Pershing Square Publicly Releases Letter to Regulators and Open Source Model Regarding...

Pershing Square Publicly Releases Letter to Regulators and Open Source Model
Regarding MBIA Inc. and Ambac Financial Group Inc.

NEW YORK, Jan. 31 /PRNewswire/ -- Pershing Square Capital Management, L.P.
announced today that it has made publicly available a letter sent yesterday to
state and federal regulatory authorities. The letter introduces a new Open
Source Research project initiated by Pershing Square. The Open Source
Research project includes the release of version 1.0 of an Open Source Model,
a dynamic financial model that contains extensive detail on the CDO and
related exposures of the insurance operating subsidiaries of both MBIA Inc.
and Ambac Financial Group Inc. Since its initial release yesterday afternoon,
users have initiated over 2000 downloads of the Open Source Model.
The Open Source Model can be customized to allow users to estimate MBIA's
and Ambac's losses using their own assumptions. The detailed methodologies
and assumptions underlying the Open Source Model are also included in the
materials made publicly available. The materials can be found on the Internet
at:
http://www.yousendit.com/download/Mmd0UXVuQzMzeUxIRGc9PQ
By focusing the discussion on a fundamental, data-driven approach,
Pershing Square expects that the dissemination of the Open Source Model will
enable market participants and regulators to more accurately estimate probable
losses by relying on rigorous fundamental analyses of specific credit
exposures. Pershing Square encourages all market participants to use the Open
Source Model as a tool to arrive at their own conclusions and report their
findings to the market to further improve the process of evaluating the risk
of loss in the bond insurance industry.
Access to the Open Source Model is subject to certain disclaimers and
conditions of use, all of which are included in the materials posted on the
Internet.
About Pershing Square Capital Management, L.P.
Pershing Square Capital Management, L.P. is a registered investment
advisor with the Securities and Exchange Commission that focuses on mid-cap
and large-cap public investments. Pershing Square manages certain investment
funds that are in the business of trading -- buying and selling -- securities
and credit default swaps. While Pershing Square currently maintains a net
short position in MBIA Inc. and Ambac Financial Group Inc. and may have other
positions in the industry, Pershing Square may change its position regarding
the companies and possibly increase, decrease, dispose of, or change the form
of its investment in the companies for any or no reason.
SOURCE Pershing Square Capital Management, L.P.

William A. Ackman of Pershing Square Capital Management, L.P.,
+1-212-813-3700