Company: OSBC
Filing Date: 2025-05-08
Form Type: 424B3
Source: 0001104659-25-046065
Chunk: 148

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-08
Form: 424B3
Chunk 148
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 lending activities include making commercial and consumer loans, primarily on a secured basis. Commercial lending focuses on business, equipment, capital, construction, inventory, health care and real estate lending, as well as lease financing. Installment lending includes direct loans to consumers and commercial customers.

We also offer a full complement of electronic banking services such as online and mobile banking and corporate cash management products including remote deposit capture, mobile deposit capture, investment sweep accounts, zero balance accounts, automated tax payments, ATM access, telephone banking, lockbox accounts, automated clearing house transactions, account reconciliation, controlled disbursement, detail and general information reporting, foreign and domestic wire transfers, vault services for currency and coin, and checking accounts. Additionally, we provide a wide range of wealth management, investment, agency, and custodial services for individual, corporate, and not-for-profit clients. These services include the administration of estates and personal trusts, as well as the management of investment accounts for individuals, employee benefit plans, and charitable foundations. We also originate residential mortgages, offering a wide range of mortgage products including conventional, government, and jumbo loans. We also handle secondary marketing of those mortgages.

Old Second is headquartered at 37 South River Street, Aurora, Illinois 60507. More information about Old Second is available by visiting the “Investor Relations” tab of its website at www.oldsecond.com. Information contained on Old Second’s website does not constitute part of, and is not incorporated into, this proxy statement/prospectus. For a complete description of Old Second’s business, financial condition, results of operations and other important information, please refer to Old Second’s filings with the SEC that are incorporated by reference in this document, including its Annual Report on Form 10-K for the year ended December 31, 2024. For instructions on how to find copies of these documents, see “Where You Can Find More Information” in the forepart of this proxy statement/prospectus.

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#### INFORMATION ABOUT BANCORP FINANCIAL, INC.
In this section, references to the “Company” or “Bancorp Financial” refer to Bancorp Financial, Inc. and references to “we,” “us,” and “our” mean the combined business of Bancorp Financial, Evergreen Bank Group and its wholly-owned subsidiaries.

Bancorp Financial, Inc., a Delaware corporation, was founded in 2006 and is headquartered in Oak Brook, Illinois. Bancorp Financial operates as the bank