 5, 2015