UMC Announces Share Buyback Amount Exceeds NT$300 Million

1. Date when accumulated repurchased shares reached 2% of issued shares or exceeded NT$300 million: 115/05/11. 2. Number of shares repurchased in this instance (shares): 4,166,000. 3. Total amount of shares repurchased (NT$): 391,855,237. 4. Average price per share repurchased (NT$): 94.06. 5. Accumulated treasury shares held within the buyback period (shares): 8,332,000. 6. Percentage of accumulated treasury shares held to total issued shares (%): 0.07. 7. Other matters to be noted: None.