SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Ladowicz John (Last) (First) (Middle) 37 S. RIVER ST. (Street) AURORA IL 60506 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol OLD SECOND BANCORP INC [ OSBC ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 09/19/2017
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Old Second Bancorp, Inc. Common Stock	09/19/2017		S		700	A	$12.1	256,627(1)	I	IRA
Old Second Bancorp, Inc. Common Stock	09/19/2017		S		700	D	$12.105	257,327	I	IRA
Old Second Bancorp, Inc. Common Stock	09/19/2017		S		650	D	$12.1524	258,027	I	IRA
Old Second Bancorp, Inc. Common Stock	09/19/2017		S		2,000	D	$12.1525	258,677	I	IRA
Old Second Bancorp, Inc. Common Stock	09/19/2017		S		7,000	D	$12.15	260,677	I	IRA
Old Second Bancorp, Inc. Common Stock	09/18/2017		S		2,450	D	$12.15	9,750	I	co-trustee with spouse
Old Second Bancorp, Inc. Common Stock								12,146(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option Right to Buy	$7.49							02/17/2010	02/17/2019	Common Stock	1,500		1,500	D

Explanation of Responses:

1. Included in this total are 242,200 shares held by Mr. Ladowicz in a ROTH IRA account and 14,427 shares held in Trust in an IRA account.

2. Included in this total are 4,646 shares in Mr. Ladowicz' name outright and 7,500 shares of restricted stock units in Mr. Ladowicz' name.

	/s/ John Ladowicz	09/19/2017
	** 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 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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