<SEC-DOCUMENT>0001104659-25-037832-index.html : 20250423
<SEC-HEADER>0001104659-25-037832.hdr.sgml : 20250423
<ACCEPTANCE-DATETIME>20250423113337
ACCESSION NUMBER:		0001104659-25-037832
CONFORMED SUBMISSION TYPE:	S-4
PUBLIC DOCUMENT COUNT:		14
FILED AS OF DATE:		20250423
DATE AS OF CHANGE:		20250423

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OLD SECOND BANCORP INC
		CENTRAL INDEX KEY:			0000357173
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		ORGANIZATION NAME:           	02 Finance
		EIN:				363143493
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-4
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-286687
		FILM NUMBER:		25859842

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-4
<SEQUENCE>1
<FILENAME>tm2511100-1_s4.htm
<DESCRIPTION>S-4
<TEXT>
Document 1 - file: tm2511100-1_s4.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>tm2511100d2_ex5-1.htm
<DESCRIPTION>EXHIBIT 5.1
<TEXT>
Document 2 - file: tm2511100d2_ex5-1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>tm2511100d2_ex23-1.htm
<DESCRIPTION>EXHIBIT 23.1
<TEXT>
Document 3 - file: tm2511100d2_ex23-1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.2
<SEQUENCE>4
<FILENAME>tm2511100d2_ex23-2.htm
<DESCRIPTION>EXHIBIT 23.2
<TEXT>
Document 4 - file: tm2511100d2_ex23-2.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>5
<FILENAME>tm2511100d2_ex99-1.htm
<DESCRIPTION>EXHIBIT 99.1
<TEXT>
Document 5 - file: tm2511100d2_ex99-1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.2
<SEQUENCE>6
<FILENAME>tm2511100d2_ex99-2.htm
<DESCRIPTION>EXHIBIT 99.2
<TEXT>
Document 6 - file: tm2511100d2_ex99-2.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-FILING FEES
<SEQUENCE>7
<FILENAME>tm2511100d2_ex-filingfees.htm
<DESCRIPTION>EX-FILING FEES
<TEXT>
Document 7 - file: tm2511100d2_ex-filingfees.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>8
<FILENAME>lg_bancorpfinancial-4clr.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 8 - file: lg_bancorpfinancial-4clr.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>9
<FILENAME>lg_kbw-4c.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 9 - file: lg_kbw-4c.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>10
<FILENAME>lg_oldsecondbancorp-4c.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 10 - file: lg_oldsecondbancorp-4c.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>11
<FILENAME>lg_rsm-4c.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 11 - file: lg_rsm-4c.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>12
<FILENAME>tm2511100d2_ex5-1mg001.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 12 - file: tm2511100d2_ex5-1mg001.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>13
<FILENAME>tm2511100d2_ex99-1img01.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 13 - file: tm2511100d2_ex99-1img01.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>14
<FILENAME>tm2511100d2_ex99-1img02.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 14 - file: tm2511100d2_ex99-1img02.jpg

</DOCUMENT>
</SEC-DOCUMENT>