Constellation Energy Partners and PostRock Energy Enter Into Confidentiality Agreement

  Constellation Energy Partners and PostRock Energy Enter Into Confidentiality
  Agreement

Business Wire

HOUSTON -- June 6, 2013

Constellation Energy Partners LLC (NYSE MKT: CEP) today announced that the
company has entered into a confidentiality agreement with PostRock Energy
Corporation (NASDAQ: PSTR).

The confidentiality agreement covers discussions which may include a range of
strategic alternatives or potential transactions that could be pursued by the
companies. The parties intend to commence such confidential discussions
promptly. However, there can be no assurance that these discussions will
result in any transaction.

“With the sale of our Robinson’s Bend Field assets and refinancing now
complete we look to enhance unitholder value by increasing oil production from
our current asset base and pursuing accretive transactions to grow the
company,” said Stephen R. Brunner, President and Chief Executive Officer of
Constellation Energy Partners. "It makes sense for us to focus these efforts
on transactions that allow us to leverage our Mid-Continent footprint.”

PostRock and Section 203

PostRock Energy Corporation (“PostRock”) is engaged in the acquisition,
exploration, development, production and transportation of oil and natural
gas, primarily in the Cherokee Basin of Kansas and Oklahoma. PostRock, through
its subsidiary Constellation Energy Partners Management, LLC, currently owns
approximately 25.0% of the outstanding common units and all of the ClassA
units of Constellation Energy Partners LLC (“CEP”), which together represent a
26.5% interest in CEP.

CEP believes PostRock is an “interested unitholder” under Section203 of the
Delaware General Corporation Law (“Section 203”), which is applicable to CEP
pursuant to its limited liability company agreement. Section203, as it
applies to CEP, prohibits an interested unitholder, defined as a person who
owns 15% or more of the company’s outstanding common units, from engaging in
business combinations with CEP for three years following the time such person
becomes an interested unitholder without the approval of the company’s board
of managers and the vote of 66 2/3% of outstanding Class B common units,
excluding those held by the interested unitholder. Section203 broadly defines
“business combination” to encompass a wide variety of transactions with or
caused by an interested unitholder, including mergers, asset sales and other
transactions in which the interested unitholder receives a benefit on other
than a pro rata basis with other unitholders. CEP believes the "interested
unitholder" restrictions under Section203 that apply to PostRock expire in
December 2014.

Additional details concerning PostRock and Section 203 can be found in the
company’s filings with the Securities and Exchange Commission and on the
company’s Web site (http://www.constellationenergypartners.com).

About Constellation Energy Partners LLC

Constellation Energy Partners LLC is a limited liability company focused on
the acquisition, development and production of oil and natural gas properties,
as well as related midstream assets. The company’s proved reserves are located
in the Cherokee Basin in Oklahoma and Kansas, the Woodford Shale in the Arkoma
Basin in Oklahoma, and the Central Kansas Uplift in Kansas.

Forward-Looking Statements

This news release contains statements that are considered forward-looking
statements within the meaning of the Securities Act of 1933, as amended, and
the Securities Exchange Act of 1934, as amended. These forward-looking
statements are largely based on the companies’ expectations, which reflect
estimates and assumptions made by the companies’ management. These estimates
and assumptions reflect the companies’ best judgment based on currently known
market conditions and other factors. Although the companies believe such
estimates and assumptions to be reasonable, they are inherently uncertain and
involve a number of risks and uncertainties that are beyond the companies’
control. In addition, management's assumptions about future events may prove
to be inaccurate. Management cautions all readers that the forward-looking
statements contained in this news release are not guarantees of future
performance, and the reader cannot be assured that such statements will be
realized or the forward-looking events and circumstances will occur. Actual
results may differ materially from those anticipated or implied in the
forward-looking statements due to factors listed in the "Risk Factors" section
of each company’s SEC filings and elsewhere in those filings. All
forward-looking statements speak only as of the date of this news release. The
companies do not intend to publicly update or revise any forward-looking
statements as a result of new information, future events or otherwise. These
cautionary statements qualify all forward-looking statements attributable to
the companies or persons acting on the companies’ behalf.

Contact:

Constellation Energy Partners LLC
Investor Contact:
Charles C. Ward, (877) 847-0009
or
General Inquiries:
(877) 847-0008
www.constellationenergypartners.com