SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* SECOND CURVE CAPITAL LLC (Last) (First) (Middle) 237 PARK AVENUE 9TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 03/31/2011	3. Issuer Name and Ticker or Trading Symbol MERCANTILE BANK CORP [ MBWM ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	904,439(1)	I	By advisory clients of Second Curve Capital, LLC

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* SECOND CURVE CAPITAL LLC (Last) (First) (Middle) 237 PARK AVENUE 9TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BROWN THOMAS K (Last) (First) (Middle) C/O SECOND CURVE CAPITAL, LLC 237 PARK AVENUE, 9TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. These securities may be deemed to be beneficially owned by Second Curve Capital, LLC and Thomas K. Brown. Second Curve Capital, LLC is the investment manager of Second Curve Partners, LP, Second Curve Partners II, LP, Second Curve Partners International, Ltd., Second Curve Opportunity Fund, LP, Second Curve Opportunity Fund II, LP, Second Curve Opportunity Fund International, Ltd., Second Curve Vision Fund, LP, and Second Curve Vision Fund International, Ltd. Thomas K. Brown is the managing member of Second Curve Capital, LLC. Each such Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his or its pecuniary interest therein, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

	Second Curve Capital, LLC By: /s/ Thomas K. Brown, Its Managing Member	04/05/2011
	Thomas K. Brown By: /s/ Thomas K. Brown	04/05/2011
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
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