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 November 7, 2011, Exelon began to use the following slides concerning the proposed merger and other information with investors at the Edison Electric Institute Financial Conference:

Exelon and Constellation Energy: Merger and Company Update

Edison Electric Institute Financial Conference

November 7-8, 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 September 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 definitive joint proxy statement/prospectus included in the Registration Statement on Form S-4 that Exelon filed with the SEC

and that the SEC declared effective on October 11, 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

In connection with the proposed merger between Exelon and Constellation, Exelon filed with the SEC a Registration Statement on

Form S-4 that included the definitive joint proxy statement/prospectus. The Registration Statement was declared effective by the

SEC on October 11, 2011. Exelon and Constellation mailed the definitive joint proxy statement/prospectus to their respective security

holders on or about October 12, 2011. WE URGE INVESTORS AND SECURITY HOLDERS TO READ THE DEFINITIVE JOINT

PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, BECAUSE THEY

CONTAIN IMPORTANT INFORMATION about Exelon, Constellation and the proposed merger. Investors and security holders may

obtain copies of all documents filed with the SEC free of charge at the SEC's website, www.sec.gov. In addition, a copy of the

definitive joint proxy statement/prospectus 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.

4

Compelling Merger Rationale

Creates the leading competitive energy

provider in the U.S.

Matches Exelon’s clean generation fleet

with Constellation’s customer-facing

leading retail and wholesale platform

Creates economies of scale through

expansion across the value chain

Strategic Benefits

Financial Benefits

Diversifies generation portfolio across 

regions

Adds clean generation to the portfolio

Enhances margins in the competitive

portfolio

Competitive Portfolio

Earnings and cash flow accretive

Dividend uplift for Constellation

shareholders

Continued upside to power market

recovery

Strong balance sheet for combined

company

Utility Benefits

Maintains a regulated earnings profile

with three large urban utilities

Enables operational enhancements

from sharing of best practices across

utilities

Transaction creates incremental strategic and financial value

aligned with both companies’

existing goals

5

Merger Appeals to Key Stakeholders and Governments 

(1)  Based on the 30-day average Exelon and Constellation closing stock prices as of April 26, 2011.

Stakeholder

Commitments & Benefits

Customers

$100 one

-time credit for BGE residential customers

Direct benefit from merger synergies at the utilities

Opportunities for operational improvements through sharing of

utilities’

best practices

$15 million for various programs with direct benefits to BGE

customers

Investors

Upfront premium of 18.5%

(1)

to CEG shareholders

Dividend accretion of 103% post-close for CEG shareholders

EPS accretion of >5% in 2013

Earnings upside to power market recovery

Strong credit profile maintained for combined company

State of Maryland and City

of Baltimore

Maintains a large employee presence and platform for growth

in Maryland

New LEED-certified headquarters for wholesale, retail and

renewable energy development business in Baltimore

BGE to maintain independent operations and remain

headquartered in Baltimore

25 MWs of renewable energy development in MD

$4 million to support EmPower Maryland Energy Efficiency Act

Charitable contributions maintained at current levels for at

least 10 years after the merger closes

6

Enhanced Maryland Proposal

Our additional commitments address a number of key stakeholder concerns

Intervenor Concerns

Key Exelon/Constellation Additional Commitments

Additional Customer

Benefits

Added flexibility for Maryland PSC to determine use of $15 million offered for

programs directly benefiting BGE customers

Ring-Fencing

No corporate reorganization under certain defined circumstances relating to RF

HoldCo, BGE or Exelon Energy Delivery Company without prior Commission approval

Obtain a new non-consolidation opinion to ensure the effectiveness of BGE ring-

fencing

No requests for modification of BGE ring-fencing for 3 years

Financial

Regular reporting on credit ratings and metrics of BGE to Maryland PSC

Specific commitments regarding the level of BGE capital and O&M expenditures in

2012 and 2013

Report comparative pre-

and post-merger shared services costs to PSC

Corporate Governance

BGE’s CEO will be a member of Exelon Management’s Executive Committee

Executive Committee will meet periodically in Baltimore

Service and Operation

Commitment to meet existing BGE supplier diversity requirements

Provide assessment of BGE CAIDI (outage duration) performance within 12 months

after the merger closes

Market Power

In

addition

to

2,648

MW

of

identified

plant

divestitures,

comply

with

settlement

terms

with PJM Market Monitor restricting buyers of divested plants and imposing other

behavioral commitments

7

Strong Proposal to Address Market Power

The companies have offered a comprehensive, robust mitigation package

C.P. Crane   

399 MW

Brandon Shores 

1,273 MW

H.A. Wagner      

976 MW

Note:

Assets

to

be

divested

–

Brandon

Shores

(Coal),

H.A.

Wagner

(Coal/Oil/Gas)

and

C.P.

Crane

(Oil/Coal).

Analyzed market power considerations and proposed

mitigation plan to address market concentration

concerns

Proposed comprehensive mitigation plan to address

market concentration in PJM in initial application,

including:

•

Physical sale of 3 baseload generation facilities

totaling 2,648 MW

•

Additional sale of 500 MW via contracts to

mitigate temporary market power issues

Filed with FERC and Maryland PSC on October 11,

2011

No change to assets identified in original proposal

Additional commitment not to sell plants to certain

identified PJM generators

Additional assurances on how we will bid units in PJM

energy and capacity markets

Future retirement of units will be conditioned on meeting

specified requirements

Proactive

divestiture

proposal

Settlement with

PJM

Independent 

Market Monitor

(IMM)

8

Note: Data as of 9/30/11.  Exelon solar addition MW based on alternating current (AC); Constellation solar additions (in MW) based on direct

current (DC).

(1)    Generation capacity net of physical market mitigation assumed to be 2,648 MW consisting of Brandon Shores (1,273 MW), H.A. Wagner

(976 MW) and C.P. Crane (399 MW).

(2)    Electric load includes all booked 2011E competitive retail and wholesale sales, including index products. Exelon load does not include the

ComEd swap (~26 TWh). Gas load includes all booked and forecasted 2011E competitive retail sales as of 9/30/11.

Reserves (gas)

266 bcf

Owned Generating

Capacity

35 GWs

(1)

Electric

Transmission

7,350 miles

Electric & Gas Dist.

6.6 million

customers

Retail &

Wholesale Volumes

(2)

(Electric & Gas)

~167 TWh, 372 bcf

Notable Generation Acquired or

Under Development in 2011

Exelon Additions

720 MW Wolf Hollow CCGT (TX)

230 MW Antelope Valley Solar Ranch

One (CA)

230 MW Michigan Wind Projects (MI)

Constellation Additions

2,950 MW Boston Generating gas

fleet

30.4 MW Sacramento Municipal Utility

District Solar (CA)

16.1 MW Maryland Generating Clean

Horizons Solar (MD)

7.8 MW Vineland Municipal Electric

Utility Solar (NJ)

5.4 MW Toys “R”

Us Solar (NJ)

5.2 MW Johnson Matthey, West

Deptford Solar (NJ)

5.0 MW U.S. State Department Solar

(NJ)

Transaction creates the largest –

and growing –

competitive energy

company in the U.S.

Scale, Scope and Flexibility Across the

Value Chain

Upstream

Downstream

Well Positioned for Evolving Regulatory Requirements

(1)

Total owned generation capacity as of 9/30/2011 for Exelon and Constellation, net of physical market mitigation

assumed to be 2,648 MW.

(2)

Coal capacity shown above includes Eddystone 2 (309 MW) to be retired on 6/1/2012.

(3)

Oil capacity shown above includes Cromby 2 (201 MW) to be retired on 12/31/2011.

(4)

Pending approval of owner group.

A clean and diverse portfolio that is well positioned for environmental

upside from EPA regulations

9

Total Generation Capacity

(1)

: 35,327 MW

5%

Wind/Solar/Other

3%

Gas

Hydro

Oil

(3)

Nuclear

54%

6%

Coal

(2)

5%

Cleanest large merchant generation

portfolio in the nation

Less than 5% of combined generation

capacity will require capital expenditures

to comply with Air Toxic rules

-

Approx. $200 million of CapEx, majority of

which is at Conemaugh

(4)

(Exelon and

Constellation ownership share ~31%)

Low-cost generation capacity provides

unparalleled leverage to rising commodity

prices 

Incremental 500 MW

of coal and oil

capacity to be retired by middle of next

year

Combined Company Portfolio

27%

10

Texas Generation Portfolio Is Well Suited to Serve Load

ERCOT Generation

Capacity –

MW

(1)

5,311

CEG Intermediate

1,839

EXC Intermediate

2,210

Exelon Peaking

1,262

(1)

Generation and capacity for Exelon and Constellation includes owned and contracted units, less any PPAs or tolls sold, as of

09/30/2011.

Exelon

wind

assets

in

Texas

(open

or

hedged)

are

not

included

in

the

capacity

shown

above.

Constellation

capacity

includes 517 MWs under a contract that expires in December 2011.

The combined generation portfolio will enhance the hedging capability for

managing load positions in Texas

Premium

Location

–

A

sizeable

generation

Hedging

Flexibility

–

Leverage

strong

asset

Strong

Asset

Mix

–

Intermediate

and

peaking

base and utilize market-based hedging

instruments to effectively manage load-

following obligations

position close to large load pockets in Dallas

and Houston

generation assets are effectively call options at

various heat rates that benefit from price

volatility

11

We will continue to use a well-defined hedging strategy to carefully

balance risk management and value creation

Increase the amount of generation

hedged over time, leaving some open

generation length

Exhibit flexibility in timing and type of

sales executed based on market

expectations

Select products and markets that

optimize the value of the generation

portfolio

Integrate hedging policy with financial

planning process to protect investment-

grade credit rating

Wholesale and Retail Businesses

Grow our generation to load strategy in multiple regions of the country by identifying

attractive investments and markets

Expand product offerings to customers in regions we serve

Growing the Portfolio

Growing the Portfolio

Hedging Program Characteristics

Hedging Program Characteristics

Transaction Maintains Solid Financial Position

Achievable Synergies

Annual

run rate

BGE

8%

ComEd & PECO

29%

Unregulated

Businesses

63%

Year 4

$310

Year 3

Year 2

Year 1

$200

Annual O&M Expense Savings

(1)

(in $MM)

12

Lower Liquidity Requirements

Existing liquidity

(ex-utilities)

Pro-forma liquidity

$10.3

Reduction in

existing liquidity

(in $B)

5-Year

Total

Synergies

Allocation

(2)

Maintaining

Strong

Investment

Grade

Ratings

(3)

Moody’s Credit

Ratings

S&P Credit

Ratings

Fitch Credit

Ratings

Exelon

Baa1

BBB-

BBB+

ComEd

Baa1

A-

BBB+

PECO

A1

A-

A

Generation

A3

BBB

BBB+

Constellation

Baa3

BBB-

BBB-

BGE

Baa2

BBB+

BBB+

$3-$4

-39%

$6.3

-

$7.3

Pro-Forma

$6.1

Exelon

$4.2

Constellation

Annual cost

savings of

$35M-$45M

(1) 

Before total costs to achieve of ~$650M primarily attributable to employee-related costs and transaction costs.

(2) 

Source: DeGregorio testimony filed with Maryland PSC on May 25, 2011.

(3) 

Ratings as of November 1, 2011.  Represents senior unsecured ratings of Exelon, Generation, Constellation and BGE and senior secured ratings for

ComEd and PECO.  S&P and Fitch affirmed all Exelon ratings upon announcement of merger. Moody’s affirmed  the ratings of ComEd and PECO and

placed the ratings of Exelon and Generation on review for downgrade. S&P and Moody’s placed Constellation on credit watch positive and 

affirmed BGE ratings.  Fitch affirmed Constellation and BGE ratings upon announcement.

13

Phased Approach to Designing the Future 

Our past experience with successful integration and our phased

approach to integrating Exelon and Constellation will enable the

realization of merger benefits

Success is defined by:

Closing the transaction in early 2012

Maintaining consistent and reliable operations

Capturing value and meeting synergy targets

Meeting commitments to stakeholders, regulators and governments

Acting as one to build an integrated enterprise that is positioned for

continued growth

August

–

December

Begins post-close

Completed  in August

Begins in November

Exelon & Constellation Energy Appendix

15

Merger Approvals Process on Schedule    

(as of 11/1/11)

Note: The Department of Public Utilities in Massachusetts concluded on September 26, 2011 that it does not have jurisdiction

over the merger.

Stakeholder

Status of Key Milestones

Approved

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

Securities and Exchange Commission

(SEC)

(File No. 333-175162)

Joint proxy statement declared effective on October 11, 2011

Shareholder Approval

Proxies mailed to shareholders of record at October 7, 2011

Shareholder meetings set for November 17, 2011

New York PSC

(Case No. 11–E–0245)

Filed with the New York Public Service Commission on  May 17, 2011

seeking a declaratory order confirming that a Commission review is not

required

Decision expected in Q4 2011

Department of Justice (DOJ)

antitrust laws and certified compliance with second request

Clearance 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

Settlement agreement filed with PJM Market Monitor on October 11, 2011

Order expected by November 16, 2011 (end of statutory period)

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

Order expected by January 2012

Maryland PSC

(Case No. 9271)

Filed for approval with the Maryland Public Service Commission on May 25,

2011

Evidentiary hearings begin October 31, 2011

Order expected by January 5, 2012

Submitted Hart-Scott-Rodino filing on

May 31, 2011 for review under U.S.

assesses market power-related issues

16

Maryland PSC Review Schedule (Case No. 9271)

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 18, 2011

Public Comment Hearings

November 29, December 1 &

December 5, 2011

Filing of Initial Briefs

December 5, 2011

Filing of Reply Briefs

December 19, 2011

Decision Deadline

January 5, 2012

* Initial

intervenor

testimony

with

respect

to

market

power

was

due

on

September

23  

for

all

parties

except

for

the

Independent

Market

Monitor

and

rebuttal

testimony

with

respect

to

market

power

was

due

on

October

17    .

rd

th

Portfolio Matches Generation with Load in

Key Competitive Markets

MISO (TWh)

PJM

(1)

(TWh)

South

(2)

(TWh)

ISO-NE & NY ISO

(3)

(TWh)

West

(4)

(TWh)

The combination establishes an industry-leading platform with regional

diversification of the generation fleet and customer-facing load business

Note: Data for Exelon and Constellation represents available expected generation (owned and contracted) and booked electric sales for 2011 as of 9/30/11. Expected

generation is adjusted for assets that have long term PPAs sold by Exelon or Constellation, including but not limited to wind and South assets. Exelon load doesn’t include

the ComEd swap (~26 TWh). Index load, which is a pass through load product with no price or volumetric risk to the seller, is not included in the load estimate.

(1)

Constellation

generation

includes

output

from

Brandon

Shores,

C.P.

Crane

and

H.A.

Wagner

(total

generation

~8.5

TWh).

(2)

Represents load and generation in ERCOT, SERC and SPP.

(3)

Constellation load includes ~0.7 TWh of load served in Ontario.

(4)

Constellation generation includes ~0.4 TWh of generation in Alberta.

Load

75.1

42.0

33.1

Generation

175.6

29.8

145.8

Constellation

Exelon

5.7

Load

5.1

0.6

Generation

8.6

8.6

18.5

Load

30.3

Generation

26.2

7.7

1.9

Load

Generation

0.6

Load

29.2

Generation

32.1

32.1

29.2

17

Manageable Debt Maturities

Debt

Maturity

Profile

(2012-2020)

EXC

EXC

EXC

Exelon

1,652

1,686

1,589

ExGen

PECO

ComEd

Exelon

BGE

Constellation

~70%

of

2012

–

2016

debt

maturities

consist

of

regulated

utility

debt

(in $M)

18

Weighted Average Cost of

Debt

(2)

Exelon

5.2%

ComEd

5.4%

PECO

5.5%

ExGen

5.5%

Constellation

6.2%

BGE

6.3%

152

552

74

552

(1)

2020

550

550

2019

602

600

2018

1,342

500

840

2017

1,261

702

516

41

2016

1,117

665

379

2015

260

800

75

2014

500

250

617

70

2013

1,020

300

252

467

2012

1,001

375

450

2

2

2

173

3

2

(1)

Debt maturity schedule and weighted average cost of debt as of 9/30/11.  Amounts do not include fair value swaps at Constellation. BGE

debt balances include annual transition bond payments from 2012 – 2017.

(2)

Weighted average cost of debt excludes any benefits for interest rate swaps. Utilities’ weighted average cost of debt includes debt

amortization costs. 

19

Exelon Dividend

Exelon’s Board of Directors approved a contingent stub dividend for Exelon shareholders of

$0.00571/share

per

day

for

Q1

2012

in

anticipation

of

the

merger

close

($0.525/share

for

the

quarter)

Stub dividend declaration ensures that Exelon shareholders continue to receive all dividends at the

current $2.10 per share annualized rate

Pre-

and post-close stub dividends must be declared separately to account for Constellation

shareholders becoming Exelon shareholders at merger close

Assuming

a

February

1,

2012

close

for

illustrative

purposes

only:

$0.525

Current Exelon shareholders will continue to receive a total dividend of

$0.525 per quarter

Record Date

Payment Date

Per Share

Amount

11/15/2011

12/09/2011

Regular Dividend

$0.525

1/31/2012

3/1/2012

Pre-close Stub Dividend

$0.440

2/15/2012

3/09/2012

Post-close Stub Dividend

$0.085

5/15/2012

6/09/2012

Regular Dividend

$0.525

(1)

(1)

(2)

(1)

Assuming a 2/1/2012 merger close; for Exelon shareholders, Q1 2012 dividend will be based on a per diem rate of $0.00571 ($0.525 divided by 92 days).

(2)

Future dividend, following the stub dividend, is subject to approval by the Board of Directors.

20

Constellation Dividend

Record Date

Payment Date

Per Share

Amount

12/12/2011

1/03/2012

Regular CEG Dividend

$0.24

1/31/2012

3/1/2012

Pre-close CEG Stub

Dividend

(1)

$0.132

2/15/2012

3/09/2012

Post-close EXC Stub

Dividend

(1)

$0.085

5/15/2012

6/09/2012

Regular

EXC

Dividend

(2)

$0.525

Constellation Energy’s Board of Directors approved a contingent stub dividend for Constellation

shareholders of $0.00264/share per day for Q1 2012 in anticipation of merger close

Stub dividend declaration ensures that Constellation shareholders continue to receive their existing

quarterly dividend rate prior to the merger, and benefit from the Exelon annualized dividend rate

($2.10 per share) beginning on the day the merger closes

Pre-

and post-close stub dividends must be declared separately to account for Constellation

shareholders becoming Exelon shareholders at merger close

Constellation shareholders will receive the Exelon dividend rate

upon

merger close

(1)

Assuming a 2/1/2012 merger close, Q1 2012 dividend will be based on a per diem rate of $0.00264 ($0.24 divided by 91 days).

Post-close  Exelon Q1 2012  stub dividend will be based on a per diem rate of $0.00571.

(2)

Assuming a 2/1/2012 merger close, Constellation shareholders will start receiving the full quarterly Exelon dividend of $0.525

per share in Q2 2012. Future dividend, following the stub dividend, is subject to approval by the Board of Directors.

Assuming

a

February

1,

2012

close

for

illustrative

purposes

only: