Markel and Alterra Shareholders Overwhelmingly Approve Acquisition

  Markel and Alterra Shareholders Overwhelmingly Approve Acquisition

Business Wire

RICHMOND, Va. & HAMILTON, Bermuda -- February 26, 2013

Markel Corporation (NYSE: MKL) ("Markel") and Alterra Capital Holdings Limited
(NASDAQ: ALTE; BSX: ALTE.BH) (“Alterra”) today announced that their respective
shareholders have voted in favor of all proposals necessary for the
acquisition of Alterra by Markel. Completion of the transaction remains
subject to receipt of regulatory approvals and other customary closing
conditions and is expected to occur in the second quarter of 2013.

Under the terms of the merger agreement, each Alterra common share (other than
any shares as to which appraisal rights are exercised or restricted shares
that do not vest in connection with the transaction) is converted into the
right to receive 0.04315 Markel common shares (with cash paid for fractional
shares), plus a cash payment of $10.

Additional information about the acquisition, including the December 19, 2012
announcement press release and a related investor presentation, is posted on
the websites of Markel and Alterra at www.markelcorp.com and
www.alterracap.com, respectively.

About Markel Corporation:

Markel Corporation is a diverse financial holding company serving a variety of
niche markets. The Company's principal business markets and underwrites
specialty insurance products. In each of the Company's businesses, it seeks to
provide quality products and excellent customer service so that it can be a
market leader. The financial goals of the Company are to earn consistent
underwriting and operating profits and superior investment returns to build
shareholder value. Visit Markel Corporation on the web at www.markelcorp.com.

About Alterra Capital Holdings Limited:

Alterra Capital Holdings Limited is a global enterprise dedicated to providing
diversified specialty insurance and reinsurance products to corporations,
public entities, and property and casualty insurers. Visit Alterra on the web
at www.alterracap.com.

INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS

This release includes statements about future economic performance, finances,
expectations, plans and prospects of Alterra and Markel, both individually and
on a combined basis, that are forward-looking statements for purposes of the
safe harbor provisions of the Private Securities Litigation Reform Act of
1995. There are risks and uncertainties that could cause actual results to
differ materially from those expressed in or suggested by such statements. For
further information regarding factors affecting future results of Alterra and
Markel, please refer to their respective Annual Report on Form 10-K for the
year ended December 31, 2011 and Quarterly Reports on Form 10-Q and other
documents filed by Alterra and Markel since March 1, 2012 with the Securities
Exchange Commission (“SEC”). These documents are also available free of
charge, in the case of Alterra, by directing a request to Alterra through Joe
Roberts, Chief Financial Officer, or Susan Spivak Bernstein, Senior Vice
President, Investor Relations, at 441-295-8800 and, in the case of Markel, by
directing a request to Bruce Kay, Investor Relations, at 804-747-0136. Neither
Alterra nor Markel undertakes any obligation to update or revise publicly any
forward-looking statement whether as a result of new information, future
developments or otherwise.

This release contains certain forward-looking statements within the meaning of
the U.S. federal securities laws. Statements that are not historical facts,
including statements about Alterra’s and Markel’s beliefs, plans or
expectations, are forward-looking statements. These statements are based on
Alterra’s or Markel’s current plans, estimates and expectations. Some
forward-looking statements may be identified by use of terms such as
“believe,” “anticipate,” “intend,” “expect,” “project,” “plan,” “may,”
“should,” “could,” “will,” “estimate,” “predict,” “potential,” “continue,” and
similar words, terms or statements of a future or forward-looking nature. In
light of the inherent risks and uncertainties in all forward-looking
statements, the inclusion of such statements in this release should not be
considered as a representation by Alterra, Markel or any other person that
Alterra’s or Markel’s objectives or plans, both individually and on a combined
basis, will be achieved. A non-exclusive list of important factors that could
cause actual results to differ materially from those in such forward-looking
statements includes the following: (a) the occurrence of natural or man-made
catastrophic events with a frequency or severity exceeding expectations; (b)
the adequacy of loss reserves and the need to adjust such reserves as claims
develop over time; (c) the failure of any of the loss limitation methods the
parties employ; (d) any adverse change in financial ratings of either company
or their subsidiaries; (e) the effect of competition on market trends and
pricing; (f) cyclical trends, including with respect to demand and pricing in
the insurance and reinsurance markets; (g) changes in general economic
conditions, including changes in interest rates and/or equity values in the
United States of America and elsewhere; and (h) other factors set forth in
Alterra’s and Markel’s recent reports on Form 10-K, Form 10-Q and other
documents filed with the SEC by Alterra and Markel.

Risks and uncertainties relating to the proposed transaction include the risks
that: (1) the parties will not obtain the requisite shareholder or regulatory
approvals for the transaction; (2) the anticipated benefits of the transaction
will not be realized or the parties may experience difficulties in
successfully integrating the two companies; (3) the parties may not be able to
retain key personnel; (4) the conditions to the closing of the proposed merger
may not be satisfied or waived; (5) the outcome of any legal proceedings to
the extent initiated against Alterra or Markel or its respective directors and
officers following the announcement of the proposed merger is uncertain; (6)
the acquisition may involve unexpected costs; and (7) the businesses may
suffer as a result of uncertainty surrounding the acquisition. These risks, as
well as other risks of the combined company and its subsidiaries may be
different from what the companies expect, or have previously experienced, and
each party’s management may respond differently to any of the aforementioned
factors. These risks, as well as other risks associated with the merger, will
be more fully discussed in the joint proxy statement/prospectus that will be
included in the Registration Statement on Form S-4 to be filed by Alterra and
Markel with the SEC. Readers are cautioned not to place undue reliance on any
forward-looking statements, which speak only as of the date on which they are
made.

ADDITIONAL INFORMATION ABOUT THE PROPOSED MERGER AND WHERE TO FIND IT:

This release relates to a proposed transaction between Alterra and Markel that
will become the subject of a registration statement, which will include a
joint proxy statement/prospectus, to be filed by Alterra and Markel with the
SEC. This material is not a substitute for the joint proxy
statement/prospectus that Alterra and Markel will file with the SEC or any
other document that Alterra or Markel may file with the SEC or Alterra or
Markel may send to its shareholders in connection with the proposed
transaction. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE JOINT PROXY
STATEMENT/PROSPECTUS AND ALL OTHER RELEVANT DOCUMENTS THAT MAY BE FILED WITH
THE SEC OR SENT TO SHAREHOLDERS, INCLUDING THE DEFINITIVE JOINT PROXY
STATEMENT/PROSPECTUS THAT WILL BE PART OF THE REGISTRATION STATEMENT ON FORM
S-4, AS THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION
ABOUT THE PROPOSED MERGER. All documents, when filed, will be available free
of charge at the SEC’s website (www.sec.gov) or, in the case of Alterra, by
directing a request to Joe Roberts, Chief Financial Officer, or Susan Spivak
Bernstein, Senior Vice President, Investor Relations, at 441-295-8800 and, in
the case of Markel, by directing a request to Bruce Kay, Investor Relations,
at 804-747-0136].

Contact:

Markel Corporation
Bruce Kay, 1-804-747-0136
bkay@markelcorp.com
or
Alterra Capital Holdings Limited
Susan Spivak Bernstein, 1-212-898-6640
Senior Vice President
susan.spivak@alterra-bm.com
or
Kekst and Company
Peter Hill, 1-212-521-4800
peter-hill@kekst.com