Filed by Old National Bancorp

Pursuant to Rule 425 under the Securities Act of 1933

Subject Company: Tower Financial Corporation

Commission File No.: 000-25287

Set forth below are slides from an investor presentation given on September 10, 2013 by Old National Bancorp regarding the proposed merger transaction between Old National Bancorp and Tower Financial Corporation.

Old National Bancorp To Acquire Tower Financial Corporation Combination of Two Banks Focused on Making Indiana Great! September 10, 2013

Lynell Walton Investor Relations Old National Bancorp

3 Additional Information for Shareholders In connection with the proposed merger, Old National Bancorp will file with the Securities and Exchange Commission (SEC) a Registration Statement on Form S-4 that will include a Proxy Statement of Tower Financial Corporation and a Prospectus of Old National Bancorp, as well as other relevant documents concerning the proposed transaction. Shareholders are urged to read the Registration Statement and the Proxy Statement/Prospectus regarding the merger when it becomes available and any other relevant documents filed with the SEC, as well as any amendments or supplements to those documents, because they will contain important information. A free copy of the Proxy Statement/Prospectus, as well as other filings containing information about Old National Bancorp and Tower Financial Corporation, may be obtained at the SEC’s Internet site (http://www.sec.gov). You will also be able to obtain these documents, free of charge, from Old National Bancorp at www.oldnational.com under the tab “Investor Relations” and then under the heading “Financial Information” or from Tower Financial Corporation by accessing Tower Financial Corporation’s website at www.towerbank.net under the tab “Investor Relations” and then under the heading “SEC Filings.” Old National Bancorp and Tower Financial Corporation and certain of their directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of Tower Financial Corporation in connection with the proposed merger. Information about the directors and executive officers of Old National Bancorp is set forth in the proxy statement for Old National’s 2013 annual meeting of shareholders, as filed with the SEC on a Schedule 14A on March 15, 2013. Information about the directors and executive officers of Tower Financial Corporation is set forth in the proxy statement for Tower Financial Corporation’s 2013 annual meeting of shareholders, as filed with the SEC on a Schedule 14A on March 28, 2013. Additional information regarding the interests of those participants and other persons who may be deemed participants in the transaction may be obtained by reading the Proxy Statement/Prospectus regarding the proposed merger when it becomes available. Free copies of this document may be obtained as described in the preceding paragraph.

4 Disclosures Forward Looking Statements   Non-GAAP Financial Measures This presentation contains certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995.  These statements include, but are not limited to, descriptions of ONB’s and TFC’s financial condition, results of operations, asset and credit quality trends and profitability and statements about the expected timing, completion, financial benefits and other effects of the proposed merger.  Forward-looking statements can be identified by the use of the words “anticipate,” “believe,” “expect,” “intend,” “could” and “should,” and other words of similar meaning.  These forward-looking statements express management’s current expectations or forecasts of future events and, by their nature, are subject to risks and uncertainties and there are a number of factors that could cause actual results to differ materially from those in such statements.  Factors that might cause such a difference include, but are not limited to: expected cost savings, synergies and other financial benefits from the proposed merger might not be realized within the expected time frames and costs or difficulties relating to integration matters might be greater than expected; the requisite shareholder and regulatory approvals for the proposed merger might not be obtained; market, economic, operational, liquidity, credit and interest rate risks associated with ONB’s and TFC’s businesses, competition, government legislation and policies (including the impact of the Dodd-Frank Wall Street Reform and Consumer Protection Act and its related regulations); ability of ONB and TFC to execute their respective business plans (including the proposed acquisition of TFC) and satisfy the items addressed  in ONB’s Consent Order with the Office of the Comptroller of the Currency;  changes in the economy which could materially impact credit quality trends and the ability to generate loans and gather deposits; failure or circumvention of either ONB’s or TFC’s internal controls; failure or disruption of our information systems; significant changes in accounting, tax or regulatory practices or requirements; new legal obligations or liabilities or unfavorable resolutions of litigations; other matters discussed in this presentation and other factors identified in ONB’s and TFC’s Annual Reports on Form 10-K and other periodic filings with the Securities and Exchange Commission.  These forward-looking statements are made only as of the date of this presentation, and neither ONB nor TFC undertakes an obligation to release revisions to these forward-looking statements to reflect events or conditions after the date of this presentation. These slides contain non-GAAP financial measures. For purposes of Regulation G, a non-GAAP financial measure is a numerical measure of the registrant's historical or future financial performance, financial position or cash flows that excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the issuer; or includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented.   In this regard, GAAP refers to generally accepted accounting principles in the United States.  Pursuant to the requirements of Regulation G, Old National Bancorp has provided reconciliations within the slides, as necessary, of the non-GAAP financial measure to the most directly comparable GAAP financial measure.

5 Transforming Old National’s Landscape 2004 2013

6 Transforming Old National’s Landscape Returned to community bank model 2004 2005 Sold non- strategic market – Clarksville, TN – 5 branches 2006 Sold non- strategic market – O’Fallon, IL – 1 branch 2007 2008 2009 2010 2011 2012 2013 Acquired St. Joseph Capital – entry into Northern IN market February, 2007 Acquired 65 Charter One branches throughout Indiana   March, 2009 Acquired Monroe Bancorp – Enhanced Bloomington, IN presence  January, 2011 Acquired IN Community – Entry into Columbus, IN  September, 2012 FDIC-assisted acquisition of Integra Bank    July, 2011 Sold non- strategic market – Chicago- area - 4 branches Consolidation of 21 branches Acquired  24 BofA branches  May, 2013 Consolidation of 2 branches Consolidation of 8 branches Consolidation of 1 branch Consolidation of 10 branches Consolidation of 12 branches Consolidation of 44 branches Consolidation of 5 branches Sold  9  branches     + 3 Pending Consolidation of 18 branches + 4 Pending 175 Purchased + 7 Pending 19 Sold + 3 Pending 121 Consolidations + 4 Pending Pending acquisition of Tower Financial

7 ONB to Acquire Tower Financial Strategic fill-in of Ft. Wayne Market 2     largest city in Indiana Old National Bancorp Tower Financial Corporation Tower Financial Corporation¹ NASDAQ: TOFC • Largest independent bank headquartered in Ft. Wayne • 7 full-service banking centers • 6 in Fort Wayne and 1 in Warsaw • $680.9 million total assets • $438.6 million total loans • $619.4 million total liabilities • $581.6 million total deposits • $523.3 million trust assets and over 50,000 HSA accounts Map as of September 10, 2013 per SNL Financial 1 Data as of June 30, 2013, per SNL Financial nd

Bob Jones CEO Old National Bancorp

9 ONB to Acquire TOFC Compelling Strategic Rationale • Strengthen ONB’s objective of being Indiana’s bank by continuing to develop the Northern Indiana region • Adds 7 full service branches - $581.6 million in deposits and $438.6 million in loans • Adds attractive fee businesses with $523.3 in trust assets under management + 50,000 HSA accounts Financially Attractive • Allows Old National to deploy excess capital in an attractive manner • 71% stock / 29% cash deal • Expected EPS accretion of $.08 to $.10 per share in first full year, excluding  acquisition charges • Exceeds internal IRR hurdle • Expected operating efficiencies of 35% • Able to remain under $10 billion Durbin threshold Low Risk Opportunity • Comprehensive due diligence completed • Core competency in integration/conversion processes • Retention of key management members • Complementary customer base and business mix • Long-term relationship with Tower management and board Financial data as of June 30, 2013, per SNL Financial Consideration of 1.20x shares¹ of ONB stock and $6.75 in cash (fixed) for each share of TOFC stock Implied Transaction value of $107.7 million assuming ONB price of $13.52 (as of September 5, 2013) 1 As provided in the merger agreement, the exchange ratio is subject to adjustment (calculated prior to closing) in the event shareholders’ equity of Tower Financial Corporation is below a specified amount

10 Attractive Ft. Wayne, Indiana Market Allen County population of 360,412 – Ft. Wayne population of 254,555 Median HH Income 2012 $45,368 $45,145 $46,817 $50,157 $44,000 $46,000 $48,000 $50,000 $52,000 Ft. Wayne MSA Indiana National Current ONB Projected HH Income Change 2012-2017 17.5% 17.9% 16.2% 13.4% 12% 14% 16% 18% Ft. Wayne MSA Indiana National Current ONB July 2013 Unemployment 8.4% 8.6% 7.4% 6% 7% 8% 9% Allen County Indiana National HH income data per SNL Financial Unemployment data per Indiana Department of Workforce Development and Bureau of Labor Statistics Population data per STATS Indiana Major Employers – Ft. Wayne • Parkview Health Systems – 4,710 • Lutheran Health Network – 4,301 • Ft. Wayne Community Schools – 4,230 • General Motors – 3,880

11 Attractive Warsaw, Indiana Market Kosciusko County population of 77,609 – Warsaw population of 13,815 Median HH Income 2012 $45,368 $45,145 $48,048 $50,157 $44,000 $46,000 $48,000 $50,000 $52,000 Warsaw Indiana National Current ONB Projected HH Income Change 2012-2017 17.5% 17.9% 10.4% 13.4% 10% 12% 14% 16% 18% Warsaw Indiana National Current ONB July 2013 Unemployment 7.4% 6.9% 8.4% 6% 7% 8% 9% Kosciusko County Indiana National HH income data per SNL Financial Unemployment data per Indiana Department of Workforce Development and Bureau of Labor Statistics Population data per STATS Indiana Major Employers – Warsaw • Zimmer – 2,800 • Biomet – 1,610 • Warsaw Community Schools – 1,238 • DePuy – 1,100 The Orthopedic Capital of the World® Headquarters location for three of the world’s five largest orthopedic medical device companies

12 ONB to Acquire TOFC – Highlights Transaction Due Diligence Financial Impact Loans Capital Closing • Consideration:  1.20x shares¹ of ONB and $6.75 in cash (fixed) for each share of TOFC • Assumes 5.6 million shares of ONB common stock issued • Deal value = $107.7 million at ONB price of $13.52 (Sept. 5 closing price) • Price / LTM earnings per share of 15.8x • Price to tangible book of 171% • Comprehensive review of all operations and business lines • Extensive credit review • Obtained in-depth look at culture • Expected to be immediately accretive to EPS in 2014, excluding acquisition charges of approximately $11.5 million • Expected EPS accretion $.08 to $.10 per share in first full year, excluding acquisition charges • No revenue synergies assumed in model • Expected cost saves of over 35%, phased in 50% in 2014 and 100% thereafter • Exceeds internal IRR hurdle • Expected to create goodwill of approximately $80.8 million  • No additional capital raise needed • Transaction anticipated to close 1Q14, subject to regulatory and TOFC shareholder approval and other customary closing conditions • Loan credit mark estimated at $46.1 million, or 10.2% of total gross loans • Loan interest rate mark estimated at $17.3 million 1 As provided in the merger agreement, the exchange ratio is subject to adjustment (calculated prior to closing) in the event shareholders’ equity of Tower Financial Corporation is below a specified amount

13 Pro Forma Capital Ratios ONB            Projected 6-30-2013¹ at Closing² Peer Group Average  6-30-2013³ Tangible Common Equity/Tangible Assets 8.65% 8.07% 8.12% Tangible Common Equity/Risk Weighted Assets 14.23% 13.17% 11.26% Tier 1 Risk-Based Capital 14.4% 13.3% 13.1% Total Risk-Based Capital 15.4% 14.2% 14.5% Tier 1 Leverage Ratio 8.80% 8.17% 9.49% Tangible Book Value Per Share $7.96 $7.68 1 See Appendix for Non GAAP Reconciliation 3 See Appendix for definition of ONB’s Peer Group 2 Assumes ONB actual ratios at June 30, 2013, plus First Call Street estimates, continuation of $.10 quarterly cash  dividend, estimated intangibles of $21 million from July 12, 2013 Bank of America branch purchase and 100% of acquisition charges incurred at closing

14 Purchased Impaired Loan Accretion $31.8 $22.0 Actual mark 12.6% of gross loans Actual mark 14.5% of gross loans Strong credit work out and improved economy have resulted in positive change in accretion income.

15 Tangible Common Book Value 1 Acquired Monroe Bancorp 1-1-11 FDIC acquisition of Integra Bank 7-29-11 1 Non-GAAP financial measure management believes is useful in evaluating the financial results of the Company – see Appendix for Non-GAAP reconciliation Acquired IN Community Bancorp 9-15-12 Old National Bancorp purchased 500,000 shares of ONB stock on the open market during 2Q13

16 Implications of Crossing Over $10 Billion Debit interchange rule (Durbin) – Asset size measured as of year end (December 31) – Effective July 1 of the following year – Estimated pre-tax gross impact of $8 to $12 million per year Can reduce assets to remain under $10 billion threshold – Reduce investment portfolio – Sell residential mortgages – Reduce marked purchased assets

17 Summary ONB has a proven track record of performance – Material earnings accretion – Readily achievable cost saves identified – Revenue potential (not built into model) from Trust and HSA accounts Efficient use of capital Strategic fill-in of attractive Northern Indiana markets Last three bank deals met or exceeded expectations on expense saves, internal rate of return, earnings per share accretion, credit performance and tangible book value earn back Financially attractive

Old National Bancorp Thank You Q&A

Old National Bancorp Appendix

20 Balance Sheet Mix – As of June 30, 2013 Old National Tower Financial Pro Forma Old National Tower Financial Pro Forma Per SNL Financial/company documents

21 Estimated Merger and Acquisition Charges HR related expenses $4.0 Processing and communication expense 4.0 Occupancy expense .7 Professional fees 2.5 Marketing .3 Total estimated merger and acquisition charges $11.5 $ in millions

22 ONB’s M&A Strategy Focus on community banking, client relationships and consistent quality earnings Target geographic markets – Mid-sized markets within or near existing franchise with average to above average growth rates – In market community banks where significant cost saves could be achieved

23 Non-GAAP Reconciliations (end of period balances- $ in millions) ONB at         6-30-2013 Projected at Closing¹ Total Shareholders’ Equity $1,167.0 $1,282.1 Deduct:  Goodwill and Intangible Assets (364.4) (464.2) Tangible Common Shareholders’ Equity $802.6 $817.9 Total Assets $9,641.1 $10,599.7 Add:  Trust Overdrafts .1 -0- Deduct:  Goodwill and Intangible Assets (364.4) (464.2) Tangible Assets $9,276.7 $10,135.5 Tangible Common Equity to Tangible Assets 8.65% 8.07% ONB at         6-30-2013 Projected at Closing¹ Total Shareholders’ Equity $1,167.0 $1,282.1 Deduct:  Goodwill and Intangible Assets (364.4) (464.2) Tangible Common Shareholders’ Equity $802.6 $817.9 Risk Adjusted Assets $5,640.7 $6,210.8 Tangible Common Equity to Risk Weighted Assets 14.23% 13.17% 1 Assumes ONB actual ratios at June 30, 2013, plus First Call Street estimates, continuation of $.10 quarterly cash  dividend, estimated intangibles of $21 million from July 12, 2013 Bank of America branch purchase and 100% of acquisition charges incurred at closing (end of period balances- $ in millions)

24 (end of period balances- $ in millions) ONB at           6-30-2013 Projected at Closing¹ Total Shareholders’ Equity $1,167.0 $1,282.1 Deduct:  Goodwill and Intangible Assets (364.4) (464.2) Tangible Common Shareholders’ Equity $802.6 $817.9 Common Shares Issued and Outstanding 100.881 106.510 Tangible Book Value per Share $7.96 $7.68 Non-GAAP Reconciliations $ in millions Tangible Common Equity – 3/31/2013 $834.2 2Q Earnings 28.5 2Q Share Repurchase (6.5) 2Q Dividend (10.1) Changes in OCI – Securities (46.5) Changes in OCI – Other 1.9 Changes in Goodwill & Intangibles 1.1 Tangible Common Equity – 6/30/2013 $802.6 1 Assumes ONB actual ratios at June 30, 2013, plus First Call Street estimates, continuation of $.10 quarterly cash  dividend, estimated intangibles of $21 million from July 12, 2013 Bank of America branch purchase and 100% of acquisition charges incurred at closing

25 ONB’s Peer Group 1st Source Corporation SRCE Heartland Financial USA, Inc. HTLF BancFirst Corporation BANF IBERIABANK Corporation IBKC BancorpSouth, Inc. BXS MB Financial, Inc. MBFI Bank of Hawaii Corporation BOH Park National Corporation PRK Chemical Financial Corporation CHFC Pinnacle Financial Partners, Inc. PNFP Commerce Bancshares, Inc. CBSH Prosperity Bancshares, Inc. PB Cullen/Frost Bankers, Inc. CFR Renasant Corp. RNST F.N.B. Corporation FNB S&T Bancorp, Inc. STBA First Commonwealth Financial Corporation FCF Susquehanna Bancshares, Inc. SUSQ First Financial Bancorp. FFBC Trustmark Corporation TRMK First Interstate BancSystem, Inc. FIBK UMB Financial Corporation UMBF First Merchants Corporation FRME United Bankshares, Inc. UBSI First Midwest Bancorp, Inc. FMBI Valley National Bancorp VLY FirstMerit Corporation FMER WesBanco, Inc. WSBC Fulton Financial FULT Wintrust Financial Corporation WTFC Glacier Bancorp, Inc. GBCI Like-size, publicly-traded financial services companies, generally in the Midwest, serving comparable demographics with comparable services as ONB