Ensco plc to Acquire Atwood Oceanics, Inc.

Strengthens Position as Leading Offshore Driller
Adds High-Quality
Portfolio of Floater and Jackup Assets
$65 Million of Annual
Expense Synergies Anticipated from Transaction
Complementary Fleet
Composition and Geographic Presence
Largest Customer Base of Any
Offshore Driller
Well Capitalized with Adjusted Combined Liquidity
of $3.9 Billion

LONDON & HOUSTON–(BUSINESS WIRE)–Ensco plc (NYSE: ESV) and Atwood Oceanics, Inc. (NYSE: ATW) jointly
announced today that they have entered into a definitive merger
agreement under which Ensco will acquire Atwood in an all-stock
transaction. The definitive merger agreement was unanimously approved by
each company’s board of directors.

Under the terms of the merger agreement, Atwood shareholders will
receive 1.60 shares of Ensco for each share of Atwood common stock for a
total value of $10.72 per Atwood share based on Ensco’s closing share
price of $6.70 on 26 May 2017. This represents a premium of
approximately 33% to Atwood’s closing price on the same date. Upon close
of the transaction, Ensco and Atwood shareholders will own approximately
69% and 31%, respectively, of the outstanding shares of Ensco plc. There
are no financing conditions for this transaction.

Ensco expects to realize annual pre-tax expense synergies of
approximately $65 million for full year 2019 and beyond. The combination
is expected to be accretive on a discounted cash flow basis.

Ensco Chief Executive Officer Carl Trowell said, “The combination of
Ensco and Atwood will strengthen our position as the leader in offshore
drilling across a wide range of water depths around the world – creating
a broad platform that we can build upon in the future. This acquisition
significantly enhances our high-specification floater and jackup fleets,
adding technologically advanced drillships and semisubmersibles, and
refreshing our premium jackup fleet to best position ourselves for the
market recovery. We believe that the purchase price for these assets
represents a compelling value to our shareholders, which is augmented
further by expected synergies from the transaction.”

Mr. Trowell added, “By bringing together our high-specification rig
fleets, technology and innovation, and talented rig crews, we plan to
continue delivering high levels of operational and safety performance to
an even larger group of clients. We will remain one of our industry’s
best capitalized companies. Our combined financial strength, diverse
customer base and larger scale should lead to greater strategic and
competitive advantages as well as cost efficiencies, allowing for
opportunistic investments through the market cycle.”

Atwood’s Chief Executive Officer Rob Saltiel stated, “The combination is
an ideal strategic fit. Both companies are passionate about operational
excellence, safety and customer satisfaction with core values and
cultures that are perfectly aligned. We believe the combined company
will offer an unmatched rig fleet and workforce. These attributes,
anchored by a strong balance sheet, should enable the company to thrive
as market conditions improve and allow Atwood shareholders to fully
participate in the market recovery.”

Strategic Fit

The transaction will join two leading offshore drillers – combining
long-established histories of operational, safety and technical
expertise with high-quality assets that cover the world’s most prolific
offshore drilling basins.

The acquisition will strengthen Ensco’s position as the leading offshore
driller with exposure to deep- and shallow-water markets that span six
continents. Upon closing, Ensco will add six ultra-deepwater floaters,
including four of the most capable drillships in the industry, and five
high-specification jackups. The combined company will have a fleet of 63
rigs, comprised of ultra-deepwater drillships, versatile deep- and
mid-water semisubmersibles and shallow-water jackups, along with a
diverse customer base of 27 national oil companies, supermajors and
independents.

Combined Company Highlights

The combined company’s fleet will be among the most technologically
advanced in the industry and will meet the deep- and shallow-water
drilling requirements of an expanded base of clients around the world.
Within the fleet of 26 floating rigs (semisubmersibles and drillships)
are 21 ultra-deepwater drilling rigs, capable of drilling in water
depths of 7,500′ or greater, with an average age of five years –
establishing this fleet among the youngest and most capable in the
industry.

The jackup fleet will be the largest in the world, composed of 37 rigs,
including 27 premium units. These jackups are all equipped with many of
the advanced features requested by clients for shallow-water drilling
programs, such as increased leg length, expanded cantilever reach,
greater hoisting capacity and offline handling capabilities.

The combined company will be among the most geographically diverse
drillers with current operations and drilling contracts spanning six
continents in nearly every major deep- and shallow-water basin around
the world. Regions will include major markets such as the Gulf of
Mexico, Brazil, West Africa, Middle East, North Sea, Mediterranean and
Asia Pacific.

Customers will include most of the leading national and international
oil companies, plus many independent operators. In total, the combined
company will benefit from a diversified client base with the largest
number of current customers of any offshore driller.

Ensco’s executive management will continue with Carl Trowell as
President and Chief Executive Officer, Carey Lowe as Executive Vice
President and Chief Operating Officer, and Jon Baksht as Senior Vice
President and Chief Financial Officer.

Ensco plc’s Chairman will continue to be Paul Rowsey and the board of
directors will include Carl Trowell, plus two members from Atwood’s
current board effective at closing.

Ensco will continue to be domiciled in the UK and senior executive
officers will be located in London and Houston. Ensco plc shares will
continue to trade on the New York Stock Exchange under the symbol “ESV”.

Financial Highlights

Future revenue growth opportunities are anticipated with an expanded
fleet serving a larger customer base across a wide geographic footprint.
While current market conditions are challenging, Ensco will be ideally
positioned to meet increasing levels of customer demand as the market
recovers.

Annual expense savings of $65 million are estimated to be realized in
full year 2019 and beyond, and 2018 cost synergies are projected to be
more than $45 million. Expense savings are anticipated from the
consolidation of offices that include corporate staff departments and
shore-based operations in overlapping markets, as well as the
standardization of systems, policies and procedures across the
organization.

Based on the anticipated annual savings, the planned combination is
expected to be accretive to projected discounted cash flows.

The balance sheet of the combined company will remain strong. Adjusted
for the expected retirement of Atwood’s outstanding revolving credit
facility with cash and short-term investments on hand, total available
liquidity was $3.9 billion on 31 March 2017 and included $1.6 billion of
cash and short-term investments.

The estimated enterprise value of the combined company is $6.9 billion,
based on the closing price of each company’s shares on 26 May 2017. The
combined company will have approximately $3.7 billion in revenue backlog.

Conditions and Timing

The transaction is subject to approval by the shareholders of Ensco and
Atwood, as well as other customary closing conditions. The transaction
is not subject to any financing conditions. Ensco and Atwood intend to
file a joint proxy statement/prospectus with the Securities and Exchange
Commission as soon as possible. The companies anticipate that the
transaction could close as soon as calendar third quarter 2017.

Advisors

Morgan Stanley & Co. LLC is lead financial advisor to Ensco. DNB
Markets, part of DNB Bank ASA and HSBC Securities (USA) Inc. also
provided financial advice to Ensco. Ensco’s legal advisor is Latham
Watkins LLP. The financial advisor for Atwood is Goldman Sachs & Co. LLC
and its legal advisor is Gibson, Dunn & Crutcher LLP.

Conference Call/Webcast

Ensco and Atwood will conduct a conference call to discuss the proposed
acquisition today at 10:00 a.m. CDT (11:00 a.m. EDT and 4:00 p.m. London
time). The call will be webcast live at www.enscoplc.com
and www.atwd.com.
Alternatively, callers may dial 1-855-239-3215 within the United States
or +1-412-542-4130 from outside the U.S. Please ask for the Ensco
conference call. It is recommended that participants call 20 minutes
ahead of the scheduled start time. Callers may avoid delays by
pre-registering to receive a dial-in number and PIN at http://dpregister.com/10108374.

Shortly before the conference call begins, slides will be posted under
the investor relations sections of each company’s website that will be
referred to during the call.

A webcast replay and transcript of the call will be available within 36
hours at www.enscoplc.com
and www.atwd.com.
A replay will also be available by phone for six days after the call by
dialling 1-877-344-7529 within the United States or +1-412-317-0088 from
outside the U.S. (conference ID 10108374).

ABOUT ENSCO

Ensco plc (NYSE: ESV) brings energy to the world as a global provider of
offshore drilling services to the petroleum industry. For more than 29
years, the company has focused on operating safely and going beyond
customer expectations. Ensco is ranked first in total customer
satisfaction in the latest independent survey by EnergyPoint Research —
the seventh consecutive year that Ensco has earned this distinction.
Operating one of the newest ultra-deepwater rig fleets and a leading
premium jackup fleet, Ensco has a major presence in the most strategic
offshore basins across six continents. Ensco plc is an English limited
company (England No. 7023598) with its corporate headquarters located at
6 Chesterfield Gardens, London W1J 5BQ. To learn more, visit our website
at www.enscoplc.com.

ABOUT ATWOOD

Atwood Oceanics, Inc. (NYSE:ATW) is a leading offshore drilling company
engaged in the drilling and completion of exploration and development
wells for the global oil and gas industry. The Company currently owns 9
mobile offshore drilling units and is constructing two ultra-deepwater
drillships. The Company was founded in 1968 and is headquartered in
Houston, Texas. For more information about the Company, please visit www.atwd.com.

Forward-Looking Statements

Statements included in this release regarding the proposed
transaction, benefits, expected synergies and other expense savings and
operational and administrative efficiencies, opportunities, timing,
expense and effects of the transaction, financial performance, accretion
to discounted cash flows, revenue growth, future dividend levels, credit
ratings or other attributes of Ensco plc (“Ensco”) following the
completion of the transaction and other statements that are not
historical facts, are forward-looking statements (including within the
meaning of Section 21E of the Securities Exchange Act of 1934, as
amended, and Section 27A of the Securities Act of 1933, as amended). Forward-looking
statements include words or phrases such as “anticipate,” “believe,”
“contemplate,” “estimate,” “expect,” “intend,” “plan,” “project,”
“could,” “may,” “might,” “should,” “will” and words and phrases of
similar import. These statements involve risks and uncertainties
including, but not limited to, actions by regulatory authorities, rating
agencies or other third parties, actions by the respective companies’
security holders, costs and difficulties related to integration of
Atwood Oceanics, Inc. (“Atwood”), delays, costs and difficulties related
to the transaction, market conditions, and Ensco’s financial results and
performance following the completion of the transaction, satisfaction of
closing conditions, ability to repay debt and timing thereof,
availability and terms of any financing and other factors detailed in
the risk factors section and elsewhere in Ensco’s and Atwood’s Annual
Report on Form 10-K for the year ended December 31, 2016 and September
30, 2016, respectively, and their respective other filings with the
Securities and Exchange Commission (the “SEC”), which are available on
the SEC’s website at www.sec.gov.
Should one or more of these risks or uncertainties materialize (or
the other consequences of such a development worsen), or should
underlying assumptions prove incorrect, actual outcomes may vary
materially from those forecasted or expected. All information in
this release is as of today. Except as required by law, both
Ensco and Atwood disclaim any intention or obligation to update publicly
or revise such statements, whether as a result of new information,
future events or otherwise.

Important Additional Information Regarding the Transaction Will Be
Filed With the SEC

In connection with the proposed transaction, Ensco will file a
registration statement on Form S-4, including a joint proxy
statement/prospectus of Ensco and Atwood, with the SEC. INVESTORS AND
SECURITY HOLDERS OF ENSCO AND ATWOOD ARE ADVISED TO CAREFULLY READ THE
REGISTRATION STATEMENT AND PROXY STATEMENT/PROSPECTUS (INCLUDING ALL
AMENDMENTS AND SUPPLEMENTS THERETO) WHEN THEY BECOME AVAILABLE BECAUSE
THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE TRANSACTION, THE
PARTIES TO THE TRANSACTION AND THE RISKS ASSOCIATED WITH THE
TRANSACTION. A definitive joint proxy statement/prospectus will be sent
to security holders of Ensco and Atwood in connection with the Ensco and
Atwood shareholder meetings. Investors and security holders may obtain a
free copy of the joint proxy statement/prospectus (when available) and
other relevant documents filed by Ensco and Atwood with the SEC from the
SEC’s website at www.sec.gov.
Security holders and other interested parties will also be able to
obtain, without charge, a copy of the joint proxy statement/prospectus
and other relevant documents (when available) by directing a request by
mail or telephone to either Investor Relations, Ensco plc, 5847 San
Felipe, Suite 3300, Houston, Texas 77057, telephone 713-430-4607, or
Investor Relations, Atwood Oceanics, Inc., 15011 Katy Freeway, Suite
800, Houston, Texas 77094, telephone 281-749-7840. Copies of the
documents filed by Ensco with the SEC will be available free of charge
on Ensco’s website at www.enscoplc.com
under the tab “Investors.” Copies of the documents filed by Atwood with
the SEC will be available free of charge on Atwood’s website at www.atwd.com
under the tab “Investor Relations.” Security holders may also read and
copy any reports, statements and other information filed with the SEC at
the SEC public reference room at 100 F Street N.E., Room 1580,
Washington D.C. 20549. Please call the SEC at (800) 732-0330 or visit
the SEC’s website for further information on its public reference room.

Participants in the Solicitation

Ensco and Atwood and their respective directors, executive officers and
certain other members of management may be deemed to be participants in
the solicitation of proxies from their respective security holders with
respect to the transaction. Information about these persons is set forth
in Ensco’s proxy statement relating to its 2017 General Meeting of
Shareholders and Atwood’s proxy statement relating to its 2017 Annual
Meeting of Shareholders, as filed with the SEC on 31 March 2017 and 9
January 2017, respectively, and subsequent statements of changes in
beneficial ownership on file with the SEC. Security holders and
investors may obtain additional information regarding the interests of
such persons, which may be different than those of the respective
companies’ security holders generally, by reading the joint proxy
statement/prospectus and other relevant documents regarding the
transaction, which will be filed with the SEC.

No Offer or Solicitation

This release is not intended to and does not constitute an offer to sell
or the solicitation of an offer to subscribe for or buy or an invitation
to purchase or subscribe for any securities or the solicitation of any
vote in any jurisdiction pursuant to the proposed transaction or
otherwise, nor shall there be any sale, issuance or transfer of
securities in any jurisdiction in contravention of applicable law.
Subject to certain exceptions to be approved by the relevant regulators
or certain facts to be ascertained, the public offer will not be made
directly or indirectly, in or into any jurisdiction where to do so would
constitute a violation of the laws of such jurisdiction, or by use of
the mails or by any means or instrumentality (including without
limitation, facsimile transmission, telephone and the internet) of
interstate or foreign commerce, or any facility of a national securities
exchange, of any such jurisdiction.

Service of Process

Ensco is incorporated under the laws of England and Wales. In addition,
some of its officers and directors reside outside the United States, and
some or all of its assets are or may be located in jurisdictions outside
the United States. Therefore, investors may have difficulty effecting
service of process within the United States upon those persons or
recovering against Ensco or its officers or directors on judgments of
United States courts, including judgments based upon the civil liability
provisions of the United States federal securities laws. It may not be
possible to sue Ensco or its officers or directors in a non-U.S. court
for violations of the U.S. securities laws.

Contacts

Ensco plc
Nick Georgas, 713-430-4607
Director – Investor
Relations and Communications
or
Ensco plc
Tim Richardson,
713-430-4490
Manager – Investor Relations
or
Atwood
Oceanics, Inc.
Mark W. Smith, 281-749-7840
Senior Vice
President and Chief Financial Officer