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A live webcast and replay of the 1Q17 results announcement will be available at www.umc.com under the “Investors / Events” section.

About UMC

UMC (NYSE: UMC, TWSE: 2303) is a leading global semiconductor foundry that provides advanced IC production for applications spanning every major sector of the electronics industry. UMC’s comprehensive foundry solutions enable chip designers to leverage the company’s sophisticated technology and manufacturing, which include high volume 28nm High-K/Metal Gate technology, 14nm FinFET mass production, ultra-low power platform processes specifically developed for Internet of Things (IoT) applications and the automotive industry’s highest-rated AEC-Q100 Grade-0 manufacturing capabilities for the production of ICs found in vehicles. UMC’s 11 wafer fabs are strategically located throughout Asia and are able to produce nearly 600,000 wafers per month. The company employs over 19,000 people worldwide, with offices in Taiwan, China, Europe, Japan, Korea, Singapore, and the United States. UMC can be found on the web at http://www.umc.com

Note from UMC Concerning Forward-Looking Statements

Some of the statements in the foregoing announcement are forward-looking within the meaning of the U.S. Federal Securities laws, including statements about introduction of new services and technologies, future outsourcing, competition, wafer capacity, business relationships and market conditions. Investors are cautioned that actual events and results could differ materially from these statements as a result of a variety of factors, including conditions in the overall semiconductor market and economy; acceptance and demand for products from UMC; and technological and development risks. Further information regarding these and other risks is included in UMC’s filings with the U.S. Securities and Exchange Commission. UMC does not undertake any obligation to update any forward-looking statement as a result of new information, future events or otherwise, except as required under applicable law.

Safe Harbor Statements

This release contains forward-looking statements. These statements constitute “forward-looking” statements within the meaning of Section 27A of the United States Securities Act of 1933, as amended, and Section 21E of the United States Securities Exchange Act of 1934, as amended, and as defined in the United States Private Securities Litigation Reform Act of 1995. You can identify these forward-looking statements by use of words such as “strategy,” “expects,” “continues,” “plans,” “anticipates,” “believes,” “will,” “estimates,” “intends,” “projects,” “goals,” “targets” and other words of similar meaning. You can also identify them by the fact that they do not relate strictly to historical or current facts.

These forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause the actual performance, financial condition or results of operations of UMC to be materially different from what is stated or may be implied in such forward-looking statements. Investors are cautioned that actual events and results could differ materially from those statements as a result of a number of factors including, but not limited to: (i) dependence upon the frequent introduction of new services and technologies based on the latest developments in the industry in which UMC operates; (ii) the intensely competitive semiconductor, communications, consumer electronics and computer industries and markets; (iii) the risks associated with international business activities; (iv) dependence upon key personnel; (v) general economic and political conditions; (vi) possible disruptions in commercial activities caused by natural and human-induced events and disasters, including natural disasters, terrorist activity, armed conflict and highly contagious diseases; (vii) reduced end-user purchases relative to expectations and orders; and (viii) fluctuations in foreign currency exchange rates. Further information regarding these and other risks is included in UMC’s filings with the United States Securities and Exchange Commission. All information provided in this release is as of the date of this release and are based on assumptions that UMC believes to be reasonable as of this date, and UMC does not undertake any obligation to update any forward-looking statement as a result of new information, future events or otherwise, except as required under applicable law.

The financial statements included in this release are prepared and published in accordance with Taiwan International Financial Reporting Standards, or TIFRSs, recognized by the Financial Supervisory Commission in the ROC, which is different from International Financial Reporting Standards, or IFRSs, issued by the International Accounting Standards Board. Investors are cautioned that there may be significant differences between TIFRSs and IFRSs. In addition, TIFRSs and IFRSs differ in certain significant respects from generally accepted accounting principles in the ROC and generally accepted accounting principles in the United States.

This presentation is not an offer of securities for sale in the United States. Securities may not be offered or sold in the United States absent registration or an exemption from registration. Any public offering of securities to be made in the United States will be made by means of a prospectus that may be obtained from the issuer or selling security holder and that will contain detailed information about the company and management, as well as financial statements.

¹ Unless otherwise stated, all financial figures discussed in this announcement are prepared in accordance with TIFRSs recognized by Financial Supervisory Commission in the ROC, which is different from IFRSs issued by the International Accounting Standards Board. They represent comparisons among the three-month period ending Mar 31, 2017, the three-month period ending Dec 31, 2016, and the equivalent three-month period that ended Mar 31, 2016. For all 1Q17 results, New Taiwan Dollar (NT$) amounts have been converted into U.S. Dollars at the Mar 31, 2017 exchange rate of NT$ 30.31 per U.S. Dollar.