As filed with the Securities and Exchange Commission on June 19, 2018.

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

STIFEL FINANCIAL CORP.

(Exact name of registrant as specified in its charter)

501 North Broadway

St. Louis, MO 63102

(314) 342-2000

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

James M. Zemlyak

Co-President and Chief Financial Officer

Stifel Financial Corp.

501 North Broadway

St. Louis, MO 63102

(314) 342-2000

(Name, address, including zip code, and telephone number, including area code, of agent for service)

With copies to:

Approximate date of commencement of the proposed sale of the securities to the public:

As soon as practicable after this registration statement becomes effective and upon completion of the merger described in the enclosed document.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box.  ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, as amended, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)  ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)  ☐

CALCULATION OF REGISTRATION FEE

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act, or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

Information contained herein is subject to completion or amendment. A registration statement relating to these securities has been filed with the Securities and Exchange Commission. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This document shall not constitute an offer to sell or the solicitation of any offer to buy, nor shall there be any sale of, these 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.

PRELIMINARY—SUBJECT TO COMPLETION—DATED JUNE 19, 2018

BUSINESS BANCSHARES, INC.		STIFEL FINANCIAL CORP.

PROXY STATEMENT/PROSPECTUS

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

On May 10, 2018, Stifel Financial Corp. (which we refer to as “Stifel”) and Business Bancshares, Inc. (which we refer to as “BBI”) entered into an Agreement and Plan of Merger (which we refer to as the “merger agreement”) that provides for the acquisition of BBI by Stifel. Pursuant to the merger agreement, Stifel will form a Missouri corporation as a special-purpose, wholly owned subsidiary of Stifel (which we refer to as “Merger Sub”), which will merge with and into BBI, with BBI as the surviving corporation (which we refer to as the “surviving corporation”), in a transaction we refer to as the “merger.” As a result of the merger, BBI will be a wholly owned subsidiary of Stifel.

In the merger, each outstanding share of common stock of BBI (which we refer to as “BBI common stock”), including both the common stock, $0.01 par value per share, of BBI (which we refer to as “BBI voting common stock”) and the non-voting common stock, $0.01 par value per share, of BBI (which we refer to as “BBI non-voting common stock”), except for shares of BBI common stock held by BBI as treasury stock, certain shares held by Stifel, if any, and shares held by holders of BBI common stock (which we refer to as “BBI shareholders”) who properly exercise their rights under Missouri law to dissent from the merger, automatically will be converted into the right to receive 0.705 shares (which we refer to as the “exchange ratio”) of common stock, $0.15 par value per share, of Stifel (which we refer to as “Stifel common stock”). Although the number of shares of Stifel common stock that each BBI shareholder will receive is fixed, the market value of those shares will fluctuate with the market price of Stifel common stock both prior to and after the time BBI shareholders vote on the merger. Stifel common stock is traded on the New York Stock Exchange (which we refer to as the “NYSE”) and the Chicago Stock Exchange under the symbol “SF.” Based on the closing price of Stifel common stock on the NYSE on May 9, 2018, the last trading day before the date of the public announcement of the merger, the exchange ratio represented approximately $42.46 in value for each share of BBI common stock. Based on Stifel’s closing price of $[        ] on [                    ], 2018, the last practicable trading day before the date of this proxy statement/prospectus, the exchange ratio represented approximately $[        ] in value for each share of BBI common stock. Based on the exchange ratio and the number of shares of BBI common stock outstanding and reserved for issuance upon the exercise of outstanding options granted by BBI to purchase shares of BBI common stock under the BBI Incentive Stock Option Plan (as revised) as of [                    ], 2018, the maximum number of shares of Stifel common stock issuable in the merger is [                ]. We urge you to obtain current market quotations for Stifel common stock.

BBI will hold a special meeting of its shareholders (which we refer to as the “special meeting”) in connection with the merger. Holders of BBI voting common stock will be asked to vote to adopt and approve the merger agreement, the related plan of merger to be entered into by and between Merger Sub and BBI in the form attached as Exhibit B to the merger agreement (which we refer to as the “plan of merger”) and the merger, as described in the attached proxy statement/prospectus. Adoption and approval of the merger agreement, the related plan of merger and the merger require the affirmative vote of the holders of two-thirds of the outstanding shares of BBI common stock entitled to vote.

The holders of outstanding shares of BBI non-voting common stock are not entitled or permitted to vote any shares of BBI non-voting common stock at the special meeting.

The special meeting will be held on [                    ], 2018, at 8:00 a.m. local time, at BBI’s corporate office at 8000 Maryland Ave., 14th Floor Boardroom, Clayton, Missouri 63105.

BBI’s board of directors unanimously recommends that holders of BBI voting common stock vote “FOR” the adoption and approval of the merger agreement, the related plan of merger and the merger and “FOR” the proposal to adjourn the special meeting to a later date or dates, if necessary or appropriate, including to permit further solicitation of proxies in favor of the merger proposal if there are not sufficient votes to approve it.

The attached proxy statement/prospectus describes the special meeting, the merger, the documents related to the merger and other related matters. Please carefully read the entire proxy statement/prospectus, including “Risk Factors,” beginning on page 24, for a discussion of the risks relating to the proposed merger. You also can obtain information about Stifel from documents that it has filed with the Securities and Exchange Commission.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be issued in the merger or passed upon the adequacy or accuracy of this proxy statement/prospectus. Any representation to the contrary is a criminal offense.

The securities to be issued in the merger are not savings or deposit accounts or other obligations of any bank or savings association, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

The date of this proxy statement/prospectus is [                    ], 2018, and it is first being mailed or otherwise delivered to the shareholders of BBI on or about [                    ], 2018.

BUSINESS BANCSHARES, INC.

8000 Maryland Ave., Suite 100

Clayton, Missouri 63105

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

TO BE HELD ON [                    ], 2018

NOTICE IS HEREBY GIVEN that Business Bancshares, Inc. (which we refer to as “BBI”) will hold a special meeting of its shareholders (which we refer to as the “special meeting”) on [                    ], 2018, at 8:00 a.m. local time, at BBI’s corporate office at 8000 Maryland Ave., 14th Floor Boardroom, Clayton, Missouri 63105.

The special meeting is for the holders of the common stock, $0.01 par value per share, of BBI (which we refer to as “BBI voting common stock”) to consider and vote upon the following matters:

Any action may be taken on the foregoing proposals at the special meeting on the date specified above or on any date or dates to which, by original or later adjournment or postponement, the special meeting may be adjourned.

We have fixed the close of business on [                    ], 2018, as the record date for the special meeting. Only holders (which we refer to as “BBI shareholders”) of record of the common stock of BBI (which we refer to as “BBI common stock”), including both the BBI voting common stock and the non-voting common stock, $0.01 par value per share, of BBI, at that time are entitled to notice of, and only holders of BBI voting common stock are entitled to vote at, the special meeting or any adjournment or postponement of the special meeting. Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of BBI voting common stock. Approval of the adjournment proposal requires a majority of the outstanding shares of BBI common stock entitled to vote on the proposal and present at the special meeting, in person or by proxy, to be voted in favor of such proposal.

Your vote is very important. We cannot complete the merger unless the holders of BBI voting common stock adopt and approve the merger proposal.

Regardless of whether you plan to attend the special meeting, please vote as soon as possible. If you hold BBI voting common stock in your name as a shareholder of record of BBI, please complete, sign, date and return the accompanying proxy card in the enclosed postage-paid return envelope as soon as possible. The proxy card will not be used if you attend and vote at the special meeting in person. If you hold your BBI voting common stock in “street name” through a broker, bank or other nominee, please follow the directions on the voting instruction card furnished by the record holder in order to vote those shares.

This proxy statement/prospectus provides a detailed description of the special meeting, the merger, the documents related to the merger and other related matters. We urge you to read this proxy statement/prospectus, including any documents incorporated into this proxy statement/prospectus by reference, and its annexes carefully and in their entirety.

Date:      [                     ], 2018

Clayton, Missouri

BY ORDER OF BBI’S BOARD OF DIRECTORS,

Edward G. Throop

Chairman of the Board

Business Bancshares, Inc.

BBI’S BOARD OF DIRECTORS UNANIMOUSLY APPROVED THE MERGER AGREEMENT, THE RELATED PLAN OF MERGER AND THE MERGER, DETERMINED THAT THE MERGER AGREEMENT, THE RELATED PLAN OF MERGER AND THE MERGER ARE IN THE BEST INTERESTS OF BBI AND ITS SHAREHOLDERS, DECLARED THE MERGER TO BE ADVISABLE AND UNANIMOUSLY RECOMMENDS THAT THE HOLDERS OF BBI VOTING COMMON STOCK VOTE “FOR” THE MERGER PROPOSAL AND “FOR” THE ADJOURNMENT PROPOSAL.

REFERENCES TO ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates important business and financial information about Stifel from documents filed with the Securities and Exchange Commission (which we refer to as the “SEC”) that are not included in or delivered with this proxy statement/prospectus. You can obtain any of the documents filed with or furnished to the SEC by Stifel at no cost from the SEC’s website at http://www.sec.gov. You may also request copies of these documents, including documents incorporated by reference into this proxy statement/prospectus, at no cost by contacting Stifel at the following address:

Stifel Financial Corp.

501 N. Broadway

St. Louis, Missouri 63102

Attention: Joel Jeffrey

(212) 271-3610

You will not be charged for any of these documents that you request. To obtain timely delivery of these documents, you must request them no later than five business days before the date of the special meeting. This means that BBI shareholders requesting documents must do so by [                    ], 2018, in order to receive them before the special meeting.

You should rely only on the information contained in, or incorporated by reference into, this document. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this document. This document is dated [                    ], 2018, and you should assume that the information in this document is accurate only as of such date. You should assume that the information incorporated by reference into this document is accurate as of the date of such document. Neither the mailing of this document to BBI shareholders nor the issuance by Stifel of shares of common stock of Stifel in connection with the merger will create any implication to the contrary.

This document does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Except where the context otherwise indicates, information contained in this document regarding BBI has been provided by BBI, and information contained in this document regarding Stifel has been provided by Stifel.

Please see “Where You Can Find More Information,” beginning on page 99, for more details.

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS

The following are some questions that you may have about the merger and the special meeting, as well as brief answers to those questions. We urge you to read carefully the remainder of 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 or the special meeting. Additional important information is also contained in the documents incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information,” beginning on page 99.

Unless the context otherwise requires, references in this proxy statement/prospectus to “Stifel” refer to Stifel Financial Corp., a Delaware corporation; references to “BBI” refer to Business Bancshares, Inc., a Missouri corporation; references to “BBI Bank” refer to The Business Bank of St. Louis, a Missouri state-chartered bank and wholly owned subsidiary of BBI; and references to “we,” “our” or “us” refer to Stifel and BBI.

Upon completion of the merger, holders of common stock of BBI (which we refer to as “BBI common stock”), including both the common stock, $0.01 par value per share, of BBI (which we refer to as “BBI voting common stock”) and the non-voting common stock, $0.01 par value per share, of BBI (which we refer to as “BBI non-voting common stock”), will receive 0.705 shares of common stock, $0.15 par value per share, of Stifel (which we refer to as “Stifel common stock”) for each share of BBI common stock they hold immediately prior to the merger, plus cash in lieu of fractional shares. Based on the number of shares of Stifel common stock and BBI common stock outstanding as of the date of the merger agreement, current holders of BBI common stock (which we refer to as “BBI shareholders”) are expected to own up to approximately 3% of the outstanding Stifel common stock immediately following the merger (without giving effect to any shares of Stifel common stock held by BBI shareholders prior to the merger).

The merger cannot be completed unless, among other things, BBI shareholders approve the proposal (which we refer to as the “merger proposal”) to adopt and approve the merger agreement, the related plan of merger and the merger.

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This document is also a prospectus that is being delivered to BBI shareholders because, in connection with the merger, Stifel is offering shares of Stifel common stock to BBI shareholders.

This proxy statement/prospectus contains important information about the merger and important information to consider in connection with an investment in Stifel common stock. You should read it carefully and in its entirety. The enclosed materials allow you to have your shares of BBI voting common stock voted by proxy without attending the special meeting. Your vote is important, and we encourage you to submit your proxy as soon as possible.

Stock Options: At the effective time of the merger, each outstanding and unexercised option to purchase shares of BBI common stock (which we refer to as a “BBI stock option”) will become fully vested and automatically will be converted into the right to receive an amount in cash equal to $41.76 minus the exercise price per share of the option.

Restricted Stock: At the effective time of the merger, each outstanding award in respect of a share of BBI common stock that is subject to vesting, repurchase or other lapse restriction (which we refer to as “BBI restricted stock”) will fully vest and be cancelled and converted automatically into the right to receive the merger consideration (together with any accrued but unpaid dividends corresponding to the award).

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Adjournment proposal:

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If you plan to attend the special meeting, you must hold your shares in your own name or have proof of share ownership from the record holder of your shares, such as a recent brokerage statement or a letter confirming your ownership. In addition, you must bring a form of personal photo identification with you in order to be admitted to the special meeting. BBI reserves the right to refuse admittance to anyone without proper proof of share ownership or without proper photo identification. To ensure your representation at the special meeting, we urge you to complete, sign and date the enclosed proxy card and to return it promptly in the envelope provided whether or not you plan to attend the special meeting. Returning the proxy card will not affect your right to attend the special meeting and vote.

The U.S. federal income tax consequences described above may not apply to all holders of BBI common stock. We strongly urge you to consult your independent tax advisor for a full understanding of the

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application of U.S. federal income tax laws to your particular situation as well as any tax consequences arising under the U.S. federal estate or gift tax rules, or under the laws of any state, local, foreign or other taxing jurisdiction or under any applicable treaty.

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STIFEL SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA

The following Stifel selected historical consolidated financial data is provided to aid your analysis of the financial aspects of the merger. The information set forth below is only a summary and is not necessarily indicative of Stifel’s results of future operations. When you read this historical consolidated financial data, it is important that you also read Stifel’s historical consolidated financial statements and related notes, as well as the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” each included in Stifel’s Annual Report on Form 10-K for the year ended December 31, 2017, portions of which have been recast in Stifel’s Current Report on Form 8-K filed on June 19, 2018, which documents are incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information,” beginning on page 99.

The consolidated financial data of Stifel as of March 31, 2018, and for the three-month periods ended March 31, 2018 and 2017, have been derived from Stifel’s historical unaudited interim consolidated financial statements contained in its Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2018, which is incorporated by reference into this proxy statement/prospectus. In the opinion of Stifel’s management, the unaudited interim consolidated financial statements of Stifel have been prepared on the same basis as its audited consolidated financial statements and include all adjustments, consisting of normal recurring adjustments, necessary for a fair statement of the financial position of Stifel as of March 31, 2018, and its results of operations for the three-month periods ended March 31, 2018 and 2017. Results of interim periods are not necessarily indicative of the results expected for a full year or for future periods.

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Stifel’s Canadian subsidiary, Stifel Nicolaus Canada, Inc. (“SN Canada”), ceased business operations as of September 30, 2013. The results of SN Canada, previously reported in the Institutional Group segment, are classified as discontinued operations for all periods presented.

The following items should be considered when comparing the data from year to year: (i) the merger with KBW on February 15, 2013; (ii) the acquisitions of the U.S. institutional fixed income sales and trading business and the hiring of the European institutional fixed income sales and trading team from Knight Capital Group in July 2013; (iii) the expensing of stock awards issued as retention as part of the acquisitions of KBW and the Knight Capital fixed income business during 2013; (iv) the recognition of a U.S. tax benefit in connection with discontinuing the business operations of SN Canada in 2013; (v) the acquisitions of De La Rosa, & Co., Oriel Securities (which we refer to as “Oriel”) and 1919 Investment Counsel and the expensing of stock awards issued as retention as part of the Oriel and 1919 Investment Counsel acquisitions during 2014; (vi) the acquisitions of Sterne Agee Group, Inc. and Barclays Wealth and Investment Management (which we refer to as “Barclays”) during 2015; (vii) the acquisitions of Eaton Partners, LLC and ISM Capital LLP and the expensing of stock awards issued as retention as part of the Barclays acquisition during 2016; (viii) the acquisition of City Securities Corporation; (ix) the actions taken by Stifel and its subsidiaries in response to the Tax Cuts and Jobs Act (which we refer to as “tax legislation”) to maximize tax savings; (x) merger-related charges; (xi) litigation-related expenses associated with previously disclosed legal matters; (xii) the revaluation of the Stifel and its subsidiaries’ deferred tax assets as a result of the enacted tax legislation; and (xiii) the favorable impact of the adoption of new accounting guidance associated with stock-based compensation during 2017. See the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Stifel’s Current Report on Form 8-K filed on June 19, 2018, which is incorporated by reference into this proxy statement/prospectus, for a discussion of these items and other items that may affect the comparability of data from year to year. Please see “Where You Can Find More Information,” beginning on page 99.

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BBI SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA

The following table presents selected historical consolidated financial information and other financial data for BBI. The data for the three months ended March 31, 2018 and 2017, are derived from unaudited financial data of BBI. The consolidated financial data (except per share data) for the fiscal years ended, and as of, December 31, 2017, 2016, 2015, 2014 and 2013, are derived from audited consolidated financial statements of BBI. Operating results for prior periods are not necessarily indicative of the results that might be expected for 2018 or any future period, and results for the three-month periods ended March 31, 2018 and 2017, may not be indicative of the results that may be expected for the full fiscal year or future periods.

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COMPARATIVE HISTORICAL AND UNAUDITED PRO FORMA PER SHARE DATA

The following table sets forth, for the year ended December 31, 2017, and for the three months ended March 31, 2018, selected per share information for Stifel common stock on a historical and pro forma combined basis and for BBI common stock on a historical and pro forma equivalent basis. Except for the historical information as of and for the year ended December 31, 2017, the information provided in the table below is unaudited.

The pro forma information provided in the table below is for illustrative purposes only and is not necessarily an indication of the results that would have been achieved had the transaction been completed as of the dates indicated or that may be achieved in the future. The pro forma information also does not consider any integration expenses, expense efficiencies or other potential effects of the merger. The pro forma calculations reflect the issuance of 1,994,376 shares of Stifel common stock in the merger based upon 2,828,902 shares of BBI common stock outstanding as of the date of the merger agreement. The pro forma combined equivalent per share amounts are calculated by multiplying each pro forma combined per share amount by the exchange ratio.

You should read the data provided below with the historical consolidated financial statements and related notes of Stifel for the year ended December 31, 2017, contained in its Current Report on Form 8-K filed on June 19, 2018, and its Quarterly Report on Form 10-Q for the quarter ended March 31, 2018, which are incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information,” beginning on page 99.

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COMPARATIVE PER SHARE MARKET PRICE AND DIVIDEND INFORMATION

Comparative Price Information

Stifel common stock trades on the NYSE and the CHX under the symbol “SF.”

The following table sets forth the high, low and closing prices for Stifel common stock as reported on the NYSE on May 9, 2018, the last trading day before the date of the public announcement of the merger, and [                    ], 2018, the last practicable trading day before the date of this proxy statement/prospectus. The table also includes the market value of BBI common stock on an equivalent price per share basis, as determined by reference to the value of the merger consideration to be received in respect of each share of BBI common stock in the merger. These equivalent prices per share reflect the fluctuating value of the Stifel common stock that BBI shareholders would receive as the stock consideration for each share of BBI common stock if the merger was completed on either of these dates. Historical market value information regarding BBI common stock is not provided because there is no active trading market for BBI common stock.

The above table shows only historical comparisons. These comparisons may not provide meaningful information to BBI shareholders in determining whether to approve the merger proposal. BBI shareholders are urged to obtain current market quotations for Stifel common stock and to review carefully the other information contained in this proxy statement/prospectus or incorporated by reference into this proxy statement/prospectus, when considering whether to approve the merger proposal. Please see “Where You Can Find More Information,” beginning on page 99.

Stifel Market Price and Dividend Information

The following table shows, for the calendar quarters indicated, the high and low sale prices per share of Stifel common stock as reported on the NYSE and the cash dividends declared per share of Stifel common stock.

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Stifel did not pay cash dividends during 2016. During the third quarter of 2017, Stifel announced that its board of directors had authorized a dividend program under which Stifel intends to pay a regular quarterly cash dividend to holders of Stifel common stock. However, Stifel’s board of directors may change its dividend policy at any time, and no assurances can be given that dividends will continue to be paid by Stifel or the surviving corporation or that dividends, if paid, will not be reduced or eliminated in future periods. The payment of dividends on Stifel common stock is subject to several factors, including the determination and discretion of Stifel’s board of directors, operating results, financial requirements of Stifel and the availability of funds from its subsidiaries. See Note 19 of the Notes to Consolidated Financial Statements for the year ended December 31, 2017, included in Stifel’s Current Report on Form 8-K filed on June 19, 2018, for more information on the capital distribution restrictions placed on Stifel’s broker-dealer subsidiaries and Stifel Bank & Trust.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained or incorporated by reference into this proxy statement/prospectus may be deemed to be “forward-looking statements,” within the meaning of Section 27A of the Securities Act of 1933, as amended (which we refer to as the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (which we refer to as the “Exchange Act”), giving Stifel’s or BBI’s expectations or predictions of future financial or business performance or conditions. Forward-looking statements are typically identified by words such as “believe,” “expect,” “anticipate,” “intend,” “target,” “estimate,” “continue,” “positions,” “projections,” “prospects” or “potential,” by future conditional verbs such as “will,” “would,” “should,” “could” or “may” or by variations of such words or by similar expressions. Such forward-looking statements include, but are not limited to, statements about the benefits of the merger, including future financial and operating results of Stifel, BBI or the surviving corporation following the merger, Stifel’s and the surviving corporation’s plans, objectives, expectations and intentions, the expected timing of the completion of the merger, financing plans and the availability of capital, the likelihood of success and impact of litigation and other statements that are not historical facts. These statements are only predictions based on Stifel’s and BBI’s current expectations and projections about future events. Annualized, pro forma, projected and estimated numbers are used for illustrative purposes only, are not forecasts and may not reflect actual results.

Forward-looking statements involve inherent risks and uncertainties, and important factors could cause actual results to differ materially from those anticipated, including those factors discussed below under “Risk Factors,” beginning on page 24. In addition to factors previously disclosed in Stifel’s reports filed with the SEC, the following factors, among others, could cause actual results to differ materially from forward-looking statements:

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In addition, the timing and occurrence or non-occurrence of events may be subject to circumstances beyond Stifel’s or BBI’s control.

For any forward-looking statements made in this proxy statement/prospectus or in any documents incorporated by reference into this proxy statement/prospectus, Stifel and BBI claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. You are cautioned not to place undue reliance on these statements, which speak only as of the date of this proxy statement/prospectus or the date of the applicable document incorporated by reference into this proxy statement/prospectus. Except to the extent required by applicable law, Stifel and BBI do not undertake to update forward-looking statements to reflect facts, circumstances, assumptions or events that occur after the date the forward-looking statements are made. All written and oral forward-looking statements concerning the merger or other matters addressed in this proxy statement/prospectus and attributable to Stifel, BBI or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this proxy statement/prospectus.

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RISK FACTORS

In addition to general investment risks and the other information contained in or incorporated by reference into this proxy statement/prospectus, including the matters addressed under the section “Cautionary Statement Regarding Forward-Looking Statements,” beginning on page 22, you should carefully consider the following risk factors in deciding how to vote for the proposals presented in this proxy statement/prospectus. You should also consider the other information in this proxy statement/prospectus and the other documents incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information,” beginning on page 99.

Risks Related to the Merger and Stifel’s Business Upon Completion of the Merger

Because the market price of Stifel common stock will fluctuate, BBI shareholders cannot be certain of the market value of the merger consideration they will receive.

Upon completion of the merger, each share of BBI common stock issued and outstanding immediately prior to the effective time of the merger (except for shares held by BBI as treasury stock or by Stifel other than in a fiduciary or agency capacity or as a result of debts previously contracted, if any, and shares held by BBI shareholders who properly exercise their rights to dissent from the merger) will be converted into the right to receive 0.705 shares of Stifel common stock. The market value of the Stifel common stock to be received by BBI shareholders in the merger will vary from the closing price of Stifel common stock on the date Stifel and BBI announced the merger, on the date that this proxy statement/prospectus is mailed to BBI shareholders, on the date of the special meeting and on the date the merger is completed. Any change in the market price of Stifel common stock prior to the completion of the merger will affect the market value of the merger consideration that BBI shareholders will receive upon completion of the merger.

The market price of Stifel common stock could be subject to significant fluctuations due to changes in sentiment in the market regarding Stifel’s operations or business prospects, including market sentiment regarding Stifel’s entry into the merger agreement. Changes in the market price of Stifel common stock may also result from a variety of other factors, including the following, many of which are outside Stifel’s control:

Therefore, at the time of the special meeting, you will not know the precise market value of the consideration you will receive at the effective time of the merger. You should obtain current market quotations for shares of Stifel common stock before voting your shares at the special meeting.

In addition, BBI will not have the right to terminate the merger agreement due to a decline in the market price of Stifel common stock unless (i) both (a) the average closing price of Stifel common stock during a specified period before the effective time of the merger is less than $47.02, and (b) Stifel common stock

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underperforms the KBW NASDAQ Capital Market Index by more than 20%, and (ii) Stifel declines to make a compensating adjustment to the exchange ratio. Even if the conditions relating to Stifel common stock described in clause (i) of the preceding sentence exist, there can be no assurance that BBI will exercise BBI’s right to terminate the merger agreement, and BBI shareholders will have no right to vote on BBI’s decision whether to exercise that right. If BBI does exercise such right, there can be no assurance as to whether Stifel will decide to make a compensating adjustment to the exchange ratio.

The market price of Stifel common stock after the merger may be affected by factors different from those affecting the shares of BBI or Stifel currently.

Upon completion of the merger, holders of BBI common stock will become holders of Stifel common stock. Stifel’s business differs in important respects from that of BBI, and, accordingly, the results of operations of Stifel and the market price of Stifel common stock after the completion of the merger may be affected by factors different from those currently affecting the independent results of operations of each of Stifel and BBI. For a discussion of the business of Stifel and of certain factors to consider in connection with the business of Stifel, see the documents incorporated by reference into this proxy statement/prospectus and referred to under “Where You Can Find More Information,” beginning on page 99, including, in particular, the section titled “Risk Factors” in Stifel’s Annual Report on Form 10-K for the year ended December 31, 2017. For a discussion of the business of BBI, please see “Proposal No. 1: The Merger Proposal—Information About BBI” on page 85.

The fairness opinion delivered to the BBI board by FIG Partners prior to the signing of the merger agreement does not reflect any changes in circumstances that occur after the date of the opinion.

The opinion of FIG Partners as to the fairness from a financial point of view of the aggregate merger consideration to be received by the BBI shareholders in the merger, was delivered orally to the BBI board on May 9, 2018, before the BBI board approved the merger, and was subsequently confirmed in writing on May 10, 2018. The opinion speaks as of the time the opinion was rendered and does not speak as of the time the merger will be completed or as of any date other than the date of such opinion. Because BBI does not currently anticipate asking FIG Partners to update its opinion, the opinion will not address the fairness of the merger consideration from a financial point of view at the time the merger is completed. Accordingly, the opinion does not reflect any changes in circumstances that may occur after the date of the opinion. Changes in the operations and prospects of BBI or Stifel, general market and economic conditions and other factors that may be beyond the control of BBI and Stifel may alter the value of BBI or Stifel or the price of shares of Stifel common stock by the time the merger is completed. For a description of the opinion of FIG Partners, please refer to “Proposal No. 1: The Merger Proposal—The Merger—Opinion of FIG Partners, LLC,” beginning on page 9. For a description of the other factors considered by the BBI board and Stifel’s board of directors in deciding to approve the merger agreement, the related plan of merger and the merger, please refer to “Proposal No. 1: The Merger Proposal—The Merger—Stifel’s Reasons for the Merger,” beginning on page 50, and “Proposal No. 1: The Merger Proposal—The Merger—BBI’s Reasons for the Merger and Recommendation of the BBI Board,” beginning on page 41.

Regulatory approvals may not be received, may take longer than expected or may impose conditions that are not presently anticipated or that could have an adverse effect on Stifel and/or the surviving corporation following the merger.

Before the merger may be completed, Stifel and BBI must obtain approval from the Federal Reserve Board, and the Commissioner of Finance must issue an order declaring Stifel’s acquisition of BBI lawful under the Missouri bank holding company act. Other approvals, waivers or consents from regulators may also be required. In determining whether to grant these approvals, the regulators consider a variety of factors, including the regulatory standing of each party and the factors described under “Proposal No. 1: The Merger Proposal—The Merger—Regulatory Approvals Required for the Merger.” An adverse development in either party’s regulatory standing or an adverse finding under any of these factors could result in an inability to obtain approval or could delay the receipt of approval. In addition, regulators may impose conditions on the completion of the merger or

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require changes to the terms of the merger. Such conditions or changes could have the effect of delaying or preventing completion of the merger or imposing additional costs on or limiting the revenues of Stifel and/or the surviving corporation following the merger, any of which could have an adverse effect on Stifel and/or the surviving corporation following the merger. Stifel is not obligated to complete the merger if the regulatory approvals received in connection with the merger impose any burdensome condition (as such term is defined in the merger agreement) upon Stifel following the merger. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Conditions to Complete the Merger.”

The Federal Reserve Board has stated that if material weaknesses of an applicant or target banking organization are identified by examiners while an expansionary application is under review by the agency, the Federal Reserve Board will not allow the application to remain pending while the banking organization addresses any identified weaknesses. The Federal Reserve Board will require the applicant banking organization to withdraw its application pending resolution of any supervisory concerns. Based on the foregoing, if there is an adverse development in either party’s regulatory standing, Stifel may be required to withdraw its application with the Federal Reserve Board and, if possible, resubmit it after the applicable supervisory concerns have been resolved.

Integrating Stifel and BBI may be more difficult, costly or time consuming than expected, and the anticipated benefits and cost savings of the merger may not be realized.

Stifel and BBI have operated, and, until the completion of the merger, will continue to operate, independently. The success of the merger, including anticipated benefits and cost savings, will depend, in part, on Stifel’s ability to successfully integrate the businesses of Stifel and BBI in a manner that permits growth opportunities and does not materially disrupt BBI’s existing customer and employee relationships nor result in decreased revenues due to loss of customers. It is possible that the integration process could result in the loss of key employees, the disruption of either company’s ongoing businesses or inconsistencies in standards, controls, procedures and policies that adversely affect Stifel’s and the surviving corporation’s ability to maintain relationships with clients, customers, depositors and employees or to achieve the anticipated benefits and cost savings of the merger. The loss of key employees could adversely affect Stifel’s ability to successfully conduct its business, which could have an adverse effect on Stifel’s financial results and the value of Stifel common stock. If Stifel experiences difficulties with the integration process, the anticipated benefits of the merger may not be realized fully or at all or may take longer to realize than expected. As with any merger of financial institutions, there also may be business disruptions that cause Stifel and/or BBI to lose customers or cause customers to remove their accounts from Stifel and/or BBI and move their business to competing financial institutions. Integration efforts between the two companies will also divert management attention and resources. These integration matters could have an adverse effect on each of BBI and Stifel during this transition period and for an undetermined period after completion of the merger on Stifel and/or the surviving corporation. In addition, the actual cost savings of the merger could be less than anticipated.

Stifel and/or the surviving corporation may be unable to retain Stifel and/or BBI personnel successfully after the merger is completed.

The success of the merger will depend in part on Stifel’s and the surviving corporation’s ability to retain the talents and dedication of key employees currently employed by Stifel and BBI. It is possible that these employees may decide not to remain with Stifel or BBI, as applicable, while the merger is pending or with Stifel or the surviving corporation after the merger is consummated. If key employees terminate their employment, or if an insufficient number of employees is retained to maintain effective operations, Stifel’s or the surviving corporation’s business activities may be adversely affected, and management’s attention may be diverted from successfully integrating BBI to hiring suitable replacements, all of which may cause Stifel’s and the surviving corporation’s business to suffer. In addition, Stifel and BBI may not be able to locate suitable replacements for any key employees who leave either company or to offer employment to potential replacements on reasonable terms.

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Certain of BBI’s directors and executive officers have interests in the merger that may differ from the interests of BBI shareholders.

BBI shareholders should be aware that some of BBI’s directors and executive officers have interests in the merger and have arrangements that are different from, or in addition to, those of BBI shareholders generally. These interests include, among others, the treatment of outstanding BBI equity-based awards pursuant to the merger agreement, certain payments and benefits payable under compensation agreements entered into with executive officers, including new employment continuation agreements entered into between Stifel and each BBI executive officer providing for continuing employment with BBI Bank following completion of the merger, and rights to ongoing indemnification and insurance coverage by Stifel and the surviving corporation for acts or omissions occurring prior to the merger. The BBI board was aware of these interests and considered these interests, among other matters, when making its decision to approve the merger agreement, the related plan of merger and the merger and in recommending that BBI shareholders vote in favor of approving the merger proposal.

For a more complete description of these interests, please see “Proposal No. 1: The Merger Proposal—The Merger—Interests of Certain Persons in the Merger,” beginning on page 52.

The merger is subject to certain closing conditions that, if not satisfied or waived, may result in the merger agreement being terminated, which could negatively impact BBI or Stifel.

The merger is subject to customary conditions that must be satisfied (or waived, to the extent permitted by law) in order for the merger to be completed, including the receipt of the requisite approval of the merger proposal by the BBI shareholders, the receipt of the requisite regulatory approvals and expiration or termination of all statutory waiting periods in respect thereof, the receipt of continuation agreements from the requisite number of BBI Bank employees, BBI’s satisfaction of certain financial conditions with respect to loans, deposits, non-performing assets and tangible common equity and the termination of BBI’s existing credit facility with Associated Bank, N.A. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Conditions to Complete the Merger,” beginning on page 78, for a more complete discussion of the conditions to completion of the merger.

Various factors could cause BBI to fail to satisfy one or more of the conditions to Stifel’s obligations to complete the merger described above, and, accordingly, the merger may not be completed. For example, BBI may fail to retain a sufficient number of the employees that it is required to retain pursuant to continuation agreements due to factors such as competition for bank executive talent, uncertainty regarding employees’ roles in the surviving corporation and personal and family motivations. In addition, BBI may fail to meet the financial conditions set forth in the merger agreement due to factors such as reputational damage, adverse economic conditions, liquidity and capital risks, credit rating downgrades, retention of qualified personnel, market risk, counterparty and borrower credit risks, changes in interest rates, competition, legal, regulatory, operational and compliance risks, dependence on technology, security risks, shortcomings in financial controls and risk management, along with various other factors that may result in BBI having slower growth, more non-performing assets or weaker results of operation than it currently anticipates.

The merger agreement may be terminated by either party under certain circumstances, including if the merger is not consummated by March 31, 2019, and the parties can mutually decide to terminate the merger agreement, at any time prior to the effective time of the merger, even if the merger proposal has already been approved by the BBI shareholders. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Termination of the Merger Agreement,” beginning on page 80, for a more complete discussion of the circumstances in which the merger agreement may be terminated.

If the merger agreement is terminated, there may be various consequences. For example, BBI’s or Stifel’s businesses may be impacted adversely by the failure to pursue other beneficial opportunities due to the focus of

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management on the merger, without realizing any of the anticipated benefits of completing the merger, or the price of Stifel common stock could decline to the extent that the current price reflects a market assumption that the merger will be completed. If the merger agreement is terminated and the BBI board seeks another merger or business combination, BBI shareholders cannot be certain that BBI will be able to find a party willing to pay equivalent or greater consideration than that which Stifel has agreed to pay in the merger. If the merger agreement is terminated under certain circumstances, BBI may be required to pay to Stifel a termination fee of $5.75 million. For a more complete description of this termination fee, please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Termination Fee” on page 81.

BBI will be subject to business uncertainties and contractual restrictions while the merger is pending.

Uncertainty about the effect of the merger on employees and customers may have an adverse effect on BBI. These uncertainties may impair BBI’s ability to attract, retain and motivate key personnel until the merger is completed and could cause customers and others that deal with BBI to seek to change existing business relationships with BBI. Retention of certain employees by BBI may be challenging while the merger is pending, as certain employees may experience uncertainty about their future roles with Stifel or the surviving corporation. If key employees depart because of issues relating to the uncertainty and difficulty of integration, or a desire not to remain with BBI, BBI’s business could be harmed. In addition, subject to certain exceptions, BBI has agreed in the merger agreement to operate its business in the ordinary course prior to closing and to not take certain specified actions without Stifel’s consent. These restrictions may prevent BBI from pursuing attractive business opportunities that may arise prior to the completion of the merger. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Covenants and Agreements—Conduct of Businesses Prior to the Closing of the Merger” on page 70 for a description of the restrictive covenants applicable to BBI.

If the merger is not completed, Stifel and BBI will have incurred substantial expenses without realizing the expected benefits of the merger and may experience negative reactions to the termination of the merger from third parties.

Each of Stifel and BBI has incurred and will incur substantial expenses in connection with the negotiation and completion of the transactions contemplated by the merger agreement, as well as the costs and expenses of filing, printing and mailing this proxy statement/prospectus, and all filing and other fees paid to the SEC in connection with the merger. If the merger is not completed, Stifel and BBI will have to recognize these expenses without realizing the expected benefits of the merger. In addition, if the merger is not completed, Stifel and/or BBI may experience negative reactions to the termination of the merger from customers, depositors, investors, vendors and others.

The merger agreement limits BBI’s ability to pursue acquisition proposals and requires BBI to pay a termination fee of  $5.75 million under certain circumstances, including circumstances involving alternative acquisition proposals. In addition, certain provisions of the Stifel and BBI charters and bylaws may deter potential acquirers.

The merger agreement contains non-solicitation provisions that, subject to limited exceptions, prohibit BBI and its representatives from initiating, soliciting, knowingly inducing or encouraging or knowingly facilitating the making of any offers with respect to, and from engaging or participating in negotiations with any person concerning, any competing acquisition proposals. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Agreement Not to Solicit Other Offers” on page 76 for further information. The merger agreement also provides that BBI will be required to pay a termination fee in the amount of $5.75 million in the event that the merger agreement is terminated under certain circumstances, including circumstances involving a competing acquisition proposal. Please see “Proposal No. 1: The Merger Proposal—The Merger Agreement—Termination Fee.” These provisions might discourage a potential competing acquirer that might have an interest in acquiring all or a significant part of BBI from considering or proposing such an acquisition.

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Under the General Corporation Law of the State of Delaware (which we refer to as the “DGCL”), certain business combinations involving affiliates or interested stockholders of Stifel require the approval of Stifel’s board of directors and disinterested shareholders holding two-thirds of the outstanding shares of Stifel common stock unless certain other requirements are met. Please see “Comparison of Shareholder Rights—Restrictions on Business Combinations.” These provisions and other provisions of the BBI and Stifel charters and bylaws, including provisions regarding Stifel’s partially classified board of directors, described under “Comparison of Shareholder Rights—Number of Directors; Classification,” or of the DGCL or the MGBCL could make it more difficult for a third party to acquire control of BBI or Stifel and may discourage a potential competing acquirer.

The shares of Stifel common stock to be received by BBI shareholders as a result of the merger will have different rights from shares of BBI common stock.

Upon completion of the merger, BBI shareholders will become holders of Stifel common stock, and their rights as holders of Stifel common stock will be governed by the DGCL and the Stifel charter and bylaws. The rights associated with BBI common stock are different from the rights associated with Stifel common stock. Please see “Comparison of Shareholder Rights,” beginning on page 90, for a discussion of the different rights associated with Stifel common stock.

BBI shareholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management.

BBI shareholders currently have the right to vote in the election of the BBI board and on other matters requiring shareholder approval under the MGBCL and BBI’s charter and bylaws. Upon completion of the merger, each BBI shareholder who receives shares of Stifel common stock will become a shareholder of Stifel, with a percentage ownership of Stifel that is much smaller than the shareholder’s percentage ownership of BBI. BBI shareholders collectively will receive up to approximately 2.0 million shares of Stifel common stock in the merger. Based on the number of shares of Stifel common stock and BBI common stock outstanding as of the date of the merger agreement, current BBI shareholders are expected to own up to approximately 3% of the outstanding Stifel common stock immediately following the merger (without giving effect to any shares of Stifel common stock held by BBI shareholders prior to the merger). Because of this, BBI shareholders will have less influence on the management and policies of Stifel than they now have on the management and policies of BBI.

If the merger does not constitute a “reorganization” under Section 368(a) of the Code, then each holder of BBI common stock may be responsible for payment of U.S. federal income taxes related to the merger.

If BBI shareholders elect to exercise dissenters’ rights with respect to a material number of shares of BBI common stock, we may not be able to receive the requisite tax opinions to the effect that the merger qualifies as a “reorganization” within the meaning of section 368(a) of the Code, and the merger may not be completed due to the failure of a required closing condition or may need to be restructured. For purposes of rendering the tax opinions, a material number of shares may be 20% of the outstanding shares of BBI common stock or fewer depending on the amount of cash that BBI shareholders otherwise receive in connection with the merger. The tax opinions are not binding on the Internal Revenue Service (which we refer to as the “IRS”) or on any court. Whether or not tax opinions are received, if the merger is completed but fails to qualify as a “reorganization” under Section 368(a) of the Code, then each holder of shares of BBI common stock would recognize a gain or loss equal to the difference between (i) the sum of the fair market value of the Stifel common stock and cash, if any, received by the holder in the merger, and (ii) the holder’s adjusted tax basis in the shares of BBI common stock exchanged therefor. The likely U.S. federal income tax liability in such event will not be known until the effective time of the merger, as the aggregate value of the Stifel common stock to be received by each holder of BBI common stock will fluctuate with the market price of Stifel common stock.

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Risks Relating to Stifel’s Business

You should read and consider risk factors specific to Stifel’s business that will also affect Stifel and the surviving corporation after the merger. These risks are described in the sections titled “Risk Factors” in Stifel’s Annual Report on Form 10-K for the year ended December 31, 2017, and in other documents incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information,” beginning on page 99, for the location of information incorporated by reference into this proxy statement/prospectus.

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THE SPECIAL MEETING

General

This proxy statement/prospectus is being provided to BBI shareholders as part of a solicitation of proxies by the BBI board for use at the special meeting and at any adjournments or postponements of such meeting. The date of this proxy statement/prospectus is [            ], 2018, and it is first being mailed or otherwise delivered to BBI shareholders on or about [            ], 2018. This proxy statement/prospectus provides BBI shareholders with important information about the special meeting and should be read carefully and in its entirety.

Date, Time and Place of Meeting

The special meeting is scheduled to be held as follows:

Date: [            ], 2018

Time: 8:00 a.m. local time

Place: BBI’s corporate office at 8000 Maryland Ave., 14th Floor Boardroom, Clayton, Missouri 63105

Purposes of the Special Meeting

The special meeting is for the holders of BBI voting common stock to consider and vote on the following proposals:

Recommendation of the BBI Board

The BBI board unanimously recommends that holders of BBI voting common stock vote:

The BBI board unanimously approved the merger agreement, the related plan of merger and the merger. Please see “Proposal No. 1: The Merger Proposal—The Merger—BBI’s Reasons for the Merger and Recommendation of the BBI Board,” beginning on page 41.

In considering the recommendation of the BBI board with respect to the merger, BBI shareholders should be aware that some of the BBI directors and executive officers may have interests that are different from, or in addition to, the interests of BBI shareholders generally. Please see “Proposal No. 1: The Merger Proposal—The Merger—Interests of Certain Persons in the Merger,” beginning on page 52.

Record Date for the Special Meeting; Stock Entitled to Vote

Only holders of record of BBI voting common stock at the close of business on [            ], 2018, which is the record date for the special meeting, are entitled to receive notice of and to vote at the special meeting. On the record date, [            ] shares of BBI voting common stock were issued, outstanding and eligible to vote at the special meeting. Each holder of record of BBI voting common stock is entitled to cast one vote for each share held in that holder’s name on BBI’s books as of the record date for the special meeting on each matter being submitted for approval by the holders of BBI voting common stock at the special meeting.

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Quorum

The presence at the special meeting, in person or by proxy, of holders of a majority of the outstanding shares of BBI common stock entitled to vote at the special meeting pursuant to the BBI charter will constitute a quorum for the transaction of business. Abstentions and broker non-votes that are otherwise properly represented at the special meeting will be included in determining the number of shares present at the special meeting for the purpose of determining the presence of a quorum. If there is no quorum at the special meeting, the affirmative vote of a majority of the outstanding shares of BBI common stock entitled to vote at the special meeting and present at the special meeting, in person or by proxy, may adjourn the special meeting to a later date or dates.

Votes Required; Treatment of Abstentions

The votes required for each proposal are as follows:

An abstention occurs when a holder of BBI voting common stock attends the special meeting in person but abstains from voting or returns a signed proxy card with the “ABSTAIN” box marked. For the merger proposal and the adjournment proposal, an abstention will have the same effect as a vote cast “AGAINST” the proposal.

Voting Your Shares

General Directions

You may vote “FOR,” “AGAINST” or “ABSTAIN” with respect to each of the proposals presented at the special meeting. To ensure your representation at the special meeting, we urge you to complete, sign and date the enclosed proxy card and to return it promptly, whether or not you plan to attend the special meeting. Returning the proxy card will not affect your right to attend the special meeting and vote.

If you hold your shares in certificate or registered book-entry form and wish to vote in person, simply attend the special meeting (even if you have already voted by proxy), and you will be given a ballot when you arrive. See “—Shares Held in Street Name; Treatment of Broker Non-Votes” below for information regarding voting and attendance at the special meeting specific to BBI shareholders who hold their shares of BBI common stock in “street name” (that is, through a broker, bank or other nominee).

Submitting Proxies

To vote using the proxy card included with this proxy statement/prospectus, simply complete, sign and date the proxy card and return it promptly in the postage-paid return envelope provided , in accordance with the instructions on the proxy card. If you properly fill in your proxy card and send it to us in time, your “proxy” (the individual named on your proxy card) will vote your shares as you have directed. If you sign the proxy card but do not make specific choices, your proxy will vote your shares as recommended by the BBI board as follows:

If any other matter is properly presented, your proxy will use the proxy’s own judgment to determine how to vote. We are not aware of any other such matter to be acted on at the special meeting.

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Revoking Proxies

Holders of BBI voting common stock who hold their shares in certificate or registered book-entry form may revoke their proxies or change their vote at any time before the time their proxies are voted at the special meeting by: (i) signing and returning a proxy card with a later date; (ii) attending the special meeting in person, notifying BBI’s corporate secretary and voting by ballot at the special meeting; or (iii) delivering a written revocation letter to BBI’s corporate secretary. Attendance at the special meeting will not, in and of itself, constitute a revocation of a proxy. Subject to such revocation, shares represented by a properly executed proxy received in time for the special meeting will be voted by the proxy holder thereof in accordance with the instructions on the proxy.

Written notices of proxy revocations must be sent so that they will be received before the taking of the vote at the special meeting and should be addressed to:

Business Bancshares, Inc.

David Gamache, Corporate Secretary

8000 Maryland Ave, Suite 100

Clayton, Missouri 63105

If you hold your shares in “street name” and have instructed your broker, bank or other nominee to vote your shares, you must follow directions received from the broker, bank or other nominee in order to revoke or change those instructions.

Shares Held in Street Name; Treatment of Broker Non-Votes

If you hold your shares of BBI common stock in street name, you must vote your shares through your broker, bank or other nominee. You should receive a form from your broker, bank or other nominee asking how you want to vote your shares. Follow the directions on that form to give voting instructions to your broker, bank or other nominee. Under the rules that govern brokers, banks and other nominees who are voting with respect to shares held in street name, brokers, banks and other nominees have the discretion to vote such shares on routine matters but not on non-routine matters without specific instructions from the beneficial owner. At the special meeting, none of the matters is a routine matter. Therefore, if you fail to instruct your broker, bank or other nominee as to how to vote your shares of BBI voting common stock, your broker, bank or other nominee may not vote your shares on either of the proposals set forth in this proxy statement/prospectus, including the merger proposal.

If you plan to attend the special meeting, you will need to have proof of share ownership from the record holder of your shares, such as a recent brokerage statement or a letter confirming your ownership. You will also need to obtain a “legal proxy,” executed in your favor, from your broker, bank or other nominee to enable you to vote in person at the special meeting.

A “broker non-vote” occurs when a broker, bank or other nominee does not vote on a particular proposal because the broker does not receive instructions from the beneficial owner and does not have discretionary authority. A broker non-vote with respect to the merger proposal will have the same effect as a vote “AGAINST” the proposal. A broker non-vote with respect to the adjournment proposal will not be included in determining the number of shares present at the special meeting with respect to the adjournment proposal and, therefore, will have no effect on the vote on the adjournment proposal. It is VERY IMPORTANT that you return the instructions to your broker, bank or other nominee. If you wish to be represented, you must vote by completing and sending in or otherwise transmitting the information that is sent to you by your broker, bank or other nominee.

Dissenters’ Rights

Holders of BBI common stock are entitled to assert dissenters’ rights with respect to the merger proposal. These dissenters’ rights are conditioned on strict compliance with the requirements of Section 351.455 of the

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MGBCL. Please see “Proposal No. 1: The Merger Proposal—The Merger—Dissenters’ Rights,” beginning on page 58, and the full text of Section 351.455 of the MGBCL, which is reproduced in full in Annex C to this proxy statement/prospectus, for additional information.

Solicitation of Proxies

The BBI board is soliciting the proxies for the special meeting. Under the terms of the merger agreement, the costs and expenses of printing and mailing this proxy statement/prospectus will be borne equally by Stifel and BBI, and all filing and other fees paid to the SEC in connection with the merger will be borne by Stifel, with all other costs and expenses incurred in connection with the merger agreement and the transactions contemplated by the merger agreement paid by the party incurring the expense. In addition to solicitation by mail, BBI’s directors, officers and employees may also solicit proxies from shareholders personally and by telephone. BBI will not pay any additional or special compensation to these directors, officers or employees for these activities but may reimburse them for reasonable out-of-pocket expenses.

If BBI’s management deems it advisable, the services of individuals or companies that are not regularly employed by BBI may be used in connection with the solicitation of proxies. BBI does not presently intend to utilize the services of a proxy solicitation firm to assist in the solicitation of proxies for the special meeting but may decide to do so in the interests of time if circumstances warrant.

Delivery of Proxy Materials to BBI Shareholders Sharing an Address

Only one copy of this proxy statement/prospectus is being delivered to multiple BBI shareholders sharing an address, unless BBI has previously received contrary instructions from one or more of such shareholders. This is referred to as “householding.” BBI shareholders who hold their shares in “street name” can request further information on householding through their brokers, banks or other nominees. BBI shareholders may request that a separate copy of this proxy statement/prospectus be sent to a shared address to which a single copy of the document has been delivered by contacting Business Bancshares, Inc., David Gamache, Corporate Secretary, 8000 Maryland Ave., Suite 100, Clayton, Missouri 63105, or contacting Mr. Gamache by telephone, at (314) 721-8003.

Assistance

If you are a BBI shareholder and have any questions concerning the merger or this proxy statement/prospectus, would like additional copies of this proxy statement/prospectus or need help voting your shares of BBI voting common stock, please contact BBI’s corporate secretary, David Gamache, at (314) 721-8003.

Shares of BBI Voting Common Stock Held By Directors and Executive Officers and Certain Other Beneficial Owners; Voting Agreements

The following table sets forth, as of the record date for the special meeting, the beneficial ownership of BBI voting common stock by each of BBI’s directors and executive officers, by BBI’s directors and executive officers as a group and by each person or entity known by BBI to beneficially own more than 5% of the outstanding BBI voting common stock. Unless otherwise specified, the address of each listed BBI shareholder is c/o Business Bancshares, Inc., 8000 Maryland Avenue, Suite 100, Clayton, Missouri 63105.

The percentages of beneficial ownership in the following table are calculated in relation to the [            ] shares of BBI voting common stock that were issued and outstanding as of the record date for the special meeting. Beneficial ownership is determined in accordance with the rules of the SEC, which generally attribute beneficial ownership of securities to persons who possess sole or shared voting or investment power with respect to those securities, as well as shares issuable in connection with options exercisable within 60 days of the record date for the special meeting. Unless otherwise indicated, and subject to the voting agreements

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entered into with Stifel in connection with entering into the merger agreement, to BBI’s knowledge, the persons or entities identified in the table below have sole voting and investment power with respect to all shares shown as beneficially owned by them.

Pursuant to voting agreements more fully described under “Proposal No. 1: The Merger Proposal—The Merger Agreement—Director, Executive Officer and Large Shareholder Voting Agreements,” beginning on page

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82, each of BBI’s directors and executive officers and Castle Creek entered into separate written agreements in which they collectively agreed, among other things, to vote their shares of BBI voting common stock for the approval of the merger proposal. A copy of the form of voting agreement separately executed by each of BBI’s directors and executive officers and Castle Creek is attached as Exhibit A to the merger agreement, a copy of which is attached as Annex A to this proxy statement/prospectus and is incorporated herein by reference. As of the record date for the special meeting, the members of the BBI board, BBI’s executive officers and Castle Creek beneficially owned, in the aggregate, approximately 930,000 shares of BBI voting common stock (not including vested option shares), or approximately [    ]% of the outstanding BBI voting common stock.

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PROPOSAL NO. 1

THE MERGER PROPOSAL

THE MERGER

The following discussion contains certain information about the merger. The discussion is subject, and qualified in its entirety by reference, to the merger agreement attached as Annex A to this proxy statement/prospectus and incorporated herein by reference. We urge you to read carefully this entire proxy statement/prospectus, including “—The Merger Agreement,” beginning on page 66, for additional and more detailed information regarding the legal documents that govern the merger, including information about conditions to the completion of the merger and provisions for terminating or amending the merger agreement, and the merger agreement attached as Annex A for a more complete understanding of the merger.

General

Stifel and BBI are proposing a transaction in which Stifel will acquire BBI such that BBI will become a wholly owned subsidiary of Stifel and will remain the direct holding company for BBI Bank. This transaction is governed by the merger agreement, a copy of which is attached as Annex A to this proxy statement/prospectus. The merger agreement was unanimously approved by both Stifel’s board of directors and the BBI board. Stifel and BBI expect to complete the merger in the third or fourth quarter of 2018. However, neither Stifel nor BBI can assure you of when or if the merger will be completed. BBI must obtain the approval of holders of BBI voting common stock to approve the merger proposal at the special meeting, and both Stifel and BBI must obtain necessary regulatory approvals in addition to satisfying certain other closing conditions.

Terms of the Merger

The merger agreement provides that Merger Sub will merge with and into BBI, with BBI as the surviving corporation and becoming a wholly owned subsidiary of Stifel. BBI’s wholly owned bank subsidiary, BBI Bank, will be a wholly owned subsidiary of BBI and an indirect wholly owned subsidiary of Stifel.

In the merger, each share of BBI common stock issued and outstanding immediately prior to the completion of the merger, except for shares of BBI common stock held by BBI as treasury stock, certain shares held by Stifel, if any, and shares held by BBI shareholders who properly exercise their rights to dissent from the merger, will be converted into the right to receive 0.705 shares of Stifel common stock. No fractional shares of Stifel common stock will be issued in connection with the merger. Instead, holders of BBI common stock that would otherwise be entitled to receive a fractional share of Stifel common stock will receive cash in lieu thereof.

Background of the Merger

From time to time, the BBI board, BBI Bank’s board of directors and the BBI executive management team assess the economic, regulatory and competitive conditions in which BBI operates, as well as its long-term business strategy and objectives. The BBI board and BBI executive management team have periodically explored and discussed strategic options available to BBI for maintaining its competitiveness and increasing shareholder value. Among other things, these discussions have included the possibility of continuing to operate as an independent bank holding company, as well as potential strategic alternatives available to BBI, including acquisitions or business combinations involving other financial institutions.

In connection with BBI’s regular and ongoing evaluation of strategic alternatives, members of BBI management and of the BBI board have had discussions, from time to time, with representatives of other financial institutions about possible transactions and have regularly updated the BBI board regarding such discussions. In late 2017, BBI decided to consult with investment banking firms to discuss the banking industry

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in general and potential strategic alternatives that might be considered by BBI, including the potential sale of BBI. The BBI board invited two investment banking firms that were highly experienced in the commercial banking industry, one of which was KBW, a subsidiary of Stifel, to meet with the BBI board. At a meeting of the BBI board on December 19, 2017, KBW, among other things, discussed its credentials advising banks on strategic transactions such as mergers and acquisitions and provided preliminary feedback regarding BBI’s evaluation of potential strategic alternatives. The other investment banking firm discussed similar matters with the BBI board on December 18, 2017. On December 19, 2017, the BBI board decided to engage KBW as its financial advisor, and BBI management subsequently interviewed a number of law firms to represent BBI in any business combination transaction, ultimately recommending the retention of Lewis Rice LLC (which we sometimes refer to as “Lewis Rice”). In early February 2018, BBI and KBW executed an engagement letter regarding KBW’s role as a financial advisor to BBI in connection with a sale of BBI.

In consultation with BBI management, the KBW representatives working on the BBI engagement (which we sometimes refer to collectively as the “BBI KBW team”) compiled a list of 22 prospective acquirers, including Stifel, KBW’s parent company. That list was provided to BBI management on February 14, 2018, and the BBI KBW team reviewed the list of 22 prospective acquirers with the BBI board at a board meeting held the same day. The BBI board instructed the BBI KBW team to contact all of the companies on the list to solicit interest in a potential acquisition of BBI.

Also during February 2018, a confidential information memorandum containing initial, summary information about BBI and its business (which we refer to as the “confidential information memorandum”) was jointly compiled by the BBI KBW team and BBI management. In late February and early March 2018, in accordance with the directives of the BBI board, the BBI KBW team began reaching out to prospective acquirers regarding their willingness to enter into non-disclosure agreements to evaluate a potential acquisition candidate. Stifel entered into a non-disclosure agreement with BBI on February 21, 2018, and the BBI KBW team sent a copy of the confidential information memorandum to Christopher Reichert, the chief executive officer of Stifel Bank & Trust, Stifel’s bank subsidiary, on March 1, 2018. Six prospective acquirers, including Stifel, ultimately entered into non-disclosure agreements with BBI and received copies of the confidential information memorandum. Beginning on March 1, 2018, Stifel and five other prospective acquirers received access to an online data room to facilitate the prospective acquirers’ due diligence investigations of BBI. Preliminary meetings between BBI management and four of the prospective acquirers subsequently took place, including a meeting on March 6, 2018, between Mr. Kirby and other executive officers of BBI and Mr. Reichert and other Stifel representatives.

After this preliminary meeting between BBI management and Stifel, as it became apparent that Stifel was among the most interested prospective acquirers, and after BBI consulted with Lewis Rice, BBI and KBW agreed to modify the engagement letter between BBI and KBW to address conflicts of interest that could arise in connection with KBW’s role as financial advisor to BBI if KBW’s parent company, Stifel, became a bidder. On March 14, 2018, BBI and KBW entered into an amended engagement letter. Under the amended engagement letter, BBI and KBW agreed that KBW would continue to act as BBI’s financial advisor, including in connection with a potential sale of BBI to Stifel, but would not be requested or required to provide a fairness opinion in connection with any transaction between BBI and Stifel. KBW agreed to establish internal information barriers between the BBI KBW team and all other Stifel personnel who were working on behalf of Stifel in connection with its potential acquisition of BBI, including any personnel of KBW working on behalf of Stifel in connection with the potential acquisition (which we sometimes refer to as the “Stifel KBW team”), in order to manage and coordinate the sharing and use of information obtained from BBI or Stifel. BBI agreed to waive any actual or potential conflicts of interest that might arise or result or might have arisen or resulted from KBW’s provision of investment banking and financial advisory services to BBI in connection with a transaction with Stifel and also agreed to waive any claims against KBW relating to such conflicts. The amendment also provided that nothing in the amendment limited or reduced the obligation of the BBI KBW team to perform in good faith the investment banking and financial advisory services provided for in the engagement letter. The amendment also provided that BBI, in its sole discretion, could retain other advisors in connection with any transaction with Stifel and that the

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fees payable to KBW under the engagement letter would be reduced up to $250,000 by any fees and expenses BBI incurred in engaging another financial advisor and in obtaining a fairness opinion. In connection with this amendment to KBW’s engagement letter, KBW established an electronic data wall whereby access to the BBI KBW team’s electronic files related to the BBI engagement was limited to the members of the BBI KBW team, and no other Stifel personnel (whether on the Stifel KBW team or otherwise) were permitted to access those electronic files. KBW also communicated to Mr. Reichert and other Stifel representatives, including the Stifel KBW team, compliance guidance that included a requirement that Mr. Kirby or his designee be involved in any direct communications between the BBI KBW team and Stifel regarding the proposed merger and a requirement that the respective members of the BBI KBW and Stifel KBW teams not share with each other any information regarding the potential acquisition unless explicitly authorized by their respective clients.

On March 21, 2018, at the direction of BBI, the BBI KBW team communicated bidding instructions to the prospective acquirers, including Stifel. BBI set April 2, 2018, as the deadline for initial, non-binding interest letters or offers to be received by Larry Kirby, the chief executive officer of BBI. Two prospective acquirers submitted indications of interest: Stifel and Company A.

On April 4, 2018, the BBI board held a special meeting, with members of the BBI KBW team present, to review the proposal from each bidder. Stifel’s proposed price per share of BBI common stock was greater than the high end of Company A’s proposed price per share. In addition, the proposed merger consideration in Stifel’s proposal consisted entirely of Stifel common stock, while Company A’s proposal contemplated merger consideration that consisted of both Company A common stock and cash. The BBI board discussed each of the proposals, including the financial and tax consequences associated with each proposal, the respective financial performance and condition of each of Stifel and Company A, the strategic and cultural fit of BBI with each of Stifel and Company A and the execution risk of a merger with each of Stifel and Company A. The BBI board determined that the transaction proposed by Stifel represented an overall better strategic and cultural fit than Company A’s proposal, with lower execution risk, but that an increase in the merger consideration to be provided by Stifel should be proposed by BBI. The BBI board instructed the BBI KBW team to respond to Stifel with a counterproposal seeking a fixed exchange ratio of the number of shares of Stifel common stock for which each share of BBI common stock would be exchanged, subject to renegotiation if the price per share of Stifel common stock was outside a specified range prior to the execution of the merger agreement as a means of ensuring that the implied value of BBI common stock in the merger would be commensurate with the overall financial market at signing.

Following the BBI board’s special meeting, the BBI KBW team, together with other representatives of BBI, contacted representatives of Stifel and communicated the BBI counterproposal. A series of discussions and negotiations involving Mr. Kirby and other representatives of BBI, including the BBI KBW team, and Mr. Reichert and other representatives of Stifel ensued in which the parties discussed BBI’s preference for a fixed, higher exchange ratio and Stifel’s preference for a period of exclusivity for Stifel to continue its due diligence investigation and negotiate a possible acquisition of BBI. In addition, as authorized by the BBI board at its April 4, 2018, meeting, the BBI KBW team attempted to contact Company A on April 5, 2018, to give Company A an opportunity to improve its proposal. On April 6, 2018, prior to a meeting of the BBI board, the BBI KBW team spoke with Company A and informed Company A that its proposal was lower than that of another bidder that BBI believed was, overall, a stronger cultural and strategic fit. Company A was informed that, unless it intended to improve its proposal, BBI believed it would reach acceptable terms with the other bidder. During that conversation, Company A orally revised its proposal to increase the low end of its proposed price range but did not increase the high end of its range. On April 6, 2018, Stifel submitted a revised proposal to BBI with a fixed exchange ratio.

On April 6, 2018, the BBI board held a special meeting, with the BBI KBW team and representatives of Lewis Rice in attendance, to review Stifel’s revised proposal and to receive an update from the BBI KBW team regarding the latest discussions with Company A, including the revised price range of Company A’s proposal. The BBI board noted that the revised proposal from Stifel reflected the financial terms sought by the BBI board

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and discussions between Stifel and BBI following the April 4, 2018, BBI board meeting. Stifel’s revised proposal provided for a fixed exchange ratio of shares of Stifel common stock for shares of BBI common stock. Stifel also requested a 30-day exclusivity period to complete its due diligence and reach a definitive agreement with BBI. The BBI board further considered Stifel’s historical financial performance, the liquidity and average trading volume of Stifel common stock, Stifel’s capitalization, history of dividends and other public information about Stifel. The BBI board also noted that Stifel’s business plan was to provide additional capital and funding of BBI Bank to allow it to expand and grow its operations, keeping most of the senior management of BBI Bank. The revised proposal also included, among other things, a requirement that certain key management personnel agree to continue employment with BBI Bank for an agreed term. By resolutions adopted on April 6, 2018, the BBI board accepted the terms of the revised indication of interest from Stifel. Later that day, Mr. Kirby and the BBI KBW team communicated the BBI board’s acceptance to Stifel.

Mr. Reichert submitted a due diligence request list to Mr. Kirby and other members of BBI management on April 9, 2018. Beginning in mid-April 2018, BBI commenced uploading additional materials to the online data room in response to Stifel’s request. On April 10, 2018, an expanded team from Stifel began an on-site due diligence review of BBI and its subsidiaries, including BBI Bank; off-site due diligence, primarily through the online data room, was undertaken by other local Stifel personnel and by Stifel’s outside counsel at Arnold & Porter Kaye Scholer LLP (which we sometimes refer to as “Arnold & Porter”).

On April 11, 2018, the BBI board engaged FIG Partners to act as financial advisor to the BBI board in connection with BBI’s consideration of a possible business combination. The engagement contemplated that FIG Partners would provide an independent analysis of the proposed transaction and an opinion to the BBI board as to the fairness, from a financial point of view, to the BBI shareholders of the consideration to be received in a potential business combination transaction.

Beginning on April 17, 2018, Mr. Kirby and Mr. Reichert discussed possible terms for agreements between Stifel and key BBI Bank management employees regarding the continued employment by BBI Bank of those employees after the merger. Over the next several days, Mr. Reichert interviewed Stanley Cornish, David Gamache, Brian Leeker and other members of BBI Bank senior management. On April 26, 2018, Stifel provided to BBI proposed continuation agreements for these BBI Bank management employees. Discussions with respect to the proposed terms and conditions of these agreements were conducted between Mr. Kirby and Mr. Reichert and continued into early May 2018.

On April 18, 2018, Arnold & Porter circulated to Lewis Rice and BBI a draft of the merger agreement. Stifel conditioned the signing of a final merger agreement upon several related matters, including a unanimous vote of the BBI board, the execution by each of BBI’s directors and executive officers and Castle Creek, each in the capacity of a BBI shareholder, of a voting agreement requiring that such person to vote his or her shares of BBI voting common stock for the approval of the merger proposal at any meeting of the BBI shareholders held to consider and vote on the merger and the signing of continuation agreements by 21 officers and key business relationship employees of BBI Bank, including all of BBI Bank’s executive officers. Negotiation of the merger agreement and the related transaction documents, and discussions regarding the merger agreement among BBI and its legal and financial advisors, continued throughout late April and the first part of May 2018.

During a call on April 25, 2018, Mr. Reichert and other representatives of Stifel and the Stifel KBW team communicated to Mr. Kirby and the BBI KBW team Stifel’s proposal to adjust the agreed fixed exchange ratio downward to reflect Stifel’s preliminary diligence conclusions as to the projected earnings of BBI. The BBI board held a special meeting on April 27, 2018, to consider Stifel’s proposed change to the exchange ratio. At the time of that BBI board meeting, the price per share of BBI common stock implied by Stifel’s proposed adjusted exchange ratio was still greater than the high end of Company A’s proposal from early April 2018. The BBI board decided to defer taking any action on Stifel’s proposed pricing adjustment until all other terms of the merger could be reviewed as part of the overall merger agreement. On April 27, 2018, Arnold & Porter provided to Lewis Rice a proposed draft of the voting agreement for BBI’s directors and executive officers and certain

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other BBI shareholders and a revised draft of the merger agreement. On April 28, 2018, Mr. Reichert and Mr. Kirby discussed the terms of the revised merger agreement and BBI’s expectation that, in the context of the proposed adjustment, the merger agreement would be drafted to be fair to both sides. On May 1, 2018, Lewis Rice delivered to Arnold & Porter a revised draft of the merger agreement that reflected a few open, substantive business issues.

The BBI board held a special meeting on May 4, 2018. Present at the meeting were members of the BBI KBW team and attorneys from Lewis Rice. A representative of FIG Partners participated via telephone. At the meeting, the FIG Partners representative discussed the transaction proposed by Stifel, focusing on its financial terms, and informally advised the board as to the fairness, from a financial point of view, of the proposed Stifel transaction to the BBI shareholders. Representatives from Lewis Rice participated in the meeting and discussed with the BBI board the terms and conditions of the merger agreement. The consensus of the BBI board, particularly in light of Stifel’s strong financial condition and prospects, the fact that the decreased exchange ratio proposed by Stifel on April 25, 2018, still represented a higher price per share of BBI common stock than the price contemplated by Company A’s proposal and the view that finalization of a definitive merger agreement with Stifel appeared likely, was to accept the decreased exchange ratio proposed by Stifel on April 25, 2018.

Beginning in early May 2018, BBI conducted a reverse due diligence investigation of Stifel. On May 7, 2018, the BBI board was provided with a package of documents containing financial and other public information about Stifel. On that same day, BBI management conducted a conference call with Stifel representatives, including senior executives of Stifel, to discuss business, financial, operational, legal and other due diligence matters concerning Stifel. A representative of the BBI KBW team participated on the conference call to assist with facilitating the discussions between BBI management and the Stifel representatives. Members of the Stifel KBW team also joined the conference call.

On May 9, 2018, the BBI board held a special meeting. Representatives from Lewis Rice participated in the meeting. At this meeting, FIG Partners delivered to the BBI board its oral opinion, which was subsequently confirmed in writing on May 10, 2018, to the effect that, as of such date, the exchange ratio was fair to the BBI shareholders from a financial point of view. For a description of FIG Partners’ opinion, please refer to “—Opinion of FIG Partners, LLC” below. At the meeting, the BBI board reviewed in detail the final merger agreement, ancillary agreements, including the voting agreements and continuation agreements, and related summaries and supplemental materials, together with the final fairness opinion of FIG Partners. At the meeting, the BBI board unanimously approved the merger agreement and ancillary agreements, subject to the required approval of the BBI shareholders and applicable regulatory authorities. After the meeting, the members of the BBI board and BBI’s executive officers signed their respective voting agreements. Additionally, the requisite 21 officers and key business relationship employees of BBI Bank signed continuation agreements.

On May 10, 2018, BBI and Stifel executed the merger agreement. Shortly thereafter, Stifel issued a press release publicly announcing the transaction.

BBI’s Reasons for the Merger and Recommendation of the BBI Board

At a special meeting held on May 9, 2018, the BBI board unanimously approved the merger agreement, the related plan of merger and the merger, determined that the merger agreement, the related plan of merger and the merger are in the best interests of BBI and its shareholders and declared the merger to be advisable.

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In reaching its decision to approve the merger agreement, the plan of merger and the merger and to unanimously recommend that holders of BBI voting common stock approve the merger proposal and the adjournment proposal, the BBI board evaluated the merger in consultation with BBI management, as well as BBI’s financial and legal advisors, and considered a number of factors, including the following material factors:

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The BBI board also considered a number of uncertainties and risks in its deliberations concerning the transactions contemplated by the merger agreement, including the following: