Exhibit EX-99

99.1

Announcement on 2015/08/27: To announce accumulative shares repurchased exceeding NTD$300 million in value

99.2

Announcement on 2015/09/02: UMC will attend investor conferences on 2015/09/09

99.3

Announcement on 2015/09/02: Represent subsidiary United Semiconductor (Xiamen) Co., Ltd.to announce related materials on acquisition of facilities and equipment

99.4

Announcement on 2015/09/03: To announce accumulative shares repurchased exceeding NTD$300 million in value

99.5

Announcement on 2015/09/10: To announce accumulative shares repurchased exceeding NTD$300 million in value

99.6

Announcement on 2015/09/11: To announce related materials on acquisition of machinery and equipment

99.7

Announcement on 2015/09/15: To announce the completion of share buy-back program

99.9

Announcement on 2015/09/15: the trading and pledge of UMC common shares by directors, executive officers and 10% shareholders of UMC

To announce accumulative shares repurchased exceeding NTD$300 million in value

Date the cumulative number of shares repurchased in the current repurchase accounted for 2 percent or more of the shares issued by the company or the cumulative value of shares repurchased amounted to NT$300 million or more:2015/08/27

Cumulative number of own shares held during the repurchase period: 120,000,000 shares

Ratio of cumulative number of own shares held during the repurchase period to the total number of the Company’s issued shares: 0.94

1. Date of the investor conference: 2015/09/09
2. Time of the investor conference: 09:00 AM
3. Location of the investor conference: Grand Hyatt Hotel, Taipei
4. Brief information disclosed in the investor conference:

The Company will attend the “Asian Technology Conference 2015” conference, held by Credit Suisse.

Represent subsidiary United Semiconductor (Xiamen) Co., Ltd.to announce related materials on
acquisition of facilities and equipment

1. Name and nature of the subject matter (e.g. land located at Sublot XX, Lot XX, North District, Taichung City): facilities and equipment
2. Date of the occurrence of the event: 2015/08/01~2015/09/02
3. Transaction volume (e.g. XX square meters, equivalent to XX p’ing), unit price, total transaction price: Transaction volume: one batch; Average unit price: NT$725,759,370; Total transaction price: NT$725,759,370
4. Counterparty to the trade and its relationship with the company (if the trading counterpart is a natural person and is not an actual related party of the Company, the name of the trading counterpart is not required to be disclosed): L&K ENGINEERING (SUZHOU) CO.,LTD; Non-related party transaction
5. Where the counterpart to the trade is an actual related party, a public announcement shall also include the reason for choosing the related party as trading counterpart and the identity of the previous owner (including its relationship with the company and the trading counterpart), price of transfer and the date of acquisition: Not applicable
6. Where a person who owned the property within the past five years has been an actual related person of the company, a public announcement shall also include the dates and prices of acquisition and disposal by the related person and the person’s relationship to the company at those times: Not applicable
7. Anticipated loss or profit from the disposal (not applicable in cases of acquisition of assets) (where originally deferred, the status or recognition shall be stated and explained): Not applicable
8. Terms of delivery or payment (including payment period and monetary amount): Base on purchase order payment term.
9. The manner of deciding on this transaction (such as tender invitation, price comparison, or price negotiation), the reference basis for the decision on price and the decision-making department: Transaction: price negotiation; The reference basis for the decision on price: market price; The decision-making department: the Selection Meeting
10. Name of the professional appraisal institution and its appraisal amount::Not applicable
11. Reason for any significant discrepancy with the transaction amount, and opinion of the certifying CPA: Not applicable
12. Is the appraisal report price a limited price or specific price?: Not applicable
13. Has an appraisal report not yet been obtained?: Not applicable
14. Reason an appraisal report has not yet been obtained: Not applicable
15. Broker and broker’s fee: None
16. Concrete purpose or use of the acquisition or disposition: For production
17. Do the directors have any objection to the present transaction?: Not applicable
18. Any other matters that need to be specified: None

To announce accumulative shares repurchased exceeding NTD$300 million in value

Cumulative number of own shares held during the repurchase period: 153,000,000 shares

Ratio of cumulative number of own shares held during the repurchase period to the total number of the Company’s issued shares: 1.20

To announce accumulative shares repurchased exceeding NTD$300 million in value

Cumulative number of own shares held during the repurchase period: 181,000,000 shares

Ratio of cumulative number of own shares held during the repurchase period to the total number of the Company’s issued shares: 1.42

1. Name and nature of the subject matter (e.g. land located at Sublot XX, Lot XX, North District, Taichung City): Machinery and equipment
2. Date of the occurrence of the event: 2015/08/18~2015/09/11
3. Transaction volume (e.g. XX square meters, equivalent to XX p’ing), unit price, total Transaction volume: one batch; average unit price: $536,377,616 NTD; total transaction price:$ 536,377,616 NTD
4. Counterparty to the trade and its relationship with the company (if the trading counterpart is a natural person and is not an actual related party of the Company, the name of the trading counterpart is not required to be disclosed): Applied Materials South East Asia Pte. Ltd.; non-related party transaction
5. Where the counterpart to the trade is an actual related party, a public announcement shall also include the reason for choosing the related party as trading counterpart and the identity of the previous owner (including its relationship with the company and the trading counterpart), price of transfer and the date of acquisition: Not applicable
6. Where a person who owned the property within the past five years has been an actual related person of the company, a public announcement shall also include the dates and prices of acquisition and disposal by the related person and the person’s relationship to the company at those times: Not applicable
7. Anticipated loss or profit from the disposal (not applicable in cases of acquisition of assets) (where originally deferred, the status or recognition shall be stated and explained): Not applicable
8. Terms of delivery or payment (including payment period and monetary amount): Base on purchase order payment term.
9. The manner of deciding on this transaction (such as tender invitation, price comparison, or price negotiation), the reference basis for the decision on price and the decision-making department: transaction: price negotiation; the reference basis for the decision on price: market price. The decision-making department: the Selection Meeting
10. Name of the professional appraisal institution and its appraisal amount: Not applicable
11. Reason for any significant discrepancy with the transaction amount, and opinion of the certifying CPA: Not applicable
12. Is the appraisal report price a limited price or specific price? : Not applicable
13. Has an appraisal report not yet been obtained? : Not applicable
14. Reason an appraisal report has not yet been obtained: Not applicable
15. Broker and broker’s fee: None
16. Concrete purpose or use of the acquisition or disposition: For production
17. Do the directors have any objection to the present transaction?: Not applicable
18. Any other matters that need to be specified: None

1. Originally determined ceiling on total monetary amount of the share repurchase: NTD$78,649,941,000
2. Original scheduled period for the repurchase: 2015/07/30~2015/09/29
3. Originally determined number of shares to be repurchased: A maximum of 200,000,000 shares
4. Originally determined repurchase price range: NTD$7.55 to NTD$18.80 per share.
5. Date of expiry of the repurchase period or completion of the repurchase: 2015/09/15
6. Number of shares repurchased: 200,000,000 shares
7. Total monetary amount of shares repurchased: NTD$2,203,442,499
8. Average repurchase price per share: NTD$11.02
9. Cumulative number of own shares held: 334,223,500 shares
10. Ratio of cumulative number of own shares held during the repurchase period

This is to report the changes or status of 1) Sales volume, 2) Funds lent to other parties, 3) Endorsements and guarantees, and 4) Financial derivative transactions for the period of August 2015.


Period	Items	2015		2014		Changes		%
August	Net sales		12,190,856		11,415,416		775,440		6.79	%
Year-to-Date	Net sales		100,555,983		90,520,348		10,035,635		11.09	%

Last Month

This Month

(actual amount

Balance as of period end

(actual amount provided)

provided)

Limit of lending

UMC

1,700,000

44,134,945

Note : On December 24, 2014, the board of directors resolved to provide endorsement to Nexpower’s syndicated loan from banks including Bank of Taiwan for the amount up to NT$ 17,400 million.

This is to report 1) the trading of directors, executive officers and 10% shareholders of United Microelectronics Corporation (“UMC”) (NYSE: UMC); 2) the pledge and clear of pledge of UMC common shares by directors, executive officers and 10% shareholders of UMC;

Number of shares as

Number of shares as of

Title

Name

of July 31, 2015

August 31, 2015

Changes

The pledge and clear of pledge of UMC common shares by directors, executive officers and 10% shareholders:

Number of shares

pledged as of

Title

Name

July 31, 2015

August 31, 2015

Changes

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