Byline Bancorp, Inc.
US ˙ NYSE ˙ US1244111092

SecurityBY / Byline Bancorp, Inc.
InstitutionBoston Partners
Latest Disclosed Ownership918,449 shares
Latest Disclosed Value $ 29,067,153
Boston Partners reports 29.96% increase in ownership of BY / Byline Bancorp, Inc.

On May 11, 2026 - Boston Partners filed a 13F-HR form disclosing ownership of 918,449 shares of Byline Bancorp, Inc. (US:BY) valued at $28,995,435 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 706,741 shares of Byline Bancorp, Inc.. This represents a change in shares of 29.96% during the quarter. The current value of the position is $30,070,020 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)
2026-05-11 2026-03-31 13F BYLINE BANCORP COM 124411109 918,449 211,708 29.96 29,067 40.49 0.0130
2026-02-13 2025-12-31 13F BYLINE BANCORP COM 124411109 706,741 -26,064 -3.56 20,690 1.82 0.0214
2025-11-13 2025-09-30 13F BYLINE BANCORP COM 124411109 732,805 341 0.05 20,320 4.21 0.0209
2025-08-12 2025-06-30 13F/A-1 BYLINE BANCORP COM 124411109 732,464 13,818 1.92 19,500 4.62 0.0217
2025-08-07 2025-06-30 13F BYLINE BANCORP COM 124411109 732,464 13,818 19,500 0.0090
2025-05-13 2025-03-31 13F BYLINE BANCORP COM 124411109 718,646 -3,649 -0.51 18,638 -10.56 0.0225
2025-02-11 2024-12-31 13F BYLINE BANCORP COM 124411109 722,295 643,628 818.17 20,839 889.98 0.0253
2024-11-12 2024-09-30 13F BYLINE BANCORP COM 124411109 78,667 -6,953 -8.12 2,106 3.59 0.0025
2024-08-14 2024-06-30 13F BYLINE BANCORP COM 124411109 85,620 -4,551 -5.05 2,033 3.78 0.0025
2024-05-28 2024-03-31 13F/A-1 BYLINE BANCORP COM 124411109 90,171 -25,076 -21.76 1,959 -27.88 0.0023
2024-05-13 2024-03-31 13F BYLINE BANCORP COM 124411109 90,171 -25,076 1,959 0.0010
2024-02-07 2023-12-31 13F BYLINE BANCORP COM 124411109 115,247 -22,239 -16.18 2,715 0.22 0.0036
2023-11-08 2023-09-30 13F BYLINE BANCORP COM 124411109 137,486 -18,844 -12.05 2,710 -4.21 0.0038
2023-08-10 2023-06-30 13F BYLINE BANCORP COM 124411109 156,330 -6,832 -4.19 2,828 -19.82 0.0038
2023-05-09 2023-03-31 13F BYLINE BANCORP COM 124411109 163,162 -6,975 -4.10 3,528 -9.75 0.0048
2023-02-08 2022-12-31 13F BYLINE BANCORP COM 124411109 170,137 131,945 345.48 3,908 405.56 0.0053
2022-11-09 2022-09-30 13F BYLINE BANCORP COM 124411109 38,192 420 1.11 773 -14.02 0.0011
2022-08-10 2022-06-30 13F BYLINE BANCORP COM 124411109 37,772 -4,020 -9.62 899 -19.37 0.0013
2022-05-10 2022-03-31 13F BYLINE BANCORP COM 124411109 41,792 0 0.00 1,115 -2.45 0.0014
2022-02-04 2021-12-31 13F BYLINE BANCORP COM 124411109 41,792 0 0.00 1,143 11.40 0.0014
2021-11-05 2021-09-30 13F BYLINE BANCORP COM 124411109 41,792 -6,571 -13.59 1,026 -6.22 0.0013
2021-08-12 2021-06-30 13F BYLINE BANCORP COM 124411109 48,363 -38,154 -44.10 1,094 -40.22 0.0014
2021-05-10 2021-03-31 13F BYLINE BANCORP COM 124411109 86,517 0 0.00 1,830 36.87 0.0025
2021-02-10 2020-12-31 13F/A-1 BYLINE BANCORP COM 124411109 86,517 19,338 28.79 1,337 76.39 0.0021
2021-02-04 2020-12-31 13F BYLINE BANCORP COM 124411109 86,517 19,338 1,337 802.1205
2020-11-13 2020-09-30 13F/A-1 BYLINE BANCORP COM 124411109 67,179 -30,878 -31.49 758 -40.97 0.0014
2020-11-09 2020-09-30 13F BYLINE BANCORP COM 124411109 98,057 0 1,284 942.6090
2020-08-12 2020-06-30 13F BYLINE BANCORP COM 124411109 98,057 15,598 18.92 1,284 50.00 0.0024
2020-05-13 2020-03-31 13F BYLINE BANCORP COM 124411109 82,459 -8,495 -9.34 856 -51.91 0.0017
2020-02-06 2019-12-31 13F/A-1 BYLINE BANCORP COM 124411109 90,954 13,854 17.97 1,780 29.08 0.0024
2020-02-05 2019-12-31 13F BYLINE BANCORP COM 124411109 90,954 13,854 1,780 1,000.7680
2019-11-20 2019-09-30 13F/A-1 BYLINE BANCORP COM 124411109 77,100 0 0.00 1,379 -6.45 0.0019
2019-11-08 2019-09-30 13F BYLINE BANCORP COM 124411109 77,100 0 1,474 0.0019
2019-08-26 2019-06-30 13F/A-1 BYLINE BANCORP COM 124411109 77,100 0 0.00 1,474 3.44 0.0019
2019-08-09 2019-06-30 13F BYLINE BANCORP COM 124411109 77,100 0 1,474
2019-05-13 2019-03-31 13F/A-1 BYLINE BANCORP COM 124411109 77,100 -50,000 -39.34 1,425 -32.69 0.0019
2019-05-03 2019-03-31 13F BYLINE BANCORP COM 124411109 77,100 -50,000 1,425
2019-02-07 2018-12-31 13F BYLINE BANCORP COM 124411109 127,100 -4,000 -3.05 2,117 -28.86 0.0030
2018-11-14 2018-09-30 13F BYLINE BANCORP COM 124411109 131,100 -7,100 -5.14 2,976 -3.60 0.0035
2018-08-03 2018-06-30 13F BYLINE BANCORP COM 124411109 138,200 1,800 1.32 3,087 -1.31 0.0037
2018-05-04 2018-03-31 13F BYLINE BANCORP COM 124411109 136,400 2,500 1.87 3,128 1.69 0.0038
2018-02-14 2017-12-31 13F/A-1 BYLINE BANCORP COM 124411109 133,900 35,400 35.94 3,076 46.90 0.0036
2018-02-01 2017-12-31 13F BYLINE BANCORP COM 124411109 133,900 35,400 3,076
2017-11-02 2017-09-30 13F BYLINE BANCORP COM 124411109 98,500 98,500 2,094 0.0026
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.