# EDGAR Filing Document

**Accession Number:** 0000887343
**File Stem:** 0000887343-25-000242
**Filing Date:** 2025-9
**Character Count:** 44352
**Document Hash:** 2497f78571ba2863ed450b0c4306a23e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000887343-25-000242.hdr.sgml**: 20250903

**ACCESSION NUMBER**: 0000887343-25-000242

**CONFORMED SUBMISSION TYPE**: 8-K/A

**PUBLIC DOCUMENT COUNT**: 14

**CONFORMED PERIOD OF REPORT**: 20250902

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20250903

**DATE AS OF CHANGE**: 20250903

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** COLUMBIA BANKING SYSTEM, INC.
- **CENTRAL INDEX KEY:** 0000887343
- **STANDARD INDUSTRIAL CLASSIFICATION:** STATE COMMERCIAL BANKS [6022]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 911422237
- **STATE OF INCORPORATION:** WA
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-20288
- **FILM NUMBER:** 251287799

**BUSINESS ADDRESS:**
- **STREET 1:** 1301 A STREET
- **CITY:** TACOMA
- **STATE:** WA
- **ZIP:** 98402
- **BUSINESS PHONE:** 2533051900

**MAIL ADDRESS:**
- **STREET 1:** 1301 A STREET
- **CITY:** TACOMA
- **STATE:** WA
- **ZIP:** 98402

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** COLUMBIA BANKING SYSTEM INC
- **DATE OF NAME CHANGE:** 19930328

?xml version='1.0' encoding='ASCII'? colb-20250902

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM 8-K/A**

**CURRENT REPORT**

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report: **September 2, 2025**

(Date of earliest event reported)

**Columbia Banking System, Inc.**

(Exact Name of Registrant as Specified in Its Charter)

---

| | | |
|:---|:---|:---|
| **<u>Washington</u>** | **<u>000-20288</u>** | **<u>91-1422237</u>** |
| (State or Other Jurisdiction of Incorporation or Organization) | (Commission File Number) | (I.R.S. Employer Identification Number) |

---

**1301 A Street**

**Tacoma, Washington 98402-4200**

(address of Principal Executive Offices)(Zip Code)

**(253) 305-1900**

(Registrant's Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[ ☐ ]&nbsp;&nbsp;&nbsp;&nbsp;Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

[ ☐ ]&nbsp;&nbsp;&nbsp;&nbsp;Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

[ ☐ ]&nbsp;&nbsp;&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

[ ☐ ]&nbsp;&nbsp;&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| <u>TITLE OF EACH CLASS</u> | <u>TRADING SYMBOL</u> | <u>NAME OF EXCHANGE</u> |
| **Common Stock** | **COLB** | **The NASDAQ Stock Market LLC** |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company [ ☐]

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 accounting standards provided pursuant to Section 13(a) of the Exchange Act [ ]

------

**Explanatory Note** 

On September 2, 2025, Columbia Banking System, Inc., a Washington corporation ("Columbia"), filed a Current Report on Form 8-K (the "Original Report") to report that, effective as of August 31, 2025, Columbia completed its acquisition of Pacific Premier Bancorp, Inc., a Delaware corporation ("Pacific Premier"), pursuant to the Agreement and Plan of Merger, dated April 23, 2025 (the "Merger Agreement"), by and among Columbia, Pacific Premier, and Balboa Merger Sub, Inc., a Delaware corporation and a direct, wholly owned subsidiary of Columbia ("Merger Sub"). Pursuant to the Merger Agreement, (i) Merger Sub merged with and into Pacific Premier (the "Merger"), with Pacific Premier as the surviving corporation, and (ii) immediately thereafter, Pacific Premier merged with and into Columbia, with Columbia as the surviving entity (the "Second Step Merger" and, together with the Merger, the "Mergers"). Promptly following the closing of the Second Step Merger, Pacific Premier Bank, National Association, a national banking association and a wholly owned subsidiary of Pacific Premier, merged with and into Columbia Bank, an Oregon state-chartered commercial bank and a wholly owned subsidiary of Columbia (the "Bank Merger"), with Columbia Bank surviving the Bank Merger.

This amendment to the Original Report (the "Amendment") is being filed to provide the financial statements and pro forma financial information required by Item 9.01 of Form 8-K.

The pro forma financial information included in this Amendment has been presented for informational purposes only, as required by Form 8-K. It does not purport to represent the actual results of operations that Columbia and Pacific Premier would have achieved had the companies been combined during the periods presented in the pro forma financial information and is not intended to project the future results of operations that the combined company may achieve after completion of the Mergers. Except as described in this Amendment, all other information in the Original Report remains unchanged.

**Item 9.01.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Financial Statements and Exhibits.** 

(a) Financial statements of businesses or funds acquired.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The financial statements of Pacific Premier required by Item 9.01(a) of Form 8-K are attached hereto as Exhibit 99.1 and incorporated by reference into this Item 9.01(a).

(b) Pro forma financial information.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The pro forma financial information required by Item 9.01(b) of Form 8-K is attached hereto as Exhibit 99.2 and incorporated herein by reference into this Item 9.01(b).

(d) Exhibits.

The following exhibits are filed as part of this Current Report:

---

| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 23.1 | <u>[Consent of Deloitte & Touche LLP, Independent Registered Public Accounting Firm for Pacific Premier Bancorp, Inc.](ex231consentofindependentr.htm)</u> |
| 99.1 | <u>[Audited consolidated balance sheets of Pacific Premier Bancorp, Inc. as of December 31, 2024 and December 31, 2023, the related consolidated statements of operations, comprehensive income, changes in stockholders' equity and cash flows of Pacific Premier Bancorp, Inc. for each of the three years in the period ended December 31, 2024, and the notes related thereto (incorporated by reference to Part II, Item 8 of Pacific Premier Bancorp, Inc.'s Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on February 28, 2025 (File No. 000-22193)).](https://www.sec.gov/ix?doc=/Archives/edgar/data/1028918/000102891825000014/ppbi-20241231.htm)</u> |
| 99.2 | <u>[Unaudited pro forma condensed combined balance sheet as of June 30, 2025, the unaudited pro forma condensed combined statement of income for the fiscal year ended December 31, 2024 and June 30, 2025, and the notes related thereto.](proforma20250630.htm)</u> |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document) |

---

------

**<u>SIGNATURES</u>**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | |
|:---|:---|
| | Columbia Banking System, Inc.<br>(Registrant) |
| Dated: September 3, 2025 | By:<u>/s/ Kumi Yamamoto Baruffi</u><br>&nbsp;&nbsp;&nbsp;&nbsp; Kumi Yamamoto Baruffi<br>&nbsp;&nbsp;&nbsp;&nbsp; EVP, General Counsel and Corporate Secretary |

---

## Exhibit 23.1

**Exhibit 23.1**

**Consent Of Independent Registered Public Accounting Firm** 

We consent to the incorporation by reference in Registration Statement Nos. 333-273424, 333-279235, 333-297237, 333-297238, 333-160371, 333-225955 and 333-270191 on Form S-8 and Registration Statement No. 333-283985 on Form S-3 of Columbia Banking System, Inc. of our reports dated February 28, 2025 relating to the financial statements of Pacific Premier Bancorp, Inc. and the effectiveness of Pacific Premier Bancorp, Inc.'s internal control over financial reporting, incorporated by reference in this Current Report on Form 8-K/A dated September 3, 2025.

/s/ Deloitte & Touche LLP

Costa Mesa, CA

September 3, 2025

## Exhibit 99.2

**UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION**

The following unaudited pro forma condensed combined financial information and the accompanying notes (the "pro forma financial information") are presented to illustrate the effects of the accounting for the mergers.

The accompanying unaudited pro forma condensed combined balance sheet as of June 30, 2025 combines the historical consolidated balance sheets of Columbia Banking System, Inc. ("Columbia") and Pacific Premier Bancorp, Inc. (Pacific Premier") as of such date and reflects adjustments that depict the accounting for the mergers required by GAAP (the "pro forma balance sheet transaction accounting adjustments"). Also, the unaudited pro forma condensed combined statements of income for the six months ended June 30, 2025 and for the year ended December 31, 2024 combine the historical consolidated statements of income of Columbia and Pacific Premier for the same periods and reflects adjustments that depict the effects of the pro forma balance sheet transaction accounting adjustments assuming those adjustments were made on January 1, 2024 (the "pro forma income statement transaction accounting adjustments"). We refer to pro forma balance sheet transaction accounting adjustments and pro forma statements of income transaction accounting adjustments collectively as the "transaction accounting adjustments."

The unaudited pro forma financial information is based on and should be read in conjunction with the separate historical financial statements and notes thereto included in each of Columbia's and Pacific Premier's SEC filings incorporated by reference into this joint proxy statement/prospectus, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the historical audited consolidated financial statements of Columbia and accompanying notes included in Columbia's Annual Report on Form 10-K for the year ended December 31, 2024;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the historical unaudited condensed consolidated financial statements of Columbia and accompanying notes included in Columbia's Quarterly Report on Form 10-Q for the quarter ended June 30, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the historical audited consolidated financial statements of Pacific Premier and accompanying notes included in Pacific Premier's Annual Report on Form 10-K for the year ended December 31, 2024; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the historical unaudited consolidated financial statements of Pacific Premier and accompanying notes included in Pacific Premier's Quarterly Report on Form 10-Q for the quarter ended June 30, 2025.

The unaudited pro forma financial information is provided for illustrative information purposes only. The unaudited pro forma financial information is not necessarily, and should not be assumed to be, an indication of the actual results that would have been achieved had the acquisition been completed as of the dates indicated or that may be achieved in the future.

------

**UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET**

The unaudited pro forma condensed combined balance sheet as of June 30, 2025, reflects adjustments that depict the accounting for the mergers required by GAAP.

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| | **June 30, 2025** | **June 30, 2025** | **June 30, 2025** | **June 30, 2025** | **June 30, 2025** |
| (dollars in thousands) | **Columbia Historical** | **Pacific Premier Historical** | **Pro Forma Adjustments** | **Notes** | **Pro Forma Combined** |
| **ASSETS** |  |  |  |  |  |
| Cash and due from banks  | $608057 | $166647 | $— |  | $774704 |
| Interest bearing cash and temporary investments  | 1334113 | 625743 | (185000) | **A** | 1774856 |
| &nbsp;&nbsp;&nbsp;&nbsp;Total cash and cash equivalents | 1942170 | 792390 | (185000) |  | 2549560 |
| Investment securities |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Equity and other, at fair value | 92958 |  |  |  | 92958 |
| &nbsp;&nbsp;&nbsp;Available for sale, at fair value | 8653172 | 1581731 |  |  | 10234903 |
| &nbsp;&nbsp;&nbsp;Held to maturity, at amortized cost | 2013 | 1687871 | (310000) | **B** | 1379884 |
| Loans held for sale, at fair value | 65590 | 751 |  |  | 66341 |
| Loans and leases | 37637013 | 11902079 | (472000) | **C** | 49067092 |
| Allowance for credit losses on loans and leases | (420907) | (170663) | 74663 | **D** | (516907) |
| &nbsp;&nbsp;&nbsp;&nbsp;Net loans and leases | 37216106 | 11731416 | (397337) |  | 48550185 |
| Restricted equity securities | 161380 | 97717 |  |  | 259097 |
| Premises and equipment, net | 356879 | 45666 | 12000 | **E** | 414545 |
| Goodwill | 1029234 | 901312 | (399133) | **F** | 1531413 |
| Other intangible assets, net | 430443 | 27127 | 386632 | **G** | 844202 |
| Bank-owned life insurance | 704919 | 490770 |  |  | 1195689 |
| Deferred tax asset, net | 299043 | 93450 | 122617 | **H** | 515110 |
| Other assets | 947535 | 332971 |  |  | 1280506 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total assets | $51901442 | $17783172 | $(770221) |  | $68914393 |
| **LIABILITIES AND SHAREHOLDERS' EQUITY** |  |  |  |  |  |
| Deposits |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Non-interest bearing | $13219631 | $4687795 | $— |  | $17907426 |
| &nbsp;&nbsp;&nbsp;Interest bearing | 28523026 | 9809578 | 7000 | **I** | 38339604 |
| &nbsp;&nbsp;&nbsp;&nbsp;Total deposits | 41742657 | 14497373 | 7000 |  | 56247030 |
| Securities sold under agreements to repurchase | 191435 |  |  |  | 191435 |
| Borrowings | 3350000 |  |  |  | 3350000 |
| Junior subordinated debentures, at fair value | 323015 |  |  |  | 323015 |
| Junior and other subordinated debentures, at amortized cost | 107554 | 124023 | (1000) | **J** | 230577 |
| Other liabilities | 844899 | 186358 |  |  | 1031257 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total liabilities | 46559560 | 14807754 | 6000 |  | 61373314 |
| **SHAREHOLDERS' EQUITY** |  |  |  |  |  |
| Common stock | 5826488 | 2401498 | 8126 | **K** | 8236112 |
| (Accumulated deficit) retained earnings | (150822) | 639189 | (820249) | **L** | (331882) |
| Accumulated other comprehensive (loss) income | (333784) | (65269) | 65269 | **M** | (333784) |
| &nbsp;&nbsp;&nbsp;&nbsp;Total shareholders' equity | 5341882 | 2975418 | (746854) |  | 7570446 |
| &nbsp;&nbsp;&nbsp;&nbsp;Total liabilities and shareholders' equity | $51901442 | $17783172 | $(740854) |  | $68943760 |

---

See accompanying notes to the unaudited pro forma condensed combined financial information.

------

**UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME** 

The unaudited pro forma condensed combined statement of income for the six months ended June 30, 2025, reflects adjustments that depict the effects of the pro forma balance transaction accounting adjustments assuming those adjustments were made on January 1, 2024.

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** | **Six Months Ended June 30, 2025** |
| (in thousands) | **Columbia Historical** | **Pacific Premier Historical** | **Reclassification<br>Adjustments (Note 3)** | **Notes** | **Pacific Premier As Adjusted** | **Pro Forma Adjustments** | **Notes** | **Pro Forma Combined** |
| **INTEREST INCOME** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Interest and fees on loans and leases | $1116905 | $298949 | $— |  | $298949 | $83028 | **N** | $1498882 |
| &nbsp;&nbsp;&nbsp;Interest and dividends on investment securities | 168816 | 77567 | (15929) | **1** | 61638 | 23961 | **O** | 254415 |
| &nbsp;&nbsp;&nbsp;Interest on temporary investments and interest bearing deposits | 32211 |  | 15929 | **1** | 15929 |  |  | 48140 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total interest income | 1317932 | 376516 |  |  | 376516 | 106989 |  | 1801437 |
| **INTEREST EXPENSE** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Interest on deposits | 356788 | 117949 |  |  | 117949 |  |  | 474737 |
| &nbsp;&nbsp;&nbsp;Interest on securities sold under agreement to repurchase and federal funds purchased | 1929 |  |  |  |  |  |  | 1929 |
| &nbsp;&nbsp;&nbsp;Interest on borrowings | 70616 | 4 |  |  | 4 |  |  | 70620 |
| &nbsp;&nbsp;&nbsp;Interest on junior and other subordinated debentures | 17158 | 8441 |  |  | 8441 | 125 | **Q** | 25724 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total interest expense | 446491 | 126394 |  |  | 126394 | 125 |  | 573010 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net interest income | 871441 | 250122 |  |  | 250122 | 106864 |  | 1228427 |
| **PROVISION (RECAPTURE) FOR CREDIT LOSSES** | 56852 | (5796) |  |  | (5796) |  |  | 51056 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net interest income after provision (recapture) for credit losses | 814589 | 255918 |  |  | 255918 | 106864 |  | 1177371 |
| **NON-INTEREST INCOME** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Service charges on deposits | 38970 | 5207 |  |  | 5207 |  |  | 44177 |
| &nbsp;&nbsp;&nbsp;Card-based fees | 27130 | 1769 |  |  | 1769 |  |  | 28899 |
| &nbsp;&nbsp;&nbsp;Financial services and trust revenue | 11029 | 19122 |  |  | 19122 |  |  | 30151 |
| &nbsp;&nbsp;&nbsp;Residential mortgage banking revenue, net | 16677 |  |  |  |  |  |  | 16677 |
| &nbsp;&nbsp;&nbsp;Other income | 37033 | 12932 |  |  | 12932 |  |  | 49965 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total non-interest income | 130839 | 39030 |  |  | 39030 |  |  | 169869 |
| **NON-INTEREST EXPENSE** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Salaries and employee benefits | 300122 | 106080 | 2357 | **2** | 108437 |  |  | 408559 |
| &nbsp;&nbsp;&nbsp;Occupancy and equipment, net | 95348 | 18187 | 15521 | **2** | 33708 |  |  | 129056 |
| &nbsp;&nbsp;&nbsp;Intangible amortization | 53805 | 5067 |  |  | 5067 | 28786 | **S** | 87658 |
| &nbsp;&nbsp;&nbsp;Legal settlement | 55000 |  |  |  |  |  |  | 55000 |
| &nbsp;&nbsp;&nbsp;Other expenses | 113842 | 75334 | (17878) | **2** | 57456 |  |  | 171298 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total non-interest expense | 618117 | 204668 |  |  | 204668 | 28786 |  | 851571 |
| &nbsp;&nbsp;&nbsp;Income before provision for income taxes | 327311 | 90280 |  |  | 90280 | 78078 |  | 495669 |
| &nbsp;&nbsp;&nbsp;Provision for income taxes | 88279 | 22198 |  |  | 22198 | 20691 | **U** | 131168 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net income | $239032 | $68082 | $— |  | $68082 | $57387 |  | $364501 |
| **Earnings per common share:** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Basic | $1.14 | $0.70 |  |  |  |  |  | $1.22 |
| &nbsp;&nbsp;&nbsp;Diluted | $1.14 | $0.70 |  |  |  |  |  | $1.22 |
| **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Basic | 208964 | 94932 |  |  |  | (6016) | **V** | 297880 |
| &nbsp;&nbsp;&nbsp;Diluted | 209965 | 94968 |  |  |  | (6052) | **W** | 298881 |

---

See accompanying notes to the unaudited pro forma condensed combined financial information.

------

**UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME** 

The unaudited pro forma condensed combined statement of income for the fiscal year ended December 31, 2024, reflects adjustments that depict the effects of the pro forma balance transaction accounting adjustments assuming those adjustments were made on January 1, 2024.

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** | **Year Ended December 31, 2024** |
| (in thousands) | **Columbia Historical** | **Pacific Premier Historical** | **Reclassification<br>Adjustments (Note 3)** | **Notes** | **Pacific Premier As Adjusted** | **Pro Forma Adjustments** | **Notes** | **Pro Forma Combined** |
| **INTEREST INCOME** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Interest and fees on loans and leases | $2320364 | $655206 | $— |  | $655206 | $208155 | **N** | $3183725 |
| &nbsp;&nbsp;&nbsp;Interest and dividends on investment securities | 344649 | 167362 | (52650) | **1** | 114712 | 50467 | **O** | 509828 |
| &nbsp;&nbsp;&nbsp;Interest on temporary investments and interest bearing deposits | 90227 |  | 52650 | **1** | 52650 |  |  | 142877 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total interest income | 2755240 | 822568 |  |  | 822568 | 258622 |  | 3836430 |
| **INTEREST EXPENSE** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Interest on deposits | 802806 | 257988 |  |  | 257988 | (7000) | **P** | 1053794 |
| &nbsp;&nbsp;&nbsp;Interest on securities sold under agreement to repurchase and federal funds purchased | 4873 |  |  |  |  |  |  | 4873 |
| &nbsp;&nbsp;&nbsp;Interest on borrowings | 190241 | 8083 |  |  | 8083 |  |  | 198324 |
| &nbsp;&nbsp;&nbsp;Interest on junior and other subordinated debentures | 38918 | 19546 |  |  | 19546 | 250 | **Q** | 58714 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total interest expense | 1036838 | 285617 |  |  | 285617 | (6750) |  | 1315705 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net interest income | 1718402 | 536951 |  |  | 536951 | 265372 |  | 2520725 |
| **PROVISION FOR CREDIT LOSSES** | 105924 | 4789 |  |  | 4789 | 48000 | **R** | 158713 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net interest income after provision for credit losses | 1612478 | 532162 |  |  | 532162 | 217372 |  | 2362012 |
| **NON-INTEREST INCOME** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Service charges on deposits | 71517 | 10875 |  |  | 10875 |  |  | 82392 |
| &nbsp;&nbsp;&nbsp;Card-based fees | 57089 | 3452 |  |  | 3452 |  |  | 60541 |
| &nbsp;&nbsp;&nbsp;Financial services and trust revenue | 20208 | 37119 |  |  | 37119 |  |  | 57327 |
| &nbsp;&nbsp;&nbsp;Residential mortgage banking revenue, net | 24108 |  |  |  |  |  |  | 24108 |
| &nbsp;&nbsp;&nbsp;Other income | 38044 | 31392 |  |  | 31392 |  |  | 69436 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total non-interest income | 210966 | 82838 |  |  | 82838 |  |  | 293804 |
| **NON-INTEREST EXPENSE** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Salaries and employee benefits | 588830 | 211057 | 4960 | **2** | 216017 |  |  | 804847 |
| &nbsp;&nbsp;&nbsp;Occupancy and equipment, net | 182372 | 42380 | 29669 | **2** | 72049 |  |  | 254421 |
| &nbsp;&nbsp;&nbsp;Intangible amortization | 119431 | 11091 |  |  | 11091 | 64138 | **S** | 194660 |
| &nbsp;&nbsp;&nbsp;Other expenses | 214061 | 138003 | (34629) | **2** | 103374 | 185000 | **T** | 502435 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total non-interest expense | 1104694 | 402531 |  |  | 402531 | 249138 |  | 1756363 |
| &nbsp;&nbsp;&nbsp;Income before provision for income taxes | 718750 | 212469 |  |  | 212469 | (31766) |  | 899453 |
| &nbsp;&nbsp;&nbsp;Provision for income taxes | 185075 | 53667 |  |  | 53667 | (8418) | **U** | 230324 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net income | $533675 | $158802 | $— |  | $158802 | $(23348) |  | $669129 |
| **Earnings per common share:** |  |  |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Basic | $2.56 | $1.65 |  |  |  |  |  | $2.25 |
| &nbsp;&nbsp;&nbsp;Diluted | $2.55 | $1.65 |  |  |  |  |  | $2.24 |
| **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** | **Weighted average number of common shares outstanding:** |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Basic | 208463 | 94579 |  |  |  | (5663) | **V** | 297379 |
| &nbsp;&nbsp;&nbsp;Diluted | 209337 | 94683 |  |  |  | (5767) | **W** | 298253 |

---

See accompanying notes to the unaudited pro forma condensed combined financial information.

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**NOTES TO THE UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION**

**Note 1—Basis of Presentation**

The unaudited pro forma financial information and explanatory notes have been prepared in accordance with Article 11 of Regulation S-X to illustrate the effects of the mergers under the acquisition method of accounting in Accounting Codification Standards 805, Business Combinations (ASC 805) with Columbia treated as the accounting acquirer. Under the acquisition method of accounting, the assets and liabilities of Pacific Premier (as the accounting acquiree) will be recorded mostly at their respective fair values, as of the effective date of the mergers, and the excess of the fair value of Pacific Premier's net assets over the consideration transferred will be recorded as goodwill. In addition, merger-related costs incurred by Columbia, the accounting acquirer, are accounted for as expenses in the periods in which the costs are incurred and the services received.

As discussed in Note 3, certain reclassifications were made to align Pacific Premier's historical financial statement presentation with that of Columbia. The accounting policies of both Columbia and Pacific Premier are currently under review, and Columbia and Pacific Premier have not identified all adjustments necessary to conform the respective accounting policies into a single accounting policy. As a result of that review, differences could be identified between the accounting policies of the two companies that, when aligned, could have a material impact on the Columbia's financial information.

The transaction accounting adjustments are preliminary and are subject to change as additional information becomes available and as additional analysis is performed. The preliminary transaction accounting adjustments have been made solely for the purpose of providing the unaudited pro forma financial information. The transaction accounting adjustments are based upon available information and certain assumptions considered reasonable, and may be revised as additional information becomes available.

**Note 2—Preliminary Consideration Transferred and Allocation of Consideration Transferred**

The transaction accounting adjustments depict the accounting for the mergers, including the determination of the fair value of preliminary consideration transferred and allocation of the preliminary consideration transferred to assets acquired and liabilities assumed. The excess of the consideration transferred over the fair value of assets acquired and liabilities assumed is reflected as goodwill.

Refer to the table below for the preliminary calculation of estimated merger consideration transferred:

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| | |
|:---|:---|
| (dollars and shares in thousands) |  |
| **Share consideration:** | **Amount** |
| Shares of Pacific Premier common stock outstanding as of August 29, 2025 | 97126 |
| Shares of Pacific Premier restricted stock units and dividend equivalents outstanding as of August 29, 2025 | 49 |
| Total Pacific Premier shares outstanding plus restricted stock units | 97175 |
| Exchange ratio | 0.9150 |
| Number of shares of Columbia common stock to be issued to Pacific Premier shareholders | 88915 |
| Columbia's market price per common share as of August 29, 2025 | $26.77 |
| &nbsp;&nbsp;&nbsp;Preliminary fair value of estimated merger consideration transferred | $2380257 |

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The final consideration transferred is based upon the completion of the mergers were determined based on the closing price of Columbia common stock on the closing date and the number of issued and outstanding shares of Pacific Premier common stock immediately prior to the effective time. Final consideration transferred may differ from the amounts reflected in the unaudited pro forma financial information, and the differences may be material.

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Columbia estimated the fair value of certain Pacific Premier assets and liabilities based on a preliminary valuation analysis, due diligence information, information presented in Pacific Premier's SEC filings and other publicly available information. As of the date of this Current Report on Form 8-K, Columbia has not completed the valuation analysis and calculations in sufficient detail necessary to arrive at the required estimates of the fair value of Pacific Premier's assets acquired or liabilities assumed for accounting purposes, other than a preliminary estimate for intangible assets and certain financial assets and financial liabilities. Accordingly, apart from the aforementioned, certain Pacific Premier assets and liabilities are presented at their respective carrying amounts and should be treated as preliminary fair values. A final determination of the fair value of Pacific Premier's assets and liabilities will be based on Pacific Premier's actual assets and liabilities as of the effective time. Actual adjustments may differ from the amounts reflected in the unaudited pro forma financial information, and the differences may be material.

A final determination of the fair value of Pacific Premier's assets acquired and liabilities assumed will be performed. Any changes in the fair values of the net assets or total purchase price as compared with the information shown in the unaudited pro forma financial information may change the amount of the total purchase price allocated to goodwill and other assets and liabilities and may impact the combined company's statement of income. The final purchase price allocation may be materially different than the preliminary purchase price allocation presented in the unaudited pro forma financial information.

The following table sets forth a preliminary allocation of the estimated merger consideration transferred to the fair value of the identified tangible and intangible assets and liabilities assumed of Pacific Premier using Pacific Premier's unaudited consolidated balance sheet as of June 30, 2025:

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| | | |
|:---|:---|:---|
| (in thousands) | June 30, 2025 | June 30, 2025 |
| Fair value consideration paid to Pacific Premier shareholders |  |  |
| Cash paid |  | $— |
| Fair value of common shares issued and exchanged |  | 2380257 |
| &nbsp;&nbsp;Preliminary fair value of estimated merger consideration transferred |  | $2380257 |
| Fair value of assets acquired: |  |  |
| Cash and due from banks | $792390 |  |
| Available for sale | 1581731 |  |
| Held to maturity | 1377871 |  |
| Loans and leases | 11382079 |  |
| Restricted equity securities | 97717 |  |
| Premises and equipment | 57666 |  |
| Other intangible assets | 413759 |  |
| Bank-owned life insurance | 490770 |  |
| Deferred tax asset, net | 164127 |  |
| Other assets | 332971 |  |
| &nbsp;&nbsp;Total assets acquired | $16691832 |  |
| Fair value of liabilities assumed: |  |  |
| Deposits | $14504373 |  |
| Junior and other subordinated debentures | 123023 |  |
| Other liabilities | 186358 |  |
| &nbsp;&nbsp;Total liabilities assumed | $14813754 |  |
| Net assets acquired |  | $1878078 |
| Preliminary pro forma goodwill |  | $502179 |

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**Note 3—Effect of Reclassification Adjustments**

During the preparation of the unaudited pro forma financial information, Columbia performed certain procedures to identify transaction accounting adjustments to be made as a result of material differences in the financial statement presentation of Columbia and Pacific Premier. Certain reclassification adjustments have been made to conform Pacific Premier's historical financial statement presentation to Columbia's historical financial statement presentation. Reclassifications have also been made to condense historical Columbia's amounts reported. Columbia has not identified all adjustments necessary to conform Pacific Premier's accounting policies to Columbia's accounting policies. Although the merger has closed, Columbia is in the process of performing a more detailed review. As a result of that review, differences could be identified between the accounting policies of the two companies that, when conformed, could have a material impact on the combined company's financial information.

The table below represents a summary of reclassification adjustments made to conform the presentation of Pacific Premier's income statement for the six months ended June 30, 2025 and the year ended December 31, 2024 to that of Columbia:

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| | | | |
|:---|:---|:---|:---|
| **Income Statement**<br>**(dollars in thousands)** | **Income Statement**<br>**(dollars in thousands)** | **June 30, 2025** | **December 31, 2024** |
| **1** | Adjustment to interest income |  |  |
|  | &nbsp;&nbsp;&nbsp;Interest and dividends on investment securities | $(15929) | $(52650) |
|  | &nbsp;&nbsp;&nbsp;Interest on temporary investments and interest bearing deposits | 15929 | 52650 |
|  | Reclassified Pacific Premier's interest on temporary investments and interest-bearing deposits to interest and dividends on investment securities to align with Columbia's financial presentation. |  |  |
| **2** | Adjustments to non-interest expense line items |  |  |
|  | &nbsp;&nbsp;&nbsp;Salaries and employee benefits | $2357 | $4960 |
|  | &nbsp;&nbsp;&nbsp;Occupancy and equipment, net | 15521 | 29669 |
|  | &nbsp;&nbsp;&nbsp;Other expenses | (17878) | (34629) |
|  | Reclassified benefit related expenses and software-related costs from other expenses to salaries and employee benefits, and occupancy and equipment, net, respectively, to align with Columbia's financial presentation. |  |  |

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**Note 4—Transaction Accounting Adjustments** 

The following transaction accounting adjustments have been reflected in the unaudited pro forma financial information. All adjustments are based on current assumptions and valuations, which are subject to change.

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| | | |
|:---|:---|:---|
| **Balance Sheet**<br>**(dollars in thousands)** | **Balance Sheet**<br>**(dollars in thousands)** | **June 30, 2025** |
| **A** | Adjustment to cash and cash equivalents |  |
|  | &nbsp;&nbsp;&nbsp;To reflect cash paid for merger-related expenses. | $(185000) |
|  | Merger-related expenses of $115 million are expected to be incurred for change in control agreements, retention, investment banker fees, legal fees and accounting fees. Additionally, other accounting and audit related costs, contract and lease terminations, marketing, and other expenses in connection with the merger, of $70 million are reflected in the unaudited pro forma combined condensed balance sheet. |  |
| **B** | Adjustment to investment securities, held to maturity |  |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated fair value of acquired investment securities. | $(310000) |

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| | | |
|:---|:---|:---|
| **Balance Sheet**<br>**(dollars in thousands)** | **Balance Sheet**<br>**(dollars in thousands)** | **June 30, 2025** |
| **C** | Adjustments to loans and leases |  |
|  | &nbsp;&nbsp;&nbsp;To reverse existing fair value mark on Pacific Premier acquired loans. | $25000 |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated fair value related to current interest rates and liquidity on acquired loans and leases. | (449000) |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated lifetime credit losses on acquired loans and leases. | (96000) |
|  | &nbsp;&nbsp;&nbsp;Net fair value pro forma adjustments | (520000) |
|  | &nbsp;&nbsp;&nbsp;Gross up of purchase credit deteriorated ("PCD") loans and leases for credit mark. | 48000 |
|  |  | $(472000) |
| **D** | Adjustments to allowance for credit losses on loans and leases |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate Pacific Premier allowance for credit losses on loans and leases at closing date as the credit risk is contemplated in the fair value adjustments. | $170663 |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated lifetime credit losses on acquired PCD loans and leases. | (48000) |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated lifetime credit losses on acquired non-PCD loans and leases. | (48000) |
|  |  | $74663 |
| **E** | Adjustment to premises and equipment, net |  |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated fair value of acquired premises and equipment. | $12000 |
| **F** | Adjustments to goodwill |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate Pacific Premier goodwill at closing date. | $(901312) |
|  | &nbsp;&nbsp;&nbsp;To record the goodwill associated with the mergers. See Note 2. | 502179 |
|  |  | $(399133) |
| **G** | Adjustments to other intangible assets, net |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate Pacific Premier other intangible assets, net. | $(27127) |
|  | &nbsp;&nbsp;&nbsp;To record the estimated fair value of acquired identifiable core deposit intangible assets, calculated as 3.3% of Pacific Premier core deposits. | 413759 |
|  |  | $386632 |
| **H** | Adjustments to deferred tax asset, net |  |
|  | &nbsp;&nbsp;&nbsp;To reflect deferred tax asset created in the mergers, which is calculated as follows: |  |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustment to investment securities, held to maturity | (310000) |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustments to loans and leases, net | (349337) |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustment to premises and equipment, net | 12000 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustments to other intangible assets, net | 386632 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustment to deposits | (7000) |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Adjustment to junior and other subordinated debentures, at amortized cost | 1000 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Subtotal for fair value adjustments | (266705) |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Calculated deferred tax asset at estimated combined statutory federal and state income tax rate of 26.5% | 70677 |
|  | &nbsp;&nbsp;&nbsp;To reflect deferred tax asset created on provision for credit losses on Pacific Premier's non-PCD loans. | 12720 |
|  | &nbsp;&nbsp;&nbsp;To reflect change in taxes receivable due to deductible portion of merger expenses. | 39220 |
|  |  | $122617 |
| **I** | Adjustment to deposits |  |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated fair value based on current market rates for similar products. | $7000 |

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| | | |
|:---|:---|:---|
| **Balance Sheet**<br>**(dollars in thousands)** | **Balance Sheet**<br>**(dollars in thousands)** | **June 30, 2025** |
| **J** | Adjustment to junior and other subordinated debentures, at amortized cost |  |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated fair value at closing date based on current market rates and spreads for similar subordinated debentures. | $(1000) |
| **K** | Adjustments to common stock |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate historical Pacific Premier common stock. | $(2401498) |
|  | &nbsp;&nbsp;&nbsp;To reflect the closing-date fair value of the consideration transferred by Columbia for its interest in Pacific Premier. See Note 2. | 2409624 |
|  |  | $8126 |
| **L** | Adjustments to accumulated deficit/retained earnings |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate historical Pacific Premier retained earnings. | $(639189) |
|  | &nbsp;&nbsp;&nbsp;To adjust for estimated lifetime credit losses on acquired non-PCD loans and leases on an after tax basis. | (35280) |
|  | &nbsp;&nbsp;&nbsp;To adjust for after tax merger expenses. | (145780) |
|  |  | $(820249) |
| **M** | Adjustment to accumulated other comprehensive income |  |
|  | &nbsp;&nbsp;&nbsp;To eliminate historical Pacific Premier accumulated other comprehensive income. | $65269 |

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| | | | |
|:---|:---|:---|:---|
| **Income Statement**<br>**(dollars and shares in thousands)** | **Income Statement**<br>**(dollars and shares in thousands)** | **Six Months Ended June 30, 2025** | **Year Ended December 31, 2024** |
| **N** | Adjustment to interest and fees on loans and leases |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect accretion of loan rate premium and non-PCD credit discount resulting from loans and leases fair value using sum of years digits method to approximate effective yield method over the estimated lives of the acquired loan portfolio, which is approximately 4.2 years. | $83028 | $208155 |
| **O** | Adjustment to interest and dividends on investment securities |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect estimated accretion of the discount on acquired investment securities fair value using sum of years digits method to approximate effective yield method over the estimated lives of the acquired investment securities portfolios, which is approximately 15.4 years. | $23961 | $50467 |
| **P** | Adjustment to interest on deposits |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect amortization of deposit discount resulting from deposit fair value based on weighted average life of time deposits being approximately one year. | $— | $(7000) |
| **Q** | Adjustment to interest on junior and other subordinated debentures |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect accretion of subordinated debenture premium resulting from subordinated debenture fair value based on the life of subordinated debenture of approximately four years. | $125 | $250 |
| **R** | Adjustment to provision for credit losses |  |  |
|  | &nbsp;&nbsp;&nbsp;To record provision for credit losses on Pacific Premier's non-purchase credit deteriorated loans. | $— | $48000 |

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| | | | |
|:---|:---|:---|:---|
| **Income Statement**<br>**(dollars and shares in thousands)** | **Income Statement**<br>**(dollars and shares in thousands)** | **Six Months Ended June 30, 2025** | **Year Ended December 31, 2024** |
| **S** | Adjustments to intangible amortization |  |  |
|  | &nbsp;&nbsp;&nbsp;To remove Pacific Premier intangible assets amortization | $(5067) | $(11091) |
|  | &nbsp;&nbsp;&nbsp;To reflect amortization of acquired intangible assets fair value based on amortization period of 10 years and using the sum-of-the-years-digits method of amortization. | 33853 | 75229 |
|  |  | $28786 | $64138 |
| **T** | Adjustment to other expenses |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect the pre-tax nonrecurring merger-related costs expected to be incurred as a result of the acquisition and assuming such costs are incurred after closing of the acquisition. | $— | $185000 |
| **U** | Adjustment to income tax provision |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect the income tax effect of pro forma adjustments at the estimated combined statutory federal and state income tax rate of 26.5%. | $20691 | $(8418) |
| **V** | Adjustments to weighted average number of common shares outstanding - Basic |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect acquisition of Pacific Premier basic common shares. | (94932) | (94579) |
|  | &nbsp;&nbsp;&nbsp;To reflect the par value of 88,916 shares of Columbia common stock to be issued in the mergers. | 88916 | 88916 |
|  |  | (6016) | (5663) |
| **W** | Adjustments to weighted average number of common shares outstanding - Diluted |  |  |
|  | &nbsp;&nbsp;&nbsp;To reflect acquisition of Pacific Premier diluted common shares. | (94968) | (94683) |
|  | &nbsp;&nbsp;&nbsp;To reflect issuance of 88,916 shares of Columbia common stock in connection with the mergers. See Note 2. | 88916 | 88916 |
|  |  | (6052) | (5767) |

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