<SEC-DOCUMENT>0001567619-21-002574-index.html : 20210209
<SEC-HEADER>0001567619-21-002574.hdr.sgml : 20210209
<ACCEPTANCE-DATETIME>20210209144828
ACCESSION NUMBER:		0001567619-21-002574
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20210209
DATE AS OF CHANGE:		20210209
GROUP MEMBERS:		BANC FUND IX L.P.
GROUP MEMBERS:		BANC FUND VIII L.P.

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OLD SECOND BANCORP INC
		CENTRAL INDEX KEY:			0000357173
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				363143493
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-33870
		FILM NUMBER:		21605785

	BUSINESS ADDRESS:	
		STREET 1:		37 S RIVER ST
		CITY:			AURORA
		STATE:			IL
		ZIP:			60507
		BUSINESS PHONE:		6308920202

	MAIL ADDRESS:	
		STREET 1:		37 SOUTH RIVER STREET
		CITY:			AURORA
		STATE:			IL
		ZIP:			60507

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BANC FUNDS CO LLC
		CENTRAL INDEX KEY:			0001029311
		IRS NUMBER:				364134318
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		20 NORTH WACKER DRIVE
		STREET 2:		SUITE 3300
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3128554067

	MAIL ADDRESS:	
		STREET 1:		20 NORTH WACKER DRIVE
		STREET 2:		SUITE 3300
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BANC FUND IV L P
		DATE OF NAME CHANGE:	19961218
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>doc1.htm
<DESCRIPTION>NONE
<TEXT>
Document 1 - file: doc1.htm

</DOCUMENT>
</SEC-DOCUMENT>