Old Second Bancorp, Inc.
DE ˙ DB ˙ US6802771005
18,20 € ↑0,60 (3,41%)
2026-06-05
DEL PRIS
SecurityDE:OSB / Old Second Bancorp, Inc.
InstitutionBnp Paribas Arbitrage, Sa
Latest Disclosed Ownership13,750 shares
Latest Disclosed Value $ 277,200
Bnp Paribas Arbitrage, Sa reports 13.08% increase in ownership of OSB / Old Second Bancorp, Inc.

On May 12, 2026 - Bnp Paribas Arbitrage, Sa filed a 13F-HR form disclosing ownership of 13,750 shares of Old Second Bancorp, Inc. (DE:OSB) valued at $235,125 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 12,160 shares of Old Second Bancorp, Inc.. This represents a change in shares of 13.08% during the quarter. The current value of the position is $250,250 USD.

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)
2026-05-12 2026-03-31 13F Old Second Bancorp Equity 680277100 13,750 1,590 13.08 277 16.88 0.0000
2026-02-10 2025-12-31 13F Old Second Bancorp Equity 680277100 12,160 -4,182 -25.59 237 -15.96 0.0001
2025-11-13 2025-09-30 13F Old Second Bancorp Equity 680277100 16,342 -7,564 -31.64 282 -33.49 0.0002
2025-08-14 2025-06-30 13F Old Second Bancorp Equity 680277100 23,906 -30,001 -55.65 424 -52.73 0.0002
2025-05-14 2025-03-31 13F Old Second Bancorp Equity 680277100 53,907 5,645 11.70 897 4.55 0.0005
2025-02-14 2024-12-31 13F Old Second Bancorp Equity 680277100 48,262 15,295 46.39 858 67.25 0.0005
2024-11-13 2024-09-30 13F Old Second Bancorp Equity 680277100 32,967 24,084 271.12 514 291.60 0.0003
2024-08-13 2024-06-30 13F Old Second Bancorp Equity 680277100 8,883 -12,974 -59.36 132 -56.62 0.0001
2024-05-01 2024-03-31 13F Old Second Bancorp Equity 680277100 21,857 8,661 65.63 303 48.77 0.0003
2024-02-14 2023-12-31 13F/A-2 Old Second Bancorp Equity 680277100 13,196 -8,373 -38.82 204 -30.72 0.0002
2024-02-07 2023-12-31 13F/A-1 Old Second Bancorp Equity 680277100 13,196 -8,373 204 0.0000
2024-02-07 2023-12-31 13F Old Second Bancorp Equity 680277100 13,196 204
2023-11-14 2023-09-30 13F Old Second Bancorp Equity 680277100 21,569 8,773 68.56 294 75.45 0.0004
2023-08-09 2023-06-30 13F Old Second Bancorp Equity 680277100 12,796 -12,113 -48.63 167 -52.29 0.0002
2023-05-12 2023-03-31 13F OLD SECOND BANCORP EQUITY 680277100 24,909 13,405 116.52 350 90.22 0.0005
2023-02-14 2022-12-31 13F Old Second Bancorp Equity 680277100 11,504 -7,124 -38.24 185 -24.28 0.0003
2022-11-16 2022-09-30 13F/A-1 Old Second Bancorp Equity 680277100 18,628 5,030 36.99 243 34.25 0.0004
2022-11-15 2022-09-30 13F Old Second Bancorp Equity 680277100 18,628 5,030 243 0.0001
2022-08-12 2022-06-30 13F Old Second Bancorp Equity 680277100 13,598 10,761 379.31 182 341.46 0.0003
2022-05-18 2022-03-31 13F/A-1 Old Second Bancorp Equity 680277100 2,837 -10,001 -77.90 41 -74.53 0.0001
2022-02-09 2021-12-31 13F OLD SECOND BANCORP EQUITY 680277100 12,838 5,328 70.95 162 64.29 0.0002
2021-11-16 2021-09-30 13F/A-1 OLD SECOND BANCORP EQUITY 680277100 7,510 3,997 113.78 98 127.91 0.0001
2021-11-12 2021-09-30 13F OLD SECOND BANCORP EQUITY 680277100 7,283 3,770 55 0.0000
2021-08-10 2021-06-30 13F OLD SECOND BANCORP EQUITY 680277100 3,513 -9,703 -73.42 44 -75.29 0.0001
2021-05-07 2021-03-31 13F OLD SECOND BANCORP EQUITY 680277100 13,216 5,394 68.96 175 120.25 0.0003
2021-02-10 2020-12-31 13F OLD SECOND BANCORP EQUITY 680277100 7,822 539 7.40 79 46.30 0.0001
2020-10-30 2020-09-30 13F OLD SECOND BANCORP EQUITY 680277100 7,283 5,635 341.93 55 350.00 0.0001
2020-08-06 2020-06-30 13F OLD SECOND BANCORP EQUITY 680277100 1,648 -7,296 -81.57 13 -80.33 0.0000
2020-05-13 2020-03-31 13F OLD SECOND BANCORP EQUITY 680277100 8,944 2,008 28.95 62 -34.41 0.0001
2020-02-12 2019-12-31 13F OLD SECOND BANCORP EQUITY 680277100 6,936 2,300 49.61 93 66.07 0.0002
2019-11-07 2019-09-30 13F OLD SECOND BANCORP EQUITY 680277100 4,636 40 0.87 57 -3.45 0.0001
2019-07-30 2019-06-30 13F OLD SECOND BANCORP EQUITY 680277100 4,596 -1,450 -23.98 59 -23.68 0.0001
2019-04-25 2019-03-31 13F OLD SECOND BANCORP EQUITY 680277100 6,046 5,038 499.80 76 484.62 0.0002
2019-02-12 2018-12-31 13F OLD SECOND BANCORP EQUITY 680277100 1,008 9 0.90 13 -13.33 0.0000
2018-11-07 2018-09-30 13F OLD SECOND BANCORP EQUITY 680277100 999 0 0.00 15 7.14 0.0000
2018-07-25 2018-06-30 13F OLD SECOND BANCORP EQUITY 680277100 999 -5,093 -83.60 14 -83.33 0.0000
2018-05-11 2018-03-31 13F OLD SECOND BANCORP EQUITY 680277100 6,092 -2,408 -28.33 85 -27.59 0.0002
2018-03-05 2017-12-31 13F/A-1 OLD SECOND BANCORP EQUITY 680277100 8,500 5,429 176.78 116 182.93 0.0002
2018-02-01 2017-12-31 13F OLD SECOND BANCORP EQUITY 680277100 8,500 5,429 116
2017-11-03 2017-09-30 13F OLD SECOND BANCORP INC ILL STOCK 680277100 3,071 -221 -6.71 41 7.89 0.0001
2017-08-03 2017-06-30 13F OLD SECOND BANCORP INC ILL STOCK 680277100 3,292 3,057 1,300.85 38 1,800.00 0.0001
2017-05-03 2017-03-31 13F OLD SECOND BANCORP INC ILL STOCK 680277100 235 -275 -53.92 3 -60.00 0.0000
2017-02-14 2016-12-31 13F OLD SECOND BANCORP INC ILL STOCK 680277100 510 -1,434 -73.77 6 -68.75 0.0000
2016-10-05 2016-09-30 13F * OLD SECOND BANCORP INC ILL COM STOCK 680277100 1,944 835 75.29 16 128.57 0.0001
2016-07-06 2016-06-30 13F * OLD SECOND BANCORP INC ILL COM STOCK 680277100 1,109 1,109 0.00 8 0.0000
2016-04-22 2016-03-31 13F * OLD SECOND BANCORP INC ILL COM STOCK 680277100 0 -2,722 -100.00 0 -100.00
2016-04-19 2015-12-31 13F/A-1 * OLD SECOND BANCORP INC ILL COM STOCK 680277100 2,722 -3,809 -58.32 21 -47.50 0.0001
2016-02-10 2015-12-31 13F * OLD SECOND BANCORP INC ILL COM STOCK 680277100 2,722 21
2015-11-13 2015-09-30 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 6,531 4,079 166.35 41 150.00 0.0001
2015-08-14 2015-06-30 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 2,452 2,451 245,100.00 16 269,616.67 0.0000
2015-05-15 2015-03-31 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0 0.00 0 20.00 0.0000
2015-03-10 2014-12-31 13F/A-1 OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0 0.00 0 0.00 0.0000
2015-02-11 2014-12-31 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0
2014-11-12 2014-09-30 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0 0.00 0 -100.00 0.0000
2014-08-14 2014-06-30 13F/A-1 OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0 0.00 0 -100.00 0.0000
2014-08-14 2014-06-30 13F OLD SECOND BANCORP INC ILL COM STOCK 680277100 1 0
2014-05-13 2014-03-31 13F OLD SECOND BANCORP INC ILL STOCK 680277100 1 0 0.00 0 0.00 0.0000
2014-04-02 2013-12-31 13F/A-1 OLD SECOND BANCORP INC ILL STOCK 680277100 1 1 0 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.