SUMMARY

This summary highlights selected information from this proxy statement/prospectus and may not contain all of the information that is important to you. You are encouraged to read carefully this entire proxy statement/prospectus and the other documents referred to in this proxy statement/prospectus because the information in this section does not provide all of the information that might be important to you with respect to the merger agreement, the merger and the other matters being considered at the Special Meeting. See “Where You Can Find More Information” on page 146. The merger agreement is attached as Annex A to this proxy statement/prospectus and is incorporated herein by reference. You are encouraged to read it, as it is the most important legal document that governs the merger. Page references are included in parentheses to direct you to a more complete description contained elsewhere in this proxy statement/prospectus of the topics presented in this summary. In addition, Stifel and KBW encourage you to read the information incorporated by reference into this proxy statement/prospectus, which includes important business and financial information about Stifel and KBW that has been filed with the Securities and Exchange Commission, which is referred to as the SEC in this proxy statement/prospectus. You may obtain the information incorporated by reference into this proxy statement/prospectus without charge by following the instructions in the section titled “Where You Can Find More Information” beginning on page 146 of this proxy statement/prospectus.

The Companies

Stifel Financial Corp.

501 North Broadway

St. Louis, Missouri 63102

(314) 342-2000

Stifel (NYSE: SF) is a financial services holding company headquartered in St. Louis. Stifel operates 339 offices in 45 states, the District of Columbia and in certain foreign countries. Its principal subsidiary is Stifel, Nicolaus & Company, Incorporated, a full-service retail and institutional brokerage and investment banking firm. Stifel, with operations in two business segments: Global Wealth Management and Institutional Group, provides securities brokerage, investment banking, trading, investment advisory, and related financial services, primarily, to individual investors, professional money managers, businesses, and municipalities. Stifel Bank & Trust, a Missouri retail and commercial bank, offers a full range of consumer and commercial lending solutions.

The Global Wealth Management segment consists of two businesses, the private client group and Stifel Bank. The private client group includes branch offices and independent contractor offices of Stifel’s broker-dealer subsidiaries located throughout the United States, primarily in the Midwest and Mid-Atlantic regions with a growing presence in the Northeast, Southeast and Western United States. These branches provide securities brokerage services, including the sale of equities, mutual funds, fixed income products, and insurance, as well as offering banking products to their private clients through Stifel Bank, which provides residential, consumer, and commercial lending, as well as FDIC-insured deposit accounts to customers of Stifel’s broker-dealer subsidiaries and to the general public.

The Institutional Group segment includes institutional sales and trading. It provides securities brokerage, trading, and research services to institutions with an emphasis on the sale of equity and fixed income products. This segment also includes the management of and participation in underwritings for both corporate and public finance (exclusive of sales credits, which are included in the Global Wealth Management segment), merger and acquisition, and financial advisory services.

Additional information about Stifel and its subsidiaries is included in documents incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 146.

KBW, Inc.

787 Seventh Avenue

New York, New York 10019

(212) 887-7777

KBW (NYSE: KBW) is a full service investment bank specializing in the financial services industry. KBW’s principal activities are: (i) investment banking, including mergers and acquisitions, and other strategic advisory services, equity and fixed income securities offerings, and mutual thrift conversions, (ii) equity and fixed income sales and trading, and (iii) research that provides fundamental, objective analysis that identifies investment opportunities and helps our investor customers make better investment decisions.

Within KBW’s full service business model, its focus includes bank and thrift holding companies, banks, thrifts, insurance companies, broker-dealers, mortgage banks, asset management companies, real estate investment trusts, consumer and specialty finance firms, financial processing companies and securities exchanges. As of January 3, 2013, KBW’s research department covered an aggregate of 556 financial services companies, including 443 companies in the United States and Canada, and 113 in Europe.

Additional information about KBW and its subsidiaries is included in documents incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 146.

SFKBW One, Inc.

SFKBW One, Inc., sometimes referred to in this proxy statement/prospectus as Merger Sub, is a newly-formed and wholly-owned subsidiary of Stifel. If Stifel and KBW complete the merger, Merger Sub will be merged with and into KBW, with KBW becoming a wholly-owned subsidiary of Stifel. Merger Sub was organized solely for use in the merger. Merger Sub has not carried on any activities to date, except for activities incidental to its formation and activities undertaken in connection with the transactions contemplated by the merger agreement.

SFKBW Two, LLC

SFKBW Two, LLC, sometimes referred to in this proxy statement/prospectus as Successor Sub, is a Delaware limited liability company that is wholly owned by and disregarded from Stifel for U.S. federal income tax purposes. As described above, following the merger, KBW, as a wholly-owned subsidiary of Stifel, will be merged with and into the Successor Sub, whereupon the Successor Sub will be the surviving limited liability company as a direct wholly-owned subsidiary of Stifel. Successor Sub was organized solely for use in the second-step merger. Successor Sub has not carried on any activities to date, except for activities incidental to its formation and activities undertaken in connection with the transactions contemplated by the merger agreement.

Recent Developments

On December 21, 2012, Stifel issued $150,000,000 aggregate principal amount of its 5.375% Senior Notes due December 2022 (“Senior Notes”). Interest on the Senior Notes accrues from December 21, 2012 and will be paid quarterly in arrears on January 15, April 15, July 15 and October 15 of each year, commencing on April 15, 2013. The Senior Notes will mature on December 31, 2022. Stifel may redeem the Senior Notes in whole or in part on or after December 31, 2015 at its option at a redemption price equal to 100% of their principal amount, plus accrued and unpaid interest to the date of redemption. Proceeds from such notes issuance of $145 million, after discounts, commissions and expenses, will be used for general corporate purposes.

The Merger

(see page 104)

Stifel and KBW agreed to the acquisition of KBW by Stifel under the terms of the merger agreement that is described in this proxy statement/prospectus. Pursuant to the merger agreement, Merger Sub will merge with and into KBW, with KBW continuing as a wholly-owned subsidiary of Stifel. Following the merger, KBW, as a wholly-owned subsidiary of Stifel, will be merged with and into the Successor Sub, whereupon the Successor Sub will be the surviving limited liability company as a direct wholly-owned subsidiary of Stifel.

Stifel and KBW have attached the merger agreement as Annex A to this proxy statement/prospectus. Stifel and KBW encourage you to read carefully the merger agreement in its entirety because it is the legal document that governs the merger.

Effects of the Merger; Merger Consideration

(see page 104)

In the merger, each issued and outstanding share of KBW common stock (other than shares owned by KBW as treasury stock, shares of KBW common stock owned by Stifel, shares for which appraisal rights have been properly exercised and perfected under the General Corporation Law of the State of Delaware and certain shares of KBW common stock subject to continuing restricted share awards, continuing RSU awards and other equity awards, as described under “—Treatment of KBW Equity-Based Awards” below) will be automatically converted into the right to receive a combination of (i) cash consideration of $8.00 ($10.00 less the per share extraordinary dividend amount of $2.00) and (ii) stock consideration of a fraction of a share of Stifel common stock equal to the exchange ratio, as described below.

The merger agreement defines a per share extraordinary dividend amount, which reduces the cash consideration by an equal amount up to $2.00, to be equal to (i) the aggregate amount of all dividends paid by KBW after the date of the merger agreement and before the closing date of the merger (other than quarterly dividends consistent with past practice that are paid on or prior to December 31, 2012) (ii) divided by the number of issued and outstanding KBW shares immediately prior to the closing date of the merger. The merger agreement provides that extraordinary dividends will not exceed $2.00. On November 29, 2012, the KBW board of directors declared an extraordinary dividend of $2.00 per share of KBW’s common stock, payable to stockholders of record on December 10, 2012, which was paid on December 17, 2012.

The number of shares of Stifel common stock KBW stockholders (other than those holders described above) receive will depend on the average of the volume weighted average trading prices of Stifel common stock on each of the ten trading days ending on the trading day immediately prior to the closing date of the merger. If the average of the daily volume weighted average trading prices of Stifel common stock during this valuation period is between $29.00 and $35.00, then current KBW stockholders will receive a number of shares of Stifel common stock equal to a fraction, the numerator of which equals $7.50 and the denominator of which is the average of the daily volume weighted average trading prices of Stifel common stock during this valuation period, rounding the result to the nearest 1/10,000, as the stock consideration for each share of KBW common stock. If the average of the daily volume weighted average trading prices of Stifel common stock during the valuation period is less than or equal to $29.00, then current KBW stockholders will receive 0.2586 shares of Stifel common stock as the stock consideration for each share of KBW common stock. If the average of the daily volume weighted average trading prices of Stifel common stock during the valuation period is greater than or equal to $35.00, then current KBW stockholders will receive 0.2143 shares of Stifel common stock as the stock consideration for each share of KBW common stock.

Holders of KBW common stock will receive cash in lieu of any fractional shares of Stifel common stock they otherwise would have received in the merger. Each KBW stockholder who would otherwise have been entitled to receive a fraction of a share of Stifel common stock will receive an amount in cash (without interest and subject to

withholding taxes) equal to the product obtained by multiplying (1) the fractional share interest to which such holder (after taking into account all fractional share interests then held by such holder) would otherwise be entitled (rounded to the nearest one-hundredth of a share) by (2) the average of the daily volume weighted average trading prices of Stifel common stock on each of the ten trading days prior to the closing date of the merger.

The $8.00 in cash ($10.00 less the per share extraordinary dividend amount of $2.00) and the number of shares of Stifel common stock to be received by holders of KBW common stock in the merger are referred to collectively as the “merger consideration”.

The merger agreement provides that the exchange ratio will be appropriately adjusted to reflect the effect of any stock split, reverse stock split, stock dividend, reclassification or other similar change with respect to Stifel common stock or KBW common stock, or securities convertible or exchangeable into or exercisable into Stifel common stock or KBW common stock, with a record date occurring on or after the date of the merger agreement and prior to the effective time of the merger.

The exchange ratio will be determined shortly before completion of the merger. On December 31, 2012, the latest practicable date before the date of this proxy statement/prospectus, Stifel common stock closed on the New York Stock Exchange (the “NYSE”), at $31.97. The average of the daily volume weighted average trading price per share of Stifel common stock on the last ten trading days before December 31, 2012, was $31.6984. If this were the volume weighted average trading price per share of Stifel common stock used to calculate the exchange ratio, the exchange ratio would be 0.2366, which would result in total consideration of $15.56. The actual exchange ratio and, accordingly, the actual number of shares of Stifel common stock issued in respect of each share of KBW common stock in the merger, may differ from this example and will not be known at the Special Meeting because the valuation period will not be complete until after the Special Meeting.

For a full description of the merger consideration, see “Proposal One: The Merger Agreement—Merger Consideration” beginning on page 104 of this proxy statement/prospectus.

Treatment of KBW Equity-Based Awards

(see page 106)

Restricted Stock and RSU Awards. At or immediately prior to the effective time of the merger, all outstanding awards of KBW restricted stock and awards of restricted stock units, other than continuing awards, as discussed below, to the extent not currently vested, will fully vest and convert into the right to receive the merger consideration for each KBW share granted pursuant to, or subject to, such awards, subject to any applicable tax withholding.

Continuing Restricted Stock and RSU Awards. At or immediately prior to the effective time of the merger, all outstanding continuing restricted share awards and all outstanding continuing RSU awards will convert into the right to receive the number of shares of Stifel common stock equal to the product (rounded up to the nearest whole number in case of continuing restricted share awards) of (i) the number of shares of KBW common stock subject to such continuing restricted share award or continuing RSU award immediately prior to the effective time of the merger and (ii) the equity exchange ratio, subject to any applicable tax withholding (as described below).

Other Awards. At the effective time of the merger, each other equity award shall be deemed to be converted into the right to acquire or receive benefits measured by the value of the number of shares of Stifel common stock equal to the product of (i) the number of shares of KBW common stock subject to such other equity award and (ii) the equity exchange ratio, subject to any applicable tax withholding. Following the completion of the merger, each such other equity award shall continue to be governed by the same terms and conditions as were applicable under such award immediately prior to the merger.

The “equity exchange ratio” will depend on the average of the volume weighted average trading prices of Stifel common stock on each of the ten trading days ending on the trading day immediately prior to the closing date of the merger. The equity exchange ratio is a fraction, the numerator of which equals $15.50 ($17.50 less the per share extraordinary dividend amount of $2.00) (as discussed above) and the denominator of which equals (i) $29.00, if the average of such daily volume weighted average trading prices of Stifel common stock during the valuation period is less than or equal to $29.00, (ii) the average of such daily volume weighted average trading prices of Stifel common stock during the valuation period, if such average is greater than $29.00 and less than $35.00 and (iii) $35.00, if the average of such daily volume weighted average trading prices of Stifel common stock during the valuation period is greater than or equal to $35.00, in each case rounding the result to the nearest 1/10,000.

Performance Shares. The outstanding KBW performance share awards will be forfeited pursuant to waiver agreements with the performance share award holders.

Risk Factors

(see page 45)

In addition to the other information contained in or incorporated by reference into this proxy statement/prospectus, you should carefully consider the factors discussed under the caption entitled “Risk Factors” beginning on page 45 in deciding whether to vote in favor of the proposal to adopt the merger agreement and thereby to approve the transactions contemplated by the merger agreement, including the merger.

This proxy statement/prospectus (including the documents incorporated by reference into this proxy statement/prospectus) contains forward-looking statements that involve risks, uncertainties and assumptions, such as statements of Stifel’s, KBW’s and the combined company’s plans, objectives, expectations and intentions. When used in this proxy statement/prospectus and the documents incorporated by reference into this proxy statement/prospectus, the words as “may”, “might”, “should”, “expects”, “anticipates”, “believes”, “estimates”, “intends”, “plans”, “seeks”, “will”, “should”, “would”, “projects”, “predicts”, “continues” and similar expressions or the negatives of these terms and other comparable terminology are intended to identify certain of these forward-looking statements. Because these forward-looking statements involve risks, uncertainties and assumptions, including those discussed under the caption entitled “Risk Factors”, the actual results of Stifel, KBW and the combined company could differ materially from those expressed or implied by the forward-looking statements in this proxy statement/prospectus and the documents incorporated by reference into this proxy statement/prospectus.

The Special Meeting; KBW Stockholders Entitled to Vote; Required Vote

(see page 57)

The Special Meeting of KBW stockholders will be held on February 12, 2013 at 10:00 a.m., Eastern time, at 1271 Avenue of the Americas (Time Life Building), Luce Room, New York, New York. At the Special Meeting, KBW stockholders will be asked to:

The close of business on December 24, 2012 was the record date for the Special Meeting. Only KBW stockholders on the record date are entitled to notice of and to vote at the Special Meeting. Each share of KBW common stock will be entitled to one vote on each matter to be acted upon at the Special Meeting. On the record date, there were 34,557,980 shares of KBW common stock outstanding and entitled to vote at the Special Meeting.

The approval of holders of a majority of the outstanding shares of KBW common stock is required to adopt the merger agreement and thereby to approve the transactions contemplated by the merger agreement, including the merger. Approval of the affirmative vote of a majority of the shares of KBW common stock represented (in person or by proxy) at the Special Meeting and entitled to vote on such proposal is required for the proposal to approve, by non-binding advisory vote, certain compensation arrangements for KBW’s named executive officers in connection with the merger; and for the proposal to approve the adjournment of the Special Meeting.

Recommendation of the KBW Board of Directors and KBW’s Reasons for the Merger

(See page 68)

Acting upon the unanimous recommendation of its committee of independent directors, and after careful consideration of the numerous factors described in the section entitled “Proposal One: The Merger—KBW’s Reasons for the Merger; Recommendation of the KBW Board of Directors” beginning on page 68 of this proxy statement/prospectus, the KBW board of directors has unanimously determined that the merger and the merger agreement are advisable, and are fair to, and in the best interests of, KBW and its stockholders. Accordingly, the KBW board of directors recommends that you vote FOR the proposal to adopt the merger agreement and thereby to approve the transactions contemplated by the merger agreement, including the merger.

In addition, the KBW board of directors recommends that you vote FOR the proposal to approve, by non-binding advisory vote, certain compensation arrangements for KBW’s named executive officers in connection with the merger.

Finally, the KBW board of directors recommends that you vote FOR the adjournment of the Special Meeting, if necessary, for any purpose, including to solicit additional proxies in favor of the adoption of the merger agreement and thereby the approval of the transactions contemplated by the merger agreement, including the merger.

Opinions of KBW’s Financial Advisors

(See page 71)

In connection with the transaction, each of KBW’s financial advisors, Merrill Lynch, Pierce, Fenner & Smith Incorporated (which we refer to as BofA Merrill Lynch) and Keefe, Bruyette & Woods, Inc. (which we refer to as Keefe, Bruyette & Woods), delivered a written opinion, dated November 4, 2012, to KBW’s board of directors as to the fairness, from a financial point of view and as of such date, of the merger consideration to be received pursuant to the merger agreement by holders of KBW common stock. For purposes of the opinions of KBW’s financial advisors and the descriptions of such opinions in this proxy statement/prospectus, the cash portion of the merger consideration was inclusive of the extraordinary dividend amount permitted to be paid as of the date of such opinions, which dividend amount subsequently was paid on December 17, 2012. The full text of BofA Merrill Lynch’s written opinion and Keefe, Bruyette & Woods’s written opinion, each dated November 4, 2012, to KBW’s board of directors, which describe, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken, are attached to this proxy statement/prospectus as Annex B and Annex C, respectively. BofA Merrill Lynch and Keefe, Bruyette & Woods delivered their respective opinions to KBW’s board of directors for the benefit and use of KBW’s board of directors (in its capacity as such) in connection with and for purposes of its evaluation of the merger consideration from a financial point of view. Neither BofA Merrill Lynch’s opinion nor Keefe, Bruyette & Woods’s opinion addressed any other aspect of the transaction and no opinion or view was expressed as to

the relative merits of the transaction in comparison to other strategies or transactions that might be available to KBW or in which KBW might engage or as to the underlying business decision of KBW to proceed with or effect the transaction. Neither BofA Merrill Lynch nor Keefe, Bruyette & Woods expressed an opinion or recommendation as to how any stockholder should vote or act in connection with the transaction or any related matter.

No Stifel Stockholder Approval

(See page 97)

Stifel stockholders are not required to adopt the merger agreement or approve the merger or the issuance of shares of Stifel common stock as part of the merger consideration.

Interests of Certain Persons in the Merger

(See page 89)

When considering the recommendation by the KBW board of directors to vote FOR the proposal to adopt the merger agreement and thereby to approve the transactions contemplated by the merger agreement, including the merger, you should be aware that directors and executive officers of KBW have interests in the merger, including financial interests, that may be different from, or in addition to, your interests. Stifel currently anticipates that the senior management of KBW, including several of its executive officers, will be executive officers and/or key employees of Stifel following the merger. Mr. Thomas B. Michaud, Chief Executive Officer, President and Vice Chairman of KBW, Mr. John G. Duffy, Vice Chairman of KBW, and Mr. Andrew M. Senchak, Chairman of KBW, have each entered into an employment agreement or offer letter with Stifel that is conditioned on completion of the merger and provides certain retention and/or severance benefits as discussed below. Messrs. Michaud, Duffy and Senchak have agreed to waive all rights under their existing employment agreements with KBW, waive the change in control vesting provisions of their outstanding restricted share awards and forfeit their outstanding performance share and cash incentive awards. Directors, officers or employees of KBW who hold restricted stock awards or vested restricted stock units pursuant to existing plans may receive certain benefits upon the merger, including accelerated vesting of those restricted stock awards or delivery of those restricted stock units, as well as other retention or special awards in connection with the merger. Additionally, some officers and employees of KBW may, pursuant to employment or change of control agreements with KBW, be entitled to the payment of severance obligations upon certain qualifying terminations of employment that may occur in connection with or following the merger. KBW directors and officers will also receive indemnification from Stifel, and Stifel has agreed to provide and pay for liability insurance benefits for members of the KBW board of directors and KBW officers. The committee of independent directors of the KBW board of directors was aware of these interests and considered them in its recommendation to approve the merger agreement and the merger. The KBW board of directors was aware of these interests and considered them in approving the merger agreement and the merger.

Security Ownership by Directors and Executive Officers of KBW

(See page 142)

As of the record date for the Special Meeting, the directors and executive officers of KBW and their affiliates, as a group, beneficially owned and were entitled to vote approximately 3.11% of the outstanding shares of KBW common stock entitled to vote at the Special Meeting. The approval of the holders of a majority of the outstanding shares of KBW common stock is required to adopt the merger agreement and thereby to approve the transactions contemplated by the merger agreement, including the merger.

Ownership of Stifel Following the Merger

(See page 97)

If the merger is completed, holders of KBW common stock collectively will receive up to approximately 8.3 million shares of Stifel common stock in the merger.

Based on the number of shares of Stifel common stock and KBW common stock outstanding as of December 31, 2012, current KBW stockholders are expected to own up to approximately 13% of the outstanding common stock of Stifel following the merger (without giving effect to any shares of Stifel common stock held by KBW stockholders prior to the merger).

Listing of Stifel Common Stock and Delisting and Deregistration of KBW Common Stock

(See page 103)

Application will be made to have the shares of Stifel common stock issued in the merger approved for listing on the NYSE. If the merger is completed, KBW common stock will no longer be listed on the NYSE and will be deregistered under the Exchange Act, and KBW will no longer file periodic reports with the SEC.

Regulatory Approvals

(See page 99)

Stifel and KBW have both agreed to use their reasonable best efforts to apply for and obtain all regulatory approvals necessary or advisable in connection with the transactions contemplated by the merger agreement. They have made applications for regulatory approvals from the Financial Industry Regulatory Authority and the United Kingdom Financial Services Authority, among others.

The Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, or the HSR Act, prohibits Stifel and KBW from completing the merger until Stifel and KBW have furnished certain information and materials to the Antitrust Division of the Department of Justice and the Federal Trade Commission and the required waiting period has expired or been terminated. Stifel and KBW each filed the required notification and report forms on November 15, 2012. On November 23, 2012, the Federal Trade Commission granted early termination of the waiting period under the HSR Act.

Appraisal Rights

(See page 99)

KBW stockholders will have the right to demand appraisal of their shares of KBW common stock and obtain payment in cash for the fair value of their shares, but only if they perfect their appraisal rights and comply with the applicable provisions of Delaware law. A copy of the Delaware statutory provisions related to appraisal rights is attached as Annex D to the this proxy statement/prospectus, and a summary of these provisions can be found under “Proposal One: The Merger—Appraisal Rights” beginning on page 99. Due to the complexity of the procedures for exercising the right to seek appraisal, KBW stockholders who are considering exercising such rights are encouraged to seek the advice of legal counsel. Failure to strictly comply with the applicable DGCL provisions will result in the loss of the right of appraisal.

Conditions to Complete The Merger

(See page 116)

Each of Stifel’s, Merger Sub’s and KBW’s obligation to effect the merger is subject to the satisfaction (or, to the extent permissible, waiver) of a number of conditions, including:

Expected Timing of the Merger

(See page 3)

Stifel and KBW are working toward completing the merger as quickly as possible. The merger is expected to close during the first quarter of 2013, subject to receipt of KBW stockholder approval, governmental and regulatory approvals and the satisfaction of other usual and customary closing conditions. However, no assurance can be given as to when, or if, the merger will occur.

Termination

(See page 117)

Stifel and KBW may mutually agree to terminate the merger agreement before completing the merger, even after KBW stockholder approval. In addition, either of Stifel or KBW may terminate the merger agreement under certain circumstances, including:

Stifel may also terminate the merger agreement if:

KBW may terminate the merger agreement if:

Termination Fees

(See page 119)

Termination Fees Payable by KBW

Under the terms of the merger agreement, KBW would be obligated to pay Stifel a $17,255,000 cash termination fee if:

Material United States Federal Income Tax Consequences of the Merger

(See page 132)

The merger, together with the second-step merger, is intended to qualify as a reorganization under Section 368(a) of the Code, and will so qualify provided that the value of the shares of Stifel common stock delivered to KBW stockholders in the merger, valued as of the closing date, is sufficient to meet certain requirements more fully discussed below in “Material United States Federal Income Tax Consequences of the Merger” beginning on page 132. If the value of the shares of Stifel common stock delivered to KBW stockholders in the merger is not sufficient to meet these requirements, the transaction will not qualify as a reorganization under Section 368(a) of the Code.

It will not be known at the time of the special meeting whether the transaction will qualify as a reorganization under Section 368(a) of the Code and, therefore, the U.S. federal income tax treatment of the transactions contemplated by the merger agreement will not be known at such time.

If the transaction qualifies as a reorganization under Section 368(a) of the Code, U.S. holders of KBW common stock receiving both Stifel common stock and cash pursuant to the merger agreement will generally recognize gain, but not loss, equal to the lesser of (i) the amount of cash treated as received in exchange for KBW common stock in the merger and (ii) the excess of the “amount realized” in the transaction (i.e., the fair market value of the Stifel common stock at the effective time of the merger plus the amount of cash treated as received in exchange for KBW common stock in the merger) over their tax basis in their surrendered KBW common stock. In certain circumstances, such gain could be taxable as a dividend rather than capital gain.

To review the tax consequences to stockholders in greater detail, see “Material United States Federal Income Tax Consequences of the Merger” beginning on page 132.

You are encouraged to consult your tax advisor as to the tax consequences of the merger in your particular circumstances, including the applicability and effect of the alternative minimum tax and any state, local or foreign and other tax laws and of changes in those laws.

The U.S. federal income tax consequences described above may not apply to all holders of KBW common stock. Your tax consequences will depend on your individual situation. Accordingly, you are urged to consult your tax advisor for a full understanding of the particular tax consequences of the merger to you.

Accounting Treatment

(See page 98)

In accordance with accounting principles generally accepted in the United States, Stifel will account for the merger using the acquisition method of accounting for business combinations.

Comparison of Rights of KBW Stockholders and Stifel Stockholders

(See page 121)

KBW’s certificate of incorporation and by-laws and Delaware corporate law govern the rights of KBW stockholders. Stifel’s certificate of incorporation and by-laws and Delaware corporate law will govern your rights as a stockholder of Stifel following the merger. Your rights under Stifel’s certificate of incorporation and by-laws will differ in some respects from your rights under KBW’s certificate of incorporation and by-laws.