ENSCO International Ltd

8.01,9.01

Prospectus Supplement for Primary Offering

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Notice of Effectiveness

Notice of Effectiveness

Registration statement under Securities Act of 1933 (amendment)

Registration statement under the Securities Act of 1933 for depositary shares evidenced by American depositary receipts

Registration statement under Securities Act of 1933

FMR LLC