UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 November, 2018

Commission File Number 001-37928

ChipMOS TECHNOLOGIES INC.

(Translation of Registrant’s Name Into English)

No. 1, R&D Rd. 1, Hsinchu Science Park

Hsinchu, Taiwan

Republic of China

(Address of Principal Executive Offices)

(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):  ☐

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, thereunto duly authorized.

ChipMOS REPORTS THIRD QUARTER 2018 RESULTS

Q3’18 Highlights (as compared to Q2’18):

Hsinchu, Taiwan - 11/8/2018 - ChipMOS TECHNOLOGIES INC. (“ChipMOS” or the “Company”) (Taiwan Stock Exchange: 8150 and NASDAQ: IMOS), an industry leading provider of outsourced semiconductor assembly and test services (“OSAT”), today reported unaudited consolidated financial results for the third quarter ended September 30, 2018. All U.S. dollar figures cited in this press release are based on the exchange rate of NT$30.46 against US$1.00 as of September 28, 2018.

All the figures were prepared in accordance with Taiwan-International Financial Reporting Standards (“Taiwan-IFRS”).

Net revenue for the third quarter of 2018 was NT$5,005.2 million or US$164.3 million, an increase of 11.4% from NT$4,491.6 million or US$147.5 million in the second quarter of 2018 and an increase of 13.0% from NT$4,431.1 million or US$145.5 million for the same period in 2017.

Net profit attributable to equity holders of the Company for the third quarter of 2018 was NT$439.6 million or US$14.4 million, and NT$0.56 or US$0.02 per basic common share, as compared to net profit attributable to equity holders of the Company for the second quarter of 2018 of NT$124.1 million or US$4.1 million, and NT$0.15 or US$0.005 per basic common share, and compared to net profit attributable to equity holders of the Company in the third quarter of 2017 of NT$162.0 million or US$5.3 million, and NT$0.19 or US$0.01 per basic common share. Net earnings for the third quarter of 2018 were US$0.37 per basic ADS, compared to US$0.10 per basic ADS for the second quarter of 2018 and US$0.13 per basic ADS in the third quarter of 2017.

S.J. Cheng, Chairman and President of ChipMOS, said, “We are pleased with third quarter results. We achieved 11.4% revenue growth compared to Q2 and improved our gross margin to 19.5% from 16.4% over the same period. We are benefitting from higher utilization levels, a more favorable product mix and higher prices for our services. We expect continued revenue and profit growth led by existing customer programs, higher volume allocations and ongoing competitive share gains. We also continue to benefit from higher customer demand in our TDDI and 12” fine pitch COF businesses. TDDI test demand remains strong as smartphones shift to full screen panels and narrow bezel models, with test programs that run an average of 3 times longer than that of DDIC programs. This puts our capacity at an even higher premium.”

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Silvia Su, Vice President of Finance and Accounting, commented, “ChipMOS is positioned for growth with higher utilization rates, healthy demand in our key markets and a strong balance sheet. We ended the third quarter with a balance of cash and cash equivalents of US$199.2 million, a net debt balance of US$135.2 million, and a net debt to equity ratio of 23.5%. This is after CapEx of $32.8 million in the third quarter, the majority of which was invested to meet higher customer demand levels for our DDIC related capacity, mainly for DDIC wafer test, and our mixed-signal product testing. We finalized our Capital Reduction in October, which reduced our outstanding shares by approximately 15%, and we distributed NT$1.5 per common share to shareholders. Separately, we distributed a cash dividend to shareholders in October of NT$0.3 per common share. Our focus remains on improving profitability and building shareholders’ value.”

Selected Operation Data

Condensed consolidated statements of cash flows

Investor Conference Call / Webcast Details

ChipMOS will host two conference calls on Thursday, November 8, 2018 to discuss the Company’s financial results for the third quarter of 2018.

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About ChipMOS TECHNOLOGIES INC.:

ChipMOS TECHNOLOGIES INC. (“ChipMOS” or the “Company”) (Taiwan Stock Exchange: 8150 and NASDAQ: IMOS) (https://www.chipmos.com) is an industry leading provider of outsourced semiconductor assembly and test services. With advanced facilities in Hsinchu Science Park, Hsinchu Industrial Park and Southern Taiwan Science Park in Taiwan, ChipMOS provide assembly and test services to a broad range of customers, including leading fabless semiconductor companies, integrated device manufacturers and independent semiconductor foundries.

Forward-Looking Statements

This press release may contain certain forward-looking statements. These forward-looking statements may be identified by words such as ‘believes,’ ‘expects,’ ‘anticipates,’ ‘projects,’ ‘intends,’ ‘should,’ ‘seeks,’ ‘estimates,’ ‘future’ or similar expressions or by discussion of, among other things, strategy, goals, plans or intentions. These statements may include financial projections and estimates and their underlying assumptions, statements regarding plans, objectives and expectations with respect to future operations, products and services, and statements regarding future performance. Actual results may differ materially in the future from those reflected in forward-looking statements contained in this document, due to various factors. Further information regarding these risks, uncertainties and other factors are included in the Company’s most recent Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission (the “SEC”) and in the Company’s other filings with the SEC.

About Non-Generally Accepted Accounting Principles (“Non-GAAP”) Financial Measures

To supplement the consolidated financial results presented in accordance with the Taiwan-IFRS, ChipMOS uses non-GAAP free cash flow, non-GAAP earnings before interest, taxes, depreciation and amortization (“EBITDA”) and non-GAAP net debt to equity ratio in this press release. The non-GAAP free cash flow represents operating profit plus depreciation, amortization and interest income and less capital expenditures, interest expense, income tax expense and dividend. The non-GAAP EBITDA represents operating profit plus depreciation and amortization. The non-GAAP net debt to equity ratio represents the ratio of net debt, the sum of debt less cash and cash equivalent, divided by equity attributable to equity holders of the Company. These non-GAAP financial measures may not be comparable to similarly titled measures presented by other companies. Other companies may calculate similarly titled measures differently.

The presentation of non-GAAP financial measures is not intended to be considered in isolation or as a substitute for the financial information prepared and presented in accordance with the Taiwan-IFRS.

ChipMOS considers the use of non-GAAP free cash flow, non-GAAP EBITDA and non-GAAP net debt to equity ratio provides useful information to management to manage the Company’s business and make financial and operational decisions and also to the investors to understand and evaluate the Company’s business and operating performance. For more information on these non-GAAP financial measures, please refer to the table captioned “Reconciliations of Non-GAAP Measures to the Nearest Comparable GAAP Measures” in this press release.

- FINANCIAL TABLES FOLLOW BELOW -

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

For the Three Months Ended Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of U.S. dollars (USD) ⁽¹⁾

Except for Per Share Amounts and Weighted Average Shares Outstanding

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (CONTINUED)

For the Three Months Ended Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of U.S. dollars (USD) ⁽¹⁾

Except for Per Share Amounts and Weighted Average Shares Outstanding

Note:

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

For the Three Months Ended Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of NT dollars (NTD)

Except for Per Share Amounts and Weighted Average Shares Outstanding

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (CONTINUED)

For the Three Months Ended Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of NT dollars (NTD)

Except for Per Share Amounts and Weighted Average Shares Outstanding

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION

As of Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of U.S. dollars (USD) ⁽¹⁾

Note:

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ChipMOS TECHNOLOGIES INC.

UNAUDITED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION

As of Sep. 30, Jun. 30, 2018 and Sep. 30, 2017

Figures in Millions of NT dollars (NTD)

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RECONCILIATIONS OF NON-GAAP MEASURES TO THE NEAREST COMPARABLE GAAP MEASURES

(Figures in Millions of U.S. dollars (USD))

The table below sets forth a reconciliation of our operating profit to non-GAAP free cash flow for the periods indicated:

The table below sets forth a reconciliation of our operating profit to non-GAAP EBITDA for the periods indicated:

The table below sets forth a calculation of our non-GAAP net debt to equity ratio for the periods indicated:

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