Exhibit

Exhibit Description

99.1 Announcement on 2010/03/19: To announce related materials on acquisition of machinery and equipment

99.2 Announcement on 2010/03/19: To announce related materials on acquisition of machinery and equipment

99.3 Announcement on 2010/03/22: To announce related materials on acquisition of machinery and equipment

99.4 Announcement on 2010/03/22: To announce accumulative shares repurchased exceeding NTD$300 million in value

99.5 Announcement on 2010/03/22: To announce the completion of share buy-back program

99.6 Announcement on 2010/03/24: To clarify reports on Commercial Times on March 24, 2010

99.7 Announcement on 2010/03/29: To announce related materials on acquisition of machinery and equipment

99.8 Announcement on 2010/03/31: The expected closing date of the merger by UMC of the holding company of He Jian Technology (Suzhou) Co., Ltd. is inapplicable

99.9 Announcement on 2010/04/06: To announce related materials on acquisition of machinery and equipment

99.10 Announcement on 2010/04/07: To announce related materials on acquisition of machinery and equipment

99.11 Announcement on 2010/04/08: To announce related materials on acquisition of machinery and equipment

99.12 Announcement on 2010/04/08: To announce related materials on acquisition of machinery and equipment

99.13 Announcement on 2010/04/08: To announce related materials on acquisition of machinery and equipment

99.14 Announcement on 2010/04/09: To clarify reports on Economic Daily News on April 9, 2010

99.15 Announcement on 2010/04/12: Represent subsidiary United Lighting Opto-Electronic Inc. to announce related materials on investment of mainland Chinese company

99.16 Announcement on 2010/04/12: Represent subsidiary United Lighting Opto-Electronic Inc. to announce related materials on investment of mainland Chinese company

99.17 Announcement on 2010/04/12: To announce related materials on acquisition of machinery and equipment

99.18 Announcement on 2010/04/14: To announce related materials on acquisition of machinery and equipment

99.19 Announcement on 2010/04/15: To announce related materials on acquisition of Real estate

99.20 Announcement on 2010/04/16: To announce related materials on acquisition of machinery and equipment

99.21 Announcement on 2010/04/08: March Revenue

99.22 Announcement on 2010/04/15: the trading and pledge of UMC common shares by directors, executive officers and 10% shareholders of UMC

Exhibit 99.1

To announce related materials on acquisition of machinery and equipment

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:2010/01/28~2010/03/19
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: $528,890,919NTD;total transaction price: $528,890,919NTD
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):TOKYO ELECTRON LIMITED; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.2

To announce related materials on acquisition of machinery and equipment

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:2009/05/15~2010/03/19
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: $1,779,520,935NTD;total transaction price: $1,779,520,935NTD
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 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.3

To announce related materials on acquisition of machinery and equipment

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:2009/03/19~2010/03/22
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: $638,559,600NTD;total transaction price: $638,559,600NTD
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; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.4

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

Date of events:2010/03/22

Contents:

1.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:2010/03/22

2.Number of shares repurchased this time: 18,915,000 shares

3.Type of shares repurchased this time: Common share

4.Total monetary amount of shares repurchased this time: NTD$ 317,392,962

5.Average repurchase price per share this time: NTD$16.78

6.Cumulative number of own shares held during the repurchase period:300,000,000 shares

7.Ratio of cumulative number of own shares held during the repurchase period to the total number of the Company’s issued shares: 2.31

8.Any other matters that need to be specified: None

Exhibit 99.5

To announce the completion of share buy-back program

Date of events:2010/03/22
1.Originally determined ceiling on total monetary amount of the share repurchase: NTD$50,561,081,000
2.Original scheduled period for the repurchase: 2010/02/03~2010/04/02
3.Originally determined number of shares to be repurchased:A maximum of 300,000,000 shares
4.Originally determined type of shares to be repurchased: Common shares
5.Originally determined repurchase price range:NTD$10.95 to NTD$25.85 per share.
6.Date of expiry of the repurchase period or completion of the repurchase: 2010/03/22
7.Number of shares repurchased: 300,000,000 shares
8.Type of shares repurchased: Common shares
9.Total monetary amount of shares repurchased: NTD$4,843,587,820
10.Average repurchase price per share: NTD$16.15
11.Cumulative number of own shares held: 521,909,000 shares
12.Ratio of cumulative number of own shares held during the repurchase period to the total number of the Company’s issued shares: 4.02%
13.Reason for non-completion of the share repurchase at expiry of the repurchase period: Not applicable
14.Any other matters that need to be specified: None.

Exhibit 99.6

To clarify reports on Commercial Times on March 24, 2010

Date of events:2010/03/24
1.Name of the reporting media: Commercial Times, A1
2.Date of the report:2010/03/24
3.Content of the report:UMC kicks-off the plan to merge HeJian. The Board Meeting will discuss the revised exchange ratio, including 15% cash and 85% of treasury shares in April.
4.Summary of the information provided by investors: None
5.Company’s explanation of the reportage or provided information:The Company here to clarify that the news was derived from speculation. Regarding to the plan and progress of the merger, please refer to the public annoucements on MOPS.
6.Countermeasures: None
7.Any other matters that need to be specified: None

Exhibit 99.7

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:2010/01/05~2010/03/29
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: $818,806,800NTD;total transaction price: $818,806,800NTD
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):KLA-TENCOR CORPORATION; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.8

The expected closing date of the merger by UMC of the holding company of He Jian Technology (Suzhou) Co., Ltd. is inapplicable.
1.Date of occurrence of the event:2010/03/31
2.Date of the original public announcement and reporting:2009/04/29
3.Summary of the content originally publicly announced and reported:Board approved to propose the merger by UMC of the holding company of He Jian Technology (Suzhou) Co., Ltd.
4.Reason for, and major content of, the change:
After the ROC laws and regulations with respect of investments in China have been amended, UMC is in process of preparing documents in connection with the merger by UMC of the holding company of He Jian Technology (Suzhou) Co., Ltd., Infoshine Technology Limited, so as to apply with governmental authorities for approvals. The closing date of this merger, which was expected to occur on or before December 31, 2009 and automatically extended to March 31, 2010 pursuant to the Agreement and Plan of Merger, is inapplicable. The actual closing date of this merger will be determined based on the progress of this merger and will be announced in accordance with the applicable laws and regulations.
5.Effect on the Company’s finances and business after the change:None
6.Any other matters that need to be specified:None

Exhibit 99.9

To announce related materials on acquisition of machinery and equipment

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:2010/04/02~2010/04/06
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: $598,372,320NTD;total transaction price: $598,372,320NTD
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):KLA-TENCOR CORPORATION; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.10

To announce related materials on acquisition of machinery and equipment

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:2010/04/06~2010/04/07
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: $ 763,440,000NTD;total transaction price: $763,440,000NTD
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):KLA-TENCOR CORPORATION; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.11

To announce related materials on acquisition of machinery and equipment

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:2010/03/21~2010/04/08
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: $ 608,772,000NTD;total transaction price: $608,772,000NTD
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; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.12

To announce related materials on acquisition of machinery and equipment

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:2009/04/28~2010/04/08
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: $ 712,240,655NTD;total transaction price: $712,240,655NTD
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):NISSIN ION EQUIPMENT 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.13

To announce related materials on acquisition of machinery and equipment

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:2009/11/11~2010/04/08
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: $ 560,366,266NTD;total transaction price: $ 560,366,266NTD
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):Novellus Systems International; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.14

To clarify reports on Economic Daily News on April 9, 2010

1.Name of the reporting media: Economic Daily News, A15
2.Date of the report:2010/04/09
3.Content of the report:UMC suspended the issuance of the NT$10bn corporate bonds
4.Summary of the information provided by investors: None
5.Company’s explanation of the reportage or provided information:
The planned issuance of unsecured corporate bonds is authorized by the Board of Directors and can proceed according to the market situation, laws, and the authorities regulation. In order to fulfill capital needs for future operation and growth, the Company is still evaluating each funding instrument. Further progress will be announced on MOPS as required.
6.Countermeasures: None
7.Any other matters that need to be specified: None

Exhibit 99.15

Represent subsidiary United Lighting Opto-Electronic Inc. to announce related materials on investment of mainland Chinese company
1.Date of occurrence of the event:2010/04/12
2.Date of the original public announcement and reporting:2009/12/23
3.Summary of the content originally publicly announced and reported:
To invest mainland Chinese company U-Lighting Opto-Electronic (Shan Dong) Inc. through UNITED LIGHTING OPTO-ELECTRONIC INVESTMENT (HK) LIMITED.
4.Reason for, and major content of, the change:
The Investment of the mainland Chinese company U-Lighting Opto-Electronic (Shan Dong) Inc. through UNITED LIGHTING OPTO-ELECTRONIC INVESTMENT (HK) LIMITED approved on 2009/12/23 was canceled by the resolution of Board of Directors on 2010/4/12.
5.Effect on the Company’s finances and business after the change:None
6.Any other matters that need to be specified:None

Exhibit 99.16

Represent subsidiary United Lighting Opto-Electronic Inc. to announce related materials on investment of mainland Chinese company
1.Date of occurrence of the event:2010/04/12
2.Method of the present increase (decrease) in investment:
Invest mainland Chinese company PIONEER U-LIGHTING OPTO-ELECTRONIC Inc.by UNITED LIGHTING OPTO-ELECTRONIC INVESTMENT (HK) LIMITED
3.Transaction volume, price per unit, and total monetary amount of the transaction:Not exceeding USD$1,000,000
4.Company name of the invested mainland Chinese company:
PIONEER U-LIGHTING OPTO-ELECTRONIC Inc.
5.Paid-in capital of said invested mainland Chinese company:USD$0 before capital increase
6.Amount of new capital increment currently planned by said invested mainland Chinese company:
USD$1,500,000
7.Main business items of said invested mainland Chinese company: LED lighting manufacturing and sale.
8.Type of CPA opinion issued for the financial statement of said invested mainland Chinese company for the most recent fiscal year:Not applicable
9.Net worth of said invested mainland Chinese company on the financial statement for the most recent fiscal year:Not applicable
10.Amount of profit/loss of said invested mainland Chinese company on the financial statement for the most recent fiscal year:Not applicable
11.Amount of actual investment to date in said invested mainland Chinese company:0
12.Counterparty to the transaction and its relationship to the Company: Not applicable
13.Where the counterparty to the transaction is an actual related party, public announcement shall also be made of the reason for choosing the related party as the counterparty and the identity of the previous owner (including its relationship with the company and the trading counterpart), the date of transfer, and the price:Not applicable
14.Where a person who owned the subject matter of the transaction within the past five years has been an actual related party of the company, public announcement shall also be made of the dates and prices of acquisition and disposal by the related party and such party’s relationship to the company at those times: Not applicable
15.Gain (or loss) on disposal: Not applicable
16.Terms of delivery or payment (including payment period and monetary amount), restrictive covenants in the contract, and other important stipulations:One-time payment; None
17.The manner of deciding on this transaction, the reference basis for the decision on price and the decision-making department:By the Board of Directors
18.Broker: None
19.Concrete purpose of the acquisition or disposal:Long-term investment
20.Do the directors have any objection to the present transaction?: None
21.Total amount of mainland China area investment (including the present investment) approved by the Investment Commission to date: USD$0
22.Ratio of the total amount of investment (including the present investment) in the mainland China area approved by the Investment Commission to date to the paid-in capital on the financial statement for the most recent period:0%
23.Ratio of the total amount of investment (including the present investment) in the mainland China area approved by the Investment Commission to date to the total assets on the financial statement for the most recent period:0%
24.Ratio of the total amount of investment (including the present investment) in the mainland China area approved by the Investment Commission to date to the shareholders’ equity on the financial statement for the most recent period:0%
25.Total amount of actual investment in the mainland China area to date:USD$0
26.Ratio of the total amount of actual investment in the mainland China area to date to the paid-in capital on the financial statement for the most recent period: 0%
27.Ratio of the total amount of actual investment in the mainland China area to date to the total assets on the financial statement for the most recent period:0%
28.Ratio of the total amount of actual investment in the mainland China area to date to the shareholders’ equity on the financial statement for the most recent period: 0%
29.Amount of recognized profits and losses on investment in the mainland China area for the most recent three fiscal years:USD$0
30.Amount of profit remitted back to Taiwan for the most recent three fiscal years: USD$0
31.Has the CPA issued an opinion on the unreasonableness of the price of the current transaction?: None
32.Any other matters that need to be specified:None

Exhibit 99.17

To announce related materials on acquisition of machinery and equipment

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:2010/04/08~2010/04/12
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: $ 806,235,500NTD;total transaction price: $806,235,500NTD
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; 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.18

To announce related materials on acquisition of machinery and equipment

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:2010/02/26~2010/04/14
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: $ 1,497,127,044NTD;total transaction price: $ 1,497,127,044NTD
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):ASML HONG KONG 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.19

To announce related materials on acquisition of Real estate

1.Name and nature of the subject matter (e.g.land located at Sublot XX, Lot XX, North District, Taichung City):Chong Hong Suntech City (No. 401 Land, Small Section 4, XiHu Section, Neihu District, Taipei, and the 8-9th floors and underground parking spots for No. 66 and 68, Section 1, Neihu Rd.)
2.Date of the occurrence of the event:2010/04/15
3.Transaction volume (e.g.XX square meters, equivalent to XX p’ing), unit price, total transaction price:Transaction volume: Land area 166.86 ping ,total building area 1,453.13 ping ,Unit price per ping :NT$468,000 , calculating based on total building area,Total transaction price: T$680,000,000
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):Chong Hong Construction 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):
First term payment:Deposit of NT$20,400,000
Second term payment:Deliver NT$81,600,000 at time of contract signing
Third term payment:Deliver NT$68,000,000 at time of stamping
Fourth term payment:Deliver NT$34,000,000 at time of tax payment completion
Fifth term payment: Deliver NT$476,000,000 at time of handover of building to new owners
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:Comparing with Negotiation, valuation reports provided by appraisal authorities, chairman and chief executive officers’offices
10.Name of the professional appraisal institution and its appraisal amount:Euro-Asia Real Estate Appraisers Firm; NT$697,894,950
11.Reason for any significant discrepancy with the transaction amount, and opinion of the certifying CPA:N/A
12.Is the appraisal report price a limited price or specific price?:No
13.Has an appraisal report not yet been obtained?:No
14.Reason an appraisal report has not yet been obtained:N/A
15.Broker and broker’s fee:No
16.Concrete purpose or use of the acquisition or disposition:In response to Taipei branch office’s future moving needs.
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.20

To announce related materials on acquisition of machinery and equipment

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:2010/04/15~2010/04/16
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: $ 1,073,754,320NTD;total transaction price: $1,073,754,320NTD
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):ASML HONG KONG 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):1)90% paid upon shipment;10% paid after acceptance 2)100% paid after acceptance
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:Not applicable
16.Concrete purpose or use of the acquisition or disposition:To produce integrated circuits
17.Do the directors have any objection to the present transaction?:No
18.Any other matters that need to be specified:None

Exhibit 99.21

United Microelectronics Corporation
March 8, 2010

This is to report the changes or status of 1) Sales volume 2) Funds lent to other parties 3) Endorsements and guarantees 4) Financial derivative transactions for the period of March 2010.

1) Sales volume (NT$ Thousand)

Period		Items	2010		2009		Changes		%
March		Invoice amount		6,830,100		3,890,207		2,939,893		75.57	%
	2010	Invoice amount		19,039,792		8,925,625		10,114,167		113.32	%
March		Net sales		9,479,926		4,541,317		4,938,609		108.75	%
	2010	Net sales		26,715,230		10,838,136		15,877,094		146.49	%

2) Funds lent to other parties (NT$ Thousand)

Balance as of period end	This Month		Last Month		Limit of lending
UMC		0		0		25,975,825
UMC’s subsidiaries		0		0		0

3) Endorsements and guarantees (NT$ Thousand)

	Change in This Month		Balance as of period end		Limit of endorsements
UMC		0		0		51,951,649
UMC’s subsidiaries		0		0		0
UMC endorses for subsidiaries				0		0
UMC’s subsidiaries endorse for UMC				0		0
UMC endorses for PRC companies				0		0
UMC’s subsidiaries endorse for PRC companies				0		0

4) Financial derivatives transactions

a Hedging purpose : NT$ thousand
UMC

Financial instruments	Forwards			IRS
Deposit Paid		0			0
Royalty Income (Paid)		0			0
Unwritten-off Trading Contracts		6,274,620			7,500,000
Fair Value		2,928			88,535
Net Profit from Fair Value		(72,437	)		125
Written-off Trading Contracts		27,727,968			7,500,000
Realized profit (loss)		122,653			0

b Trading purpose : NT$
thousand
UMC’s subsidiaries
Financial instruments	ECB Investment - Embedded derivatives
Deposit Paid		0
Royalty Income (Paid)		0
Unwritten-off Trading Contracts		50,000
Fair Value		36,267
Net Profit from Fair Value		0
Written-off Trading Contracts		0
Realized profit (loss)		0

Exhibit 99.22

United Microelectronics Corporation
For the month of March, 2010

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;

1) The trading of directors, supervisors, executive officers and 10% shareholders

Title Name Number of shares
held as of
February 28, 2010 Number of shares held as
of
March 31, 2010

Changes

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

		Number of shares	Number of shares held as
		held as of	of
Title	Name	February 28, 2010	March 31, 2010	Changes