Initial rating of $1.8 billion commercial paper program

New York, September 19, 2012 — Moody’s Investors Service assigned a Prime-2 rating to Noble Corporation’s (Cayman Islands) (Noble) newly established $1.8 billion commercial paper program. Moody’s also affirmed Noble’s and its rated subsidiaries Baa1 senior unsecured ratings. The rating outlook remains negative.

RATINGS RATIONALE

Borrowings under the new commercial paper program will be used to fund planned capital expenditures and for other general corporate purposes. Alternate liquidity for the full amount of commercial paper outstanding will be provided by Noble’s combined $1.8 billion of committed revolving credit facilities that mature in 2015 and 2017. The credit facilities have a covenant limiting the ratio of debt to total tangible capitalization (as defined in the agreement) to 0.60. At June 30, 2012 the company’s ratio was 0.35, providing significant headroom under this covenant which we expect to be maintained through 2013. The credit facilities do not require representations regarding material adverse changes, litigation or environmental matters as a condition precedent to additional borrowings.

Noble’s Baa1 senior unsecured ratings reflect its large drilling rig fleet, global diversification and strong market position. The company is in the midst of constructing five ultra-deepwater drillships and six high-specification jackups, which will enhance the quality and long-term competitiveness of its drilling fleet. Three of the drillships and one jackup under construction have customer contracts, while the rest are un-contracted and therefore subject to future market demand and dayrate risk.

This heavy capital spending coincided with a period of relatively weak cash flows in 2011, resulting in high leverage metrics that are taking longer than initially anticipated to return to the company’s target levels. Debt/EBITDA at June 30, 2012 was approximately 3.6x versus the company’s long term target of 1.5x – 2x. However, EBITDA has been sequentially increasing this year and Debt/EBITDA on a second quarter 2012 run-rate basis was 2.7x.

Noble’s debt will continue rising through 2013 as the company funds its new rig construction. The negative outlook highlights the risk that earnings may not increase sufficiently over that period to reduce leverage metrics to levels consistent with the Baa1 rating. The ratings could be downgraded if earnings growth falls short of forecasts or if additional newbuild rig commitments are undertaken that require more debt funding. In order for the outlook to return to stable, Debt/EBITDA should be declining towards 2.5x with clear visibility to being sustained under 2.5x. A rating upgrade is unlikely through 2014 given Noble’s high leverage metrics and still rising debt levels.

The principal methodology used in this rating was Global Oilfield Services Rating Methodology published in December 2009. Please see the Credit Policy page on www.moodys.com for a copy of this methodology.

Noble Corporation (Cayman Islands) is a wholly owned subsidiary of Noble Corporation, a publicly traded offshore drilling contractor based in Zug, Switzerland that operates in major offshore markets around the world. Noble’s senior unsecured notes are primarily issued by another subsidiary, Noble Holding International Limited (NHIL), which Noble Corporation (Cayman Islands) fully guarantees. NHIL also fully guarantees the CP and revolver borrowings of Noble (Cayman Islands).

REGULATORY DISCLOSURES

The Global Scale Credit Ratings on this press release that are issued by one of Moody’s affiliates outside the EU are endorsed by Moody’s Investors Service Ltd., One Canada Square, Canary Wharf, London E 14 5FA, UK, in accordance with Art.4 paragraph 3 of the Regulation (EC) No 1060/2009 on Credit Rating Agencies. Further information on the EU endorsement status and on the Moody’s office that has issued a particular Credit Rating is available on www.moodys.com.

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Peter Speer VP – Senior Credit Officer Corporate Finance Group Moody’s Investors Service, Inc.250 Greenwich Street New York, NY 10007 U.S.A. JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653Steven Wood MD – Corporate Finance Corporate Finance Group JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653 Releasing Office: Moody’s Investors Service, Inc.250 Greenwich Street New York, NY 10007 U.S.A. JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653(C) 2012 Moody’s Investors Service, Inc. and/or its licensors and affiliates (collectively, “MOODY’S”). All rights reserved.

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