Old Second Bancorp, Inc.
DE ˙ DB ˙ US6802771005
18,10 € ↑0,30 (1,69%)
2026-06-03
DEL PRIS
SecurityDE:OSB / Old Second Bancorp, Inc.
InstitutionBlackRock, Inc.
Latest Disclosed Ownership3,503,897 shares
Ownership 7.80%
BlackRock, Inc. ownership in OSB / Old Second Bancorp, Inc.

2024-01-26 - BlackRock, Inc. has filed an SC 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 3,503,897 shares of Old Second Bancorp, Inc. (DE:OSB). This represents 7.8 percent ownership of the company. In their previous filing dated 2023-01-31 , BlackRock, Inc. had reported owning 3,269,868 shares, indicating an increase of 7.16 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date		Effective
Date		Form Prev
Shares		 Latest
Shares		 ΔShares
(Percent)		 Ownership
(Percent)		 ΔOwnership
(Percent)
2024-01-26 2024-01-26 13G/A 3,269,868 3,503,897 7.16 7.80 6.85
2023-01-31 2023-01-31 13G 2,173,725 3,269,868 50.43 7.30 48.98
2022-04-08 2022-04-08 13G/A 1,994,301 2,173,725 9.00 4.90 -28.99
2022-02-01 2022-02-01 13G/A 2,164,781 1,994,301 -7.88 6.90 -6.76
2021-01-29 2021-01-29 13G/A 2,056,294 2,164,781 5.28 7.40 7.25
2020-02-05 2020-02-05 13G/A 2,051,586 2,056,294 0.23 6.90 0.00
2019-02-06 2019-02-06 13G/A 1,940,774 2,051,586 5.71 6.90 4.55
2018-01-29 2018-01-29 13G/A 1,869,504 1,940,774 3.81 6.60 4.76
2017-01-25 2017-01-25 13G/A 1,628,725 1,869,504 14.78 6.30 14.55
2016-01-28 2016-01-28 13G 1,628,725 5.50

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F OLD SECOND BANCORP INC DEL COM 680277100 4,126,244 -29,662 -0.71 83,185 2.65 0.0001
2026-02-12 2025-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 4,155,906 338,128 8.86 81,040 22.81 0.0014
2025-11-12 2025-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,817,778 316,180 9.03 65,990 6.23 0.0012
2025-08-12 2025-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,501,598 -78,899 -2.20 62,118 4.26 0.0012
2025-05-02 2025-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,580,497 43,040 1.22 59,579 -5.27 0.0013
2025-02-07 2024-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,537,457 -142,662 -3.88 62,896 9.62 0.0013
2024-11-13 2024-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,680,119 243,305 7.08 57,373 12.72 0.0012
2024-08-13 2024-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,436,814 121,822 3.67 50,899 10.94 0.0012
2024-05-10 2024-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,314,992 -188,905 -5.39 45,879 -15.20 0.0011
2024-02-13 2023-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,503,897 326,223 10.27 54,100 25.09 0.0014
2023-11-13 2023-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,177,674 -160,800 -4.82 43,248 -0.81 0.0012
2023-08-11 2023-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,338,474 21,443 0.65 43,600 -6.51 0.0012
2023-05-12 2023-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,317,031 47,163 1.44 46,637 -11.08 0.0014
2023-02-13 2022-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 3,269,868 158,312 5.09 52,449 29.16 0.0016
2022-11-14 2022-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,111,556 -7,253 -0.23 40,608 -2.68 0.0014
2022-08-12 2022-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 3,118,809 945,084 43.48 41,728 32.30 0.0013
2022-05-12 2022-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,173,725 179,424 9.00 31,541 25.61 0.0008
2022-02-10 2021-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 1,994,301 -21,858 -1.08 25,110 -4.64 0.0006
2021-11-09 2021-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,016,159 -119,407 -5.59 26,331 -0.57 0.0007
2021-08-11 2021-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,135,566 -200,465 -8.58 26,481 -14.18 0.0007
2021-05-07 2021-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,336,031 171,250 7.91 30,858 41.12 0.0009
2021-02-05 2020-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,164,781 79,006 3.79 21,866 39.88 0.0007
2020-11-06 2020-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,085,775 -57,627 -2.69 15,632 -6.26 0.0006
2020-08-14 2020-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,143,402 81,975 3.98 16,676 17.07 0.0007
2020-05-01 2020-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,061,427 5,133 0.25 14,245 -48.57 0.0007
2020-02-13 2019-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,056,294 548 0.03 27,698 10.26 0.0011
2019-11-08 2019-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,055,746 4,824 0.24 25,121 -4.08 0.0011
2019-08-22 2019-06-30 13F/A-1 OLD SECOND BANCORP INC ILL COM 680277100 2,050,922 -13,184 -0.64 26,190 0.78 0.0011
2019-08-13 2019-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,050,922 -13,184 26,190
2019-05-09 2019-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,064,106 12,520 0.61 25,987 -2.56 0.0012
2019-02-08 2018-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 2,051,586 39,292 1.95 26,671 -14.21 0.0013
2018-11-09 2018-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 2,012,294 35,505 1.80 31,089 9.21 0.0013
2018-08-09 2018-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 1,976,789 69,773 3.66 28,466 7.39 0.0013
2018-05-09 2018-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 1,907,016 -33,758 -1.74 26,507 0.06 0.0013
2018-02-09 2017-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 1,940,774 28,031 1.47 26,492 2.98 0.0013
2017-11-14 2017-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 1,912,743 28,240 1.50 25,726 18.20 0.0013
2017-08-10 2017-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 1,884,503 58,451 3.20 21,765 5.95 0.0012
2017-05-12 2017-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 1,826,052 1,821,170 37,303.77 20,542 37,940.74 0.0011
2017-02-10 2016-12-31 13F OLD SECOND BANCORP INC ILL COM 680277100 4,882 0 0.00 54 31.71 0.0001
2016-11-08 2016-09-30 13F OLD SECOND BANCORP INC ILL COM 680277100 4,882 0 0.00 41 24.24 0.0001
2016-08-10 2016-06-30 13F OLD SECOND BANCORP INC ILL COM 680277100 4,882 3,853 374.44 33 371.43 0.0000
2016-05-10 2016-03-31 13F OLD SECOND BANCORP INC ILL COM 680277100 1,029 1,029 7 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.