NiSource Announces Results to Date for Its Cash Tender Offers, Extends Early Tender Premium to Expiration Date

MERRILLVILLE, Ind., Nov. 22, 2011 /PRNewswire/ — NiSource Inc. (NYSE: NI)
announced today that, pursuant to the previously announced cash tender offers of
its finance subsidiary, NiSource Finance Corp., approximately $125 million
aggregate principal amount of its outstanding 10.75% Notes due 2016 (“2016
Notes”) and approximately $228 million aggregate principal amount of its
outstanding 6.15% Notes due 2013 (“2013 Notes”) were validly tendered and not
validly withdrawn before 5:00 p.m., New York City time, today (the “Early
Participation Date”), according to information provided by Global Bondholder
Services Corporation, the depositary for the tender offers.

NiSource Finance has extended the deadline by which holders who tender their
2016 Notes and 2013 Notes will be eligible to receive the early tender payment
until 11:59 p.m., New York City time, on December 12, 2011 (the “Expiration
Date”), unless further extended by NiSource Finance. However, withdrawal rights
for 2016 Notes and 2013 Notes tendered in the tender offers have not been
extended and therefore expired at 5:00 p.m., New York City time, on November 22,
2011. Tenders submitted after that time are irrevocable except in the limited
circumstances where additional withdrawal rights are required by law. The tender
offers are made pursuant to an Offer to Purchase, dated November 14, 2011 and
related Letter of Transmittal dated November 14, 2011, which set forth a
comprehensive description of the terms of the offers.

The total consideration to be received for each $1,000 principal amount of Notes
validly tendered and not withdrawn in the tender offers before the Expiration
Date and accepted for purchase will be determined in the manner described in the
Offer to Purchase by reference to the fixed spread over the yield to maturity of
the applicable U.S. Treasury Security specified for the particular series of
Notes on the cover page of the Offer to Purchase. The purchase price for each
series of Notes will be determined based on certain quotes for the reference
Treasury Securities available at 10:00 a.m., New York City time, on November 23,
2011. The purchase price for each series of Notes will include an early tender
payment of $30 per $1,000 principal amount and accrued and unpaid interest up
to, but not including, the applicable settlement date. NiSource Finance may
elect an early settlement option, which is described in the Offer to Purchase,
with respect to the 2016 Notes.

The tender offers are scheduled to expire at 11:59 p.m., New York City time, on
the Expiration Date, unless extended or earlier terminated. NiSource Finance
will accept for purchase all validly tendered 2016 Notes that are not validly
withdrawn. NiSource Finance will accept for purchase, on a pro rata basis, 2013
Notes in an amount equal to the difference between $250 million and the
principal amount of 2016 Notes validly tendered and accepted for purchase. The
tender offers are subject to the satisfaction or waiver of certain conditions
set forth in the Offer to Purchase, including a financing condition which is
expected to be satisfied upon the closing of NiSource Finance’s sale of $500
million aggregate principal amount of two series of its long-term debt
securities, which is scheduled for November 23, 2011.

Questions regarding the tender offer may be directed to the Dealer Manager,
Citigroup Global Markets Inc. at (212) 723-6106 (collect) or (800) 558-3745
(toll-free). Requests for documents may be directed to Global Bondholder
Services Corporation, the information agent and depositary for the tender offer,
at (212) 430-3774 (for banks and brokers) or (866) 952-2200 (toll-free).

This news release is for informational purposes only and does not constitute an
offer to purchase or a solicitation of an offer to sell with respect to the 2016
Notes or the 2013 Notes, nor is this news release an offer to sell, a
solicitation to buy or an offer to purchase or sell any securities. The tender
offer is being made only pursuant to the Offer to Purchase and only in such
jurisdictions as is permitted under applicable law.

About NiSource

NiSource Inc. (NYSE: NI), based in Merrillville, Ind., is a Fortune 500 company
engaged in natural gas transmission, storage and distribution, as well as
electric generation, transmission and distribution. NiSource operating companies
deliver energy to 3.7 million customers located within the high-demand energy
corridor stretching from the Gulf Coast through the Midwest to New England.
Together, NiSource’s gas transmission and storage companies operate a
15,000-mile network of natural gas pipelines, 37 storage fields and serve some
of the nation’s largest and fastest-growing energy markets in the Northeast,
Midwest and Mid-Atlantic regions. Information about NiSource and its
subsidiaries is available via the Internet at www.nisource.com. NI-F

Forward-Looking Statements

This news release includes forward-looking statements within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. Those statements include statements
regarding the intent, belief or current expectations of NiSource and its
management. Although NiSource believes that its expectations are based on
reasonable assumptions, it can give no assurance that its goals will be
achieved. Readers are cautioned that the forward-looking statements in this news
release are not guarantees of future performance and involve a number of risks
and uncertainties, and that actual results could differ materially from those
indicated by such forward-looking statements. Important factors that could cause
actual results to differ materially from those indicated by such forward-looking
statements include, but are not limited to, the following: weather; fluctuations
in supply and demand for energy commodities; growth opportunities for NiSource’s
businesses; increased competition in deregulated energy markets; the success of
regulatory and commercial initiatives; dealings with third parties over whom
NiSource has no control; actual operating experience of NiSource’s assets; the
regulatory process; regulatory and legislative changes; the impact of potential
new environmental laws or regulations; the results of material litigation;
changes in pension funding requirements; changes in general economic, capital
and commodity market conditions; and counter-party credit risk, and the matters
set forth in the “Risk Factors” section in NiSource’s 2010 Form 10-K and 2011
Forms 10-Q, many of which risks are beyond the control of NiSource. NiSource
expressly disclaims a duty to update any of the forward-looking statements
contained in this release.