SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

Amendment No. 1

FORM 10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

FOR THE QUARTERLY PERIOD ENDED JUNE 30, 2014

COMMISSION FILE NUMBER 0-12422

MAINSOURCE FINANCIAL GROUP, INC.

(Exact name of registrant as specified in its charter)

(812) 663-6734

(Registrant’s telephone number, including area code)

N/A

(Former name, former address and former fiscal year, if changed since last report.)

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 x No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, 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 x No o

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 definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

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

As of November 8, 2013 there were outstanding 20,403,933 shares of common stock, without par value, of the registrant.

EXPLANATORY NOTE

The purpose of this Amendment No. 1 on Form 10-Q/A to MainSource Financial Group, Inc.’s quarterly report on Form 10-Q for the quarter ended June 30, 2014, originally filed with the Securities and Exchange Commission on August 8, 2014 (the “Form 10-Q”), is solely to include disclosure pursuant to Item 701 of Regulation S-K which was inadvertently omitted.

No other changes have been made to the Form 10-Q. This Amendment No. 1 speaks as of the original filing date of the Form 10-Q, 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.

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Item 2.  Unregistered Sales of Equity Securities and Use of Proceeds.

(c)                                  Issuer Purchases of Equity Securities

The Company purchased the following equity securities of the Company during the quarter ended June 30, 2014:

(1)                                 Erroneously omitted From the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2014.

(2)                                 Includes 19,078 shares withheld, delivered or attested (under the terms of grants under employee stock compensation plans) to offset tax withholding obligations that occur upon vesting and release of restricted shares. The Company’s employee stock compensation plans provide that the value of the shares withheld, delivered or attested, shall be valued using the fair market value of the Company’s common stock on the date the relevant transaction occurs.

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Item 6. Exhibits

The following exhibits shall not be deemed filed for purposes of Section 18 of the Securities Exchange Act of 1934 and Sections 11 and 12 of the Securities Act of 1933, and are not incorporated by reference into any filing under the Securities Act or the Exchange Act, except to the extent the Company specifically incorporates them by reference.

*Filed herewith.

**Previously furnished with our Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on August 8, 2014.

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MAINSOURCE FINANCIAL GROUP, INC.

FORM 10-Q/A

SIGNATURES

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

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