425 1 d233443d425.htm FORM 425 Form 425

Filed by Exelon Corporation

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12 of the Securities Exchange Act of 1934

Subject Company: Constellation Energy Group, Inc.

(Reg. No. 333-175162)

On September 20, 2011, Exelon began to use the following slides concerning the proposed merger and other information in a series of meetings with investors:

Bank of America Merrill Lynch
2011
Power and
Gas Leaders
Conference
Christopher
M
Crane
–
President
and
COO,
Exelon
Corp.
September 20, 2011

Cautionary Statements Regarding
Forward-Looking Information
2
Except for the historical information contained herein, certain of the matters discussed in this communication constitute
“forward-looking statements” within the meaning of the Securities Act of 1933 and the Securities Exchange Act of 1934,
both as amended by the Private Securities Litigation Reform Act of 1995. Words such as “may,” “will,” “anticipate,”
“estimate,” “expect,” “project,” “intend,” “plan,” “believe,” “target,” “forecast,” and words and terms of similar substance
used in connection with any discussion of future plans, actions, or events identify forward-looking statements. These
forward-looking statements include, but are not limited to, statements regarding benefits of the proposed merger of
Exelon Corporation (Exelon) and Constellation Energy Group, Inc. (Constellation), integration plans and expected
synergies, the expected timing of completion of the transaction, anticipated future financial and operating performance
and results, including estimates for growth. These statements are based on the current expectations of management of
Exelon and Constellation, as applicable. There are a number of risks and uncertainties that could cause actual results to
differ materially from the forward-looking statements included in this communication regarding the proposed merger. For
example, (1) the companies may be unable to obtain shareholder approvals required for the merger; (2) the companies
may be unable to obtain regulatory approvals required for the merger, or required regulatory approvals may delay the
merger or result in the imposition of conditions that could have a material adverse effect on the combined company or
cause the companies to abandon the merger; (3) conditions to the closing of the merger may not be satisfied; (4) an
unsolicited offer of another company to acquire assets or capital stock of Exelon or Constellation could interfere with the
merger; (5) problems may arise in successfully integrating the businesses of the companies, which may result in the
combined company not operating as effectively and efficiently as expected; (6) the combined company may be unable to
achieve cost-cutting synergies or it may take longer than expected to achieve those synergies; (7) the merger may
involve unexpected costs, unexpected liabilities or unexpected delays, or the effects of purchase accounting may be
different from the companies’ expectations; (8) the credit ratings of the combined company or its subsidiaries may be
different from what the companies expect; (9) the businesses of the companies may suffer as a result of uncertainty
surrounding the merger; (10) the companies may not realize the values expected to be obtained for properties expected
or required to be divested; (11) the industry may be subject to future regulatory or legislative actions that could adversely
affect the companies; and (12) the companies may be adversely affected by other economic, business, and/or
competitive factors. Other unknown or unpredictable factors could also have material adverse effects on future results,
performance or achievements of Exelon, Constellation or the combined company.

Cautionary Statements Regarding
Forward-Looking Information (Continued)
3
Discussions of some of these other important factors and assumptions are contained in Exelon’s and Constellation’s
respective filings with the Securities and Exchange Commission (SEC), and available at the SEC’s website at
www.sec.gov, including: (1)  Exelon’s 2010 Annual Report on Form 10-K in (a) ITEM 1A. Risk Factors, (b) ITEM 7.
Management’s Discussion and Analysis of Financial Condition and Results of Operations and (c) ITEM 8. Financial
Statements and Supplementary Data: Note 18; (2)  Exelon’s Quarterly Report on Form 10-Q for the quarterly period
ended June 30, 2011 in (a) Part II, Other Information, ITEM 1A. Risk Factors, (b) Part 1, Financial Information, ITEM 2.
Management’s Discussion and Analysis of Financial Condition and Results of Operations and (c) Part I, Financial
Information, ITEM 1. Financial Statements: Note 13; (3)  Constellation’s 2010 Annual Report on Form 10-K in (a) ITEM
1A. Risk Factors, (b) ITEM 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations
and (c) ITEM 8. Financial Statements and Supplementary Data: Note 12; and (4) Constellation’s Quarterly Report on
Form 10-Q for the quarterly period ended June 30, 2011 in (a) Part II, Other Information, ITEM 1A. Risk Factors and
ITEM 5. Other Information, (b) Part I, Financial Information, ITEM 2. Management’s Discussion and Analysis of Financial
Condition and Results of Operations and (c) Part I, Financial Information, ITEM 1. Financial Statements: Notes to
Consolidated Financial Statements, Commitments and Contingencies. These risks, as well as other risks associated with
the proposed merger, are more fully discussed in the preliminary joint proxy statement/prospectus included in
Amendment No. 1 to the Registration Statement on Form S-4 that Exelon filed with the SEC on August 17, 2011 in
connection with the proposed merger.  In light of these risks, uncertainties, assumptions and factors, the forward-looking
events discussed in this communication may not occur. Readers are cautioned not to place undue reliance on these
forward-looking statements, which speak only as of the date of this communication. Neither Exelon nor Constellation
undertake any obligation to publicly release any revision to its forward-looking statements to reflect events or
circumstances after the date of this communication. 
Additional Information and Where to Find It
This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities, or a solicitation
of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale
would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.  On August 17,
2011, Exelon filed with the SEC Amendment No. 1 to its Registration Statement on Form S-4 that included a preliminary
joint proxy statement/prospectus and other relevant documents to be mailed by Exelon and Constellation to their
respective security holders in connection with the proposed merger of Exelon and Constellation.

Additional Information and Where to Find It
4
These materials are not yet final and may be amended.  WE URGE INVESTORS AND SECURITY HOLDERS TO READ
THE PRELIMINARY JOINT PROXY STATEMENT/PROSPECTUS AND THE DEFINITIVE JOINT PROXY
STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS WHEN THEY BECOME AVAILABLE,
BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION about Exelon, Constellation and the
proposed merger.  Investors and security holders will be able to obtain these materials (when they are available) and
other documents filed with the SEC free of charge at the SEC's website, www.sec.gov.  In addition, a copy of the
preliminary joint proxy statement/prospectus and definitive joint proxy statement/prospectus (when it becomes available)
may be obtained free of charge from Exelon Corporation, Investor Relations, 10 South Dearborn Street, P.O. Box 805398,
Chicago, Illinois 60680-5398, or from Constellation Energy Group, Inc., Investor Relations, 100 Constellation Way, Suite
600C, Baltimore, MD 21202. Investors and security holders may also read and copy any reports, statements and other
information filed by Exelon, or Constellation, with the SEC, at the SEC public reference room at 100 F Street, N.E.,
Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 or visit the SEC’s website for further information on its
public reference room.
 
Participants in the Merger Solicitation 
Exelon, Constellation, and their respective directors, executive officers and certain other members of management and
employees may be deemed to be participants in the solicitation of proxies in respect of the proposed transaction.
Information regarding Exelon’s directors and executive officers is available in its proxy statement filed with the SEC by
Exelon on March 24, 2011 in connection with its 2011 annual meeting of shareholders, and information regarding
Constellation’s directors and executive officers is available in its proxy statement filed with the SEC by Constellation on
April 15, 2011 in connection with its 2011 annual meeting of shareholders. Other information regarding the participants in
the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, is contained
in the preliminary joint proxy statement/prospectus and will be contained in the definitive joint proxy statement/prospectus.

Creating Value Through a Strategic Merger
Delivers financial benefits to both sets of shareholders
Increases scale and scope of the business across the value chain
Matches the industry’s premier clean merchant generating fleet with the
leading retail and wholesale customer platform
Diversifies the generation portfolio
Continued upside to power market recovery
Maintains a strong regulated earnings profile with large urban utilities
Successful integration experience from prior mergers and acquisitions
Combining Exelon’s generation fleet and Constellation’s customer-facing
businesses creates a strong platform for growth and delivers benefits to
investors and customers
5

Combination Will Result in Enhanced Scale,
Scope, Flexibility and Financial Strength
•
$8 billion
•
$11 billion
•
11,980 (Total)
•
1,921 (Nuclear)
•
1.2 mil. (MD) 
•
0.7 mil. (MD)
•
44 states & D.C.
(5)
•
~110 TWh/yr
•
29% Generation
•
44% Utility
•
27% NewEnergy
Pro forma
Standalone
Owned
Generation
(in
MW)
(2)
Regulated
Utilities
Competitive
Retail &
Wholesale
(4)
Business
Mix
(6)
•
$28 billion
•
$41 billion
•
26,339 (Total)
•
17,047 (Nuclear)
Electric customers
•
5.4 mil. (IL, PA)
Gas customers
•
0.5 mil. (PA)
•
4 states
•
~59
TWh/yr
2011 EBITDA
•
61% Generation
•
39% Utilities
•
$35 billion
•
$52 billion
•
44 states & D.C.
(5)
•
~169
TWh energy sales
•
Expect >50% pro forma EBITDA
from competitive business
•
35,671 (Total)
(3)
•
18,968 (Nuclear)
•
6.6 million electric & gas customers
in IL, PA and MD
Note: Data as of 12/31/10 unless stated otherwise.
(1)  Market Value as of 9/14/11. Enterprise Value represents Market Value plus Net Debt as of 6/30/11.
(2)  Exelon data includes 720 MW for Wolf Hollow. Constellation data includes 2,950 MW for Boston Generation assets.
(3)  Net of physical market mitigation assumed to be 2,648 MW.
(4)  TWh/yr represents 2011 booked electric sales as of 12/31/2010. Exelon load includes ComEd swap. Data also includes 2011 partial year
estimated electric sales from StarTex and MXEnergy (acquired by Constellation).
(5)  Competitive and wholesale business also active in Alberta, British Columbia and Ontario, Canada.
(6)  Exelon EBITDA estimates per equity research. Constellation EBITDA estimates per company guidance from Q1 2011.
6
Enterprise
Value
(1)
Market  Value and

On Track for Merger Close in Early Q1 2012
2012
Q3
Q4
Q1
Approvals
Shareholder vote
SEC
NRC
Texas PUCT
FERC
DOJ
NY PSC
MD PSC
7
Regulatory
proceedings
are
progressing
well
and
we
are
on
track
to
close
in
early Q1, 2012
2011
Shareholder vote
1/5/12
Decision deadline
Secured approval from Texas
Proxy mailing
SEC has completed its
review of S-4
Expect approval in Q4
Filed merger approval application related filings on
May 20, 2011
Filed for approval with the Maryland  PSC on May 25, 2011
Filed for indirect transfer of Constellation Energy licenses on
May 12, 2011
Submitted HSR filing on May 31, 2011 for review under U.S. antitrust laws

Portfolio Matches Generation with Load in
Key Competitive Markets
MISO (TWh)
PJM (TWh)
South
(1)
(TWh)
ISO-NE & NY ISO
(2)
(TWh)
West (TWh)
The combination establishes an industry-leading platform with regional
diversification of the generation fleet
(1)
Represents load and generation in ERCOT, SERC and SPP.
(2)
Constellation load includes ~0.7TWh of load served in Ontario.
31.8
147.3
Load
102.1
43.4
58.7
Generation
179.1
Constellation
Exelon
Load
6.3
5.8
0.5
Generation
9.1
9.1
29.5
Load
Generation
14.2
4.8
9.4
2.4
Load
Generation
0.8
0.4
0.4
28.5
23.2
Load
Generation
8
Exelon load includes ComEd Swap, load sold through affiliates, fixed and indexed load sales and load sold through POLR auctions.
Constellation load includes load sold through affiliates, fixed and indexed load sales and load sold through POLR auctions. 
Note:
Data
for
Exelon
and
Constellation
represents
expected
generation
(owned
and
contracted)
and
booked
electric
sales
for
2011
as
of
12/31/10.  This data also includes 2011 partial year generation from Wolf Hollow (acquired by Exelon). Data also includes 2011 partial year
estimated electric sales from StarTex and MXEnergy (acquired by Constellation).

A Clean Generation Profile Creates Long-
Term Value in Competitive Markets
(1)
Exelon
generation
includes
Wolf
Hollow
acquisition
(720
MW
of
natural
gas).
Constellation
generation
includes
Boston
Generation
acquisition
(2,950
MW
of
natural gas). Constellation nuclear reflects 50.01% interest in Constellation Energy Nuclear Group LLC. Generation capacity doesn’t reflect contracted
capacity.
(2)
Net of physical market mitigation assumed to be 2,648 MW.
Exelon Standalone
(1)
Total Generation: 26,339 MW
Constellation Standalone
(1)
Total Generation: 11,980 MW
Pro forma Company (Net of Mitigation)
(2)
Total Generation: 35,671 MW
7%
Hydro
6%
Wind/Solar/Other
3%
Gas
13%
Oil
Coal
5%
Nuclear
65%
Wind/Solar/Other
Hydro
Oil
Gas
54%
Coal
23%
Nuclear
16%
3%
2%
2%
6%
Wind/Solar/Other
3%
Hydro
5%
Oil
Gas
27%
Coal
6%
Nuclear
53%
9
Combined company remains the premier low-cost generator

Merger Approvals Process on Schedule    
(as of 9/15/11)
10
Stakeholder
Status of Key Milestones
Filed
Approved
Securities and Exchange
Commission (SEC)
(File No. 333-175162)
•
SEC has completed its review of the amended S-4 
Registration Statement
•
Shareholder approval anticipated in mid November  2011
Department of Justice
(DOJ)
•
Submitted Hart-Scott-Rodino filing on May 31, 2011 for
review under U.S. antitrust laws
•
Approval expected by January 2012
Federal Energy Regulatory
Commission (FERC)
(Docket No. EC 11-83)
•
Filed merger approval application and related filings on
May 20, 2011, which assesses market power-related
issues
•
Approval expected in Q4 2011
Nuclear Regulatory
Commission
(Docket Nos. 50-317, 50-318, 50-220,
50-410, 50-244, 72
-8, 72-67)
•
Filed for indirect transfer of Constellation Energy licenses
on May 12, 2011
•
Approval expected by January 2012
Maryland PSC
(Case No. 9271)
•
Filed for approval with the Maryland Public Service
Commission on May 25, 2011
•
Approval expected by January 5, 2012
New York PSC
(Case No. 11-E-0245)
•
Filed for approval with the New York State Public Service
Commission on May 17, 2011
•
Approval expected in Q4 2011
Texas PUC
(Case No. 39413)
•
Filed for approval with the Public Utility Commission of
Texas on May 17, 2011
•
Approval received on  August 3, 2011

Maryland PSC Review Schedule
* Initial
intervenor
testimony
with
respect
to
market
power
is
due
on
September
23
rd
for
all
parties except for the Independent Market Monitor, and rebuttal testimony with respect to
market
power
is
due
on
October
17
th
.
11
Significant Events
Date of Event
•
Filing of Application
May 25, 2011
•
Intervention Deadline
June 24, 2011
•
Prehearing Conference
June 28, 2011
•
Filing of Staff, Office of People Counsel and Intervenor Testimony
September 16, 2011*
•
Filing of Rebuttal Testimony
October 12, 2011*
•
Filing of Surrebuttal Testimony
October 26, 2011
•
Status Conference
October 28, 2011
•
Evidentiary Hearings
October 31, 2011 -
November 10, 2011
•
Public Comment Hearings
November 29, December 1 &
December 5, 2011
•
Filing of Initial Briefs
December 1, 2011
•
Filing of Reply Briefs
December 15, 2011
•
Decision Deadline
January 5, 2012