8-K/A

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 (Date of earliest event reported): April 30, 2010

Chemical Financial Corporation
(Exact Name of Registrant as
Specified in its Charter)

Michigan
(State or Other Jurisdiction
of Incorporation) 000-08185
(Commission
File Number) 38-2022454
(IRS Employer
Identification No.)

235 E. Main Street
Midland, Michigan
(Address of Principal Executive Offices)
48640
(Zip Code)

Registrant's telephone number, including area code:  (989) 839-5350

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 (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Explanatory Note

                    Chemical Financial Corporation (the "Company") is filing this Form 8-K/A as an amendment to its Current Report on Form 8-K filed on May 3, 2010 (the "Initial Report"), disclosing the previously announced acquisition ("Acquisition") of O.A.K. Financial Corporation ("OAK") pursuant to an Agreement and Plan of Merger, dated as of January 7, 2010 (the "Plan of Merger"). As previously disclosed, the Acquisition was completed and became effective on April 30, 2010. This Current Report on Form 8-K/A is being filed to provide the pro forma financial statements described under Item 9.01(b) below, in accordance with the requirements of Item 9.01 of Form 8-K.

Item 2.01 Completion of Acquisition or Disposition of Assets.

                    The information set forth under Item 2.01 of the Initial Report is incorporated herein by reference.

Item 9.01.	Financial Statements and Exhibits.
	(a)	Financial Statements of Businesses Acquired
		The financial statements required by Item 9.01(a) of Form 8-K are included under Part II, Item 8 of O.A.K. Financial Corporation's Annual Report on Form 10-K filed with the Commission on February 12, 2010, and are here incorporated by reference.
	(b)	Pro Forma Financial Information
	(i)	The pro forma condensed statement of income for the year ended December 31, 2009 required by Item 9.01(b) of Form 8-K is included in the registrant's Amendment No. 1 to Form S-4 Registration Statement filed with the Commission on March 8, 2010, and is here incorporated by reference.
	(ii)	The pro forma condensed statement of position at March 31, 2010 and pro forma condensed statement of income for the three months ended March 31, 2010 are attached as Exhibit 99.1 to this Current Report and are here incorporated by reference.
	(d)	Exhibits:
	2.1	Agreement and Plan of Merger, dated January 7, 2010. Previously filed as Exhibit 2.1 to the registrant's Current Report on Form 8-K dated January 7, 2010, filed with the SEC on January 8, 2010. Here incorporated by reference.

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SIGNATURES

                    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.

Dated:	May 3, 2010	CHEMICAL FINANCIAL CORPORATION (Registrant)
		/s/ Lori A. Gwizdala
		Lori A. Gwizdala      Executive Vice President, Chief Financial      Officer and Treasurer

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EXHIBIT INDEX

Exhibit Number	Document
2.1	Agreement and Plan of Merger, dated January 7, 2010. Previously filed as Exhibit 2.1 to the registrant's Current Report on Form 8-K dated January 7, 2010, filed with the SEC on January 8, 2010. Here incorporated by reference.
99.1	Pro forma condensed statement of position at March 31, 2010 and pro forma condensed statement of income as of March 31, 2010.

EX-99.1

EXHIBIT 99.1

UNAUDITED PRO FORMA COMBINED FINANCIAL INFORMATION

On April 30, 2010, Chemical Financial Corporation (Chemical or CHFC) and O.A.K. Financial Corporation (OAK) completed the merger in which OAK merged with and into Chemical, with Chemical as the surviving corporation. The following unaudited pro forma combined balance sheet as of March 31, 2010 and the unaudited pro forma combined income statement for the three months ended March 31, 2010, have been prepared to reflect the merger of OAK into Chemical as if the merger had occurred on March 31, 2010, with respect to the balance sheet, and as of January 1, 2010, with respect to the income statement, in each case giving effect to the pro forma adjustments described in the accompanying notes. Merger and integration costs incurred and further expected to be incurred in conjunction with this transaction are not included in the pro forma income statement.

The pro forma adjustments are based on estimates made for the purpose of preparing this pro forma financial information. The actual adjustments to the accounts will be made based on the underlying historical financial data and their respective fair values at April 30, 2010. The purchase price was computed based on Chemical's closing stock price of $23.70 per share on April 30, 2010, the date the merger was consummated. Chemical's management believes that the estimates used in this pro forma financial information are reasonable under the circumstances. However, numerous circumstances, including changes in interest rates or changes in economic conditions within the State of Michigan, could cause actual fair values at April 30, 2010 to be significantly different than the fair values used in this pro forma financial information. Chemical has engaged a valuation specialist to assist in the process of developing fair values as of April 30, 2010 for financial reporting purposes.

The unaudited pro forma combined financial information has been prepared based on the acquisition method of accounting found in Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 805 - Business Combinations (ASC 805), with 3,530,129 shares of Chemical common stock issued in the merger, subject to adjustment in certain limited circumstances. In addition, 26,425 stock options were issued by Chemical in exchange for vested stock options outstanding at OAK. In accordance with ASC 805, the purchase price is allocated to OAK assets and liabilities acquired using their estimated fair value values as of March 31, 2010.

The unaudited pro forma combined balance sheet as of March 31, 2010 is not necessarily indicative of the combined financial position had the merger been effective at that date. The unaudited pro forma combined income statement is not necessarily indicative of the results of operations that would have occurred had the merger been effective at the beginning of the period indicated, or of the future results of operations of Chemical. This pro forma financial information should be read in conjunction with historical financial statements and the related notes of Chemical and OAK previously filed with the Securities and Exchange Commission.

This pro forma financial information does not include the effects of any potential cost savings which management believes could result after the completion of the merger. In addition, subsequent to the merger completion date, there may be further refinements of the purchase price allocation as additional information becomes available.

Chemical Financial Corporation and O.A.K. Financial Corporation
Pro Forma Combined Balance Sheets
March 31, 2010
(Unaudited)

	CHFC			OKFC			Pro Forma Adjustments				Pro Forma
	(Dollar amounts in thousands, except per share data)
Assets
Cash and cash equivalents	$	447,371		$	22,468		$	(4,702	)	(1)	$	450,137
								(15,000	)	(2)
Investment securities		690,716			73,988			-				764,704
Other securities		22,128			5,321			-				27,449
Loans held-for-sale		4,943			1,727			-				6,670
Total loans		2,988,315			686,783			(44,305	)	(3)		3,630,793
Allowance for loan losses		(84,155	)		(15,522	)		15,522		(4)		(84,155	)
Net loans		2,904,160			671,261			(28,783	)			3,546,638
Premises and equipment, net		54,438			14,769			-				69,207
Goodwill		69,908			-			30,339		(5)		100,247
Other intangible assets		5,242			180			10,402		(6)		15,824
Interest receivable and other assets		93,723			22,124			10,335		(7)		126,182
Total Assets	$	4,292,629		$	811,838		$	2,591			$	5,107,058
Liabilities and Shareholders' Equity
Deposits:
Noninterest-bearing	$	558,470		$	80,546		$	-			$	639,016
Interest-bearing		2,915,869			610,608			3,332		(8)		3,514,809
								(15,000	)	(2)
Total deposits		3,474,339			691,154			(11,668	)			4,153,825
Interest payable and other liabilities		28,264			4,455			2,700		(9)		35,419
Short-term borrowings		237,712			5,600			-				243,312
Federal Home Loan Bank (FHLB) advances		80,000			40,190			1,858		(8)		122,048
Total liabilities		3,820,315			741,399			(7,110	)			4,554,604
Shareholders' equity:
Preferred stock, no par value		-			-			-				-
Common stock, $1 par value per share:		23,903			2,703			(2,703	)	(10)		27,433
								3,530		(11)
Additional paid-in capital		348,136			32,778			(32,778	)	(10)		428,308
								80,172		(11)
Retained earnings		112,900			32,437			(32,437	)	(10)		109,338
								(3,562	)	(1)
Accumulated other comprehensive income (loss)		(12,625	)		2,521			(2,521	)	(10)		(12,625	)
Total shareholders' equity		472,314			70,439			9,701				552,454
Total Liabilities and Shareholders' Equity	$	4,292,629		$	811,838		$	2,591			$	5,107,058
Book value per share	$	19.76		$	26.06						$	20.14
Tangible book value per share		16.74			26.05							16.03

(1)	Reflects legal, accounting, financial advisory and other non-recurring costs directly attributable to the closing of the transaction which are not expected to have a continuing impact on operations, and therefore, are not included in the Pro Forma Combined Income Statement.
(2)	Eliminate intercompany cash deposit balances.
(3)	Adjust loans acquired from OAK to estimated fair value, including both an interest rate component and a credit component for estimated inherent losses within OAK's loan portfolio.
(4)	Reverse allowance for loan losses for OAK as credit risk is included in the estimated fair value adjustment in (3) above.
(5)	Recognize goodwill after adjusting acquired assets and liabilities of OAK to estimated fair value.
(6)	Recognize estimated fair value of core deposit intangible (CDI) asset associated with OAK's deposit liabilities assumed. Also recognize estimated fair value of noncompete agreements and acquired mortgage servicing rights.
(7)	Recognition of net deferred tax asset for estimated fair value adjustments at 35%.
(8)	Adjust fixed-rate interest-bearing deposit liabilities and FHLB borrowings to estimated fair value based on discounted future cash flows.
(9)	Adjust for recognition of certain change of control agreements as acquired liabilities of OAK.
(10)	Eliminate equity of OAK.
(11)	Adjust for issuance of 3,530,129 shares of CHFC common stock (based on April 30, 2010 market price per share of Chemical of $23.70) plus estimated fair value of stock options issued.

Chemical Financial Corporation and O.A.K. Financial Corporation
Pro Forma Combined Income Statement
Three-Month Period Ended March 31, 2010
(Unaudited)

	CHFC		OKFC			Pro Forma Adjustments				Pro Forma
	(Dollar amounts in thousands, except per share data)
Interest income	$	46,122	$	9,441		$	639		(12)	$	56,202
Interest expense		9,734		2,908			(938	)	(13)		11,704
Net interest income		36,388		6,533			1,577				44,498
Provision for loan losses		14,000		2,800			-				16,800
Net interest income after provision for loan losses		22,388		3,733			1,577				27,698
Noninterest income		9,440		2,071			-				11,511
Operating expenses		29,189		5,890			528		(14)		34,567
							(1,040	)	(15)
Income (loss) before income taxes		2,639		(86	)		2,089				4,642
Federal income tax expense (benefit)		350		(190	)		940		(16)		1,100
Net income	$	2,289	$	104		$	1,149			$	3,542
Net income per common share:
Basic	$	0.10	$	0.04						$	0.13
Diluted		0.10		0.04							0.13
Weighted average shares outstanding:
Basic		23,903		2,703			3,530		(17)		27,433
Diluted		23,921		2,703			3,530		(17)		27,451

(12)	Adjust for accretion attributable to estimated fair value to loans.
(13)	Adjust for premium amortization attributable to fixed-rate interest-bearing deposit liabilities and FHLB borrowings.
(14)	Adjust for amortization of core deposit intangible over a period of 10 years on an accelerated basis. Also adjust for amortization of noncompete agreements and mortgage servicing rights.
(15)	Adjust for nonrecurring transaction related expenses included in the first quarter of 2010 income statements of CHFC and OAK.
(16)	Recognize the tax impact of pro forma acquisition adjustments at 35%, net of nondeductible acquisition expenses.
(17)	Pro forma shares computed by multiplying the merger exchange ratio of 1.306 shares by OAK's 2.703 million shares outstanding.