BY BYLINE BANCORP, INC. Insider Trading

Director Mary Jo S. Herseth purchases 300 BY shares at $30.83; stock down 8.9% from 52-week high.

Director Mary Jo S. Herseth purchased 300 shares of BYLINE BANCORP, INC. at $30.83 on 2026-03-16, increasing her holdings from 18,500 to 18,800 shares. At current price of $30.55, the stock trades 8.9% below its 52-week high of $33.52 and has declined 7.1% over the past 30 days. Herseth's prior trading history at this ticker is mixed: of 5 previous buys, 3 achieved positive 90-day returns, though her most recent purchase on 2025-06-13 posted strong results (90d +14.5%) while an earlier buy on 2025-03-06 declined 11.2% over 30 days. The company trades at a P/E of 10.32 with $37.2M in net income and a $1.4B market cap. This purchase occurs amid modest recent weakness but within the stock's established trading range.

General Counsel Doran Brian F buys 750 BY shares at $33.13; first open-market purchase in role.

Doran Brian F, as General Counsel, executed a first-time open-market purchase of 750 shares at $33.13 on 2026-02-17, establishing an initial stake in BYLINE BANCORP. The transaction occurs near the company's 52-week high of $33.52, with the stock up 24.0% over the prior 90 days and 8.0% over 30 days. At a market cap of $1.5B and P/E of 12.06, the company trades at modest valuation multiples relative to earnings of $37.2M. As an opening position for a General Counsel, this purchase establishes a direct financial alignment with the company but does not yet indicate a pattern of accumulation or conviction.

Director Phillip R. Cabrera purchased 169 shares of Byline Bancorp at $31.03 on 2026-01-28, increasing holdings to 4,129 shares.

Cabrera purchased 169 shares at $31.03, raising his stake by 4.3% to 4,129 shares. The stock has appreciated 8.6% over the past 30 days and 19.1% over 90 days, trading at $31.84—near its 52-week high of $31.88. His prior buy at this ticker on 2025-06-11 generated positive 90-day returns of 16.6%, and his cross-ticker track record shows 1 prior buy with average 90-day returns of 16.6% and a 100% win rate. The company trades at a P/E of 11.58 with a market cap of $1.5B and net income of $37.2M, providing fundamentals context for the position.

BYLINE BANCORP: Abraham Thomas (President, SBC) sells 23,400 shares (37.6% reduction) for $629,146.70

Abraham Thomas, President of SBC at Byline Bancorp, executed 2 separate sales totaling 23,400 shares for $629,146.70 on 2025-10-28, reducing his post-transaction holdings to 38,882 shares from 62,282 shares (a 37.6% reduction in his position). The blended average sale price of $26.89 is modestly below the current price of $26.94, and the stock is trading 16.0% below its 52-week high of $32.06. With a P/E of 10.40 and market cap of $1.2B, this represents a substantial reduction in personal exposure at levels near the recent price floor (52-week low of $23.25). The significance is moderate: the transaction is large in absolute terms and relative to his holdings, but there is insufficient information regarding scheduling (10b5-1 plan status) or prior trading patterns at this ticker to characterize the transaction's timing or strategic intent.

Director William Kistner buys 65 BY shares at $27.56; held 14,089 post-transaction; P/E 10.55.

Director William Kistner purchased 65 shares of Byline Bancorp at $27.56 on 2025-10-28, increasing his holdings from 14,024 to 14,089 shares. The transaction is modest in absolute size ($1,791.24) and represents a 0.5% increase in his position. In his same-ticker history at BY, Kistner's prior four measurable buys show mixed outcomes: two generated positive 90-day returns (+14.6%, +14.4%), while two yielded negative 90-day returns (-7.4%, -2.4%), suggesting his decision-making at this ticker has been inconsistent. The stock currently trades at $27.32, down 3.6% over 30 days and -14.8% from its 52-week high of $32.06, placing the purchase slightly below recent momentum but amid a broader decline. With a P/E of 10.55 and market cap of $1,253,029,778.32, Byline remains a relatively inexpensive regional bank, though the timing pattern at this ticker offers no clear directional signal.

Director Kistner buys 60 BY shares at $25.70; modest $1.5K purchase extends 5-buy pattern at 50% same-ticker win rate.

Director William G Kistner purchased 60 shares of Byline Bancorp at $25.70 on 2025-08-08, a small open-market acquisition valued at $1,542.30 that raised his holdings to 14,024 shares. His prior trades at this ticker show a mixed record: 2 of 4 prior buys delivered positive 90-day returns (+10.5% and +12.6%, +15.4%), while the other 2 resulted in declines (-10.0%, -4.4%, -6.4%). His cross-ticker track record shows slightly better success (57.14% 90-day win rate with avg 90d return +4.0%), but same-ticker timing at Byline Bancorp has been inconsistent. The stock is currently down 6.9% over 30 days and 18.8% from its 52-week high of $32.06, trading at $26.02; the valuation remains reasonable with a P/E of 10.05 and market cap of $1.2B.

Director Kent Steven P. buys 4,125 shares of BY at $24.75; joins 5-insider cluster buy in 14 days; +20.2% at 90d on prior identical buy.

Director KENT STEVEN P. purchased 4,125 shares at $24.75 on 2025-06-11, adding to holdings that now total 71,750 shares. This buy coincides with a cluster pattern: 5 other insiders also purchased within the past 14 days, suggesting coordinated confidence at current valuations. Critically, KENT's prior buy at this same ticker on 2024-06-06 generated a +20.2% 90-day return, and his cross-ticker track record shows 3 prior buys with a 100.00% 90-day win rate (avg +12.2% return). At current price of $25.21—-21.4% from the 52-week high and -6.8% over 30 days—the stock is trading at a P/E of 9.81 on $28.2M net income. The convergence of cluster activity, a proven prior buy pattern at this ticker, and multi-insider participation within two weeks signals concentrated insider conviction despite recent price weakness.

Director Del Valle purchases 40,808 shares of BY at $24.75 ($1.0M); 5 prior buys all well-timed; cluster buying detected

Del Valle Perochena Antonio, a director, purchased 40,808 shares of Byline Bancorp at $24.75 on 2025-06-11, representing entry into a new position worth $1,009,998.00. His prior trading history at BY shows a decisive pattern: all 5 prior buys were well-timed, with 90-day returns ranging from +9.5% to +19.2%, indicating strong accuracy in identifying opportune purchase points at this ticker. The current stock price of $25.21 is -21.4% from the 52-week high and has declined -6.8% over the past 30 days, positioning this purchase near depressed levels relative to recent trading range. Additionally, 5 other insiders have also bought within the past 14 days, forming a cluster buy pattern that may suggest coordinated confidence in the stock's value at current levels. With a P/E of 9.81 and net income of $28,248,000.00, the company's valuation metrics remain conservative.

Director HERSETH MARY JO S. bought 2,000 shares of BYLINE BANCORP at $25.33; 5 insiders bought within 14 days (cluster pattern).

HERSETH MARY JO S. purchased 2,000 shares at $25.33 on 2025-06-13, increasing her holdings to 18,500 shares (+12.1% vs pre-transaction holdings). The stock has declined 21.4% from its 52-week high of $32.06 and is down 6.8% over the past 30 days. At the same ticker (BY), her prior buy on 2025-03-06 resulted in a 30-day loss of 11.2% and a 90-day loss of 5.0%, though her earlier purchases in 2024 and 2023 showed mixed outcomes with 2 of 4 prior buys achieving positive 90-day returns. Most notably, a cluster of 5 other insiders also bought within the past 14 days, suggesting coordinated director interest at current price levels despite recent weakness. The company trades at a P/E of 9.81 with net income of $28,248,000.00, indicating fundamental valuation metrics remain compressed relative to the recent decline.

CEO Herencia bought 4,040 shares at $24.75; 5 other insiders bought within 14 days

Roberto Herencia, CEO of Byline Bancorp, purchased 4,040 shares at $24.75 on 2025-06-11, increasing holdings from 322,729 to 326,769 shares. This transaction occurred within a cluster of 5 other insider buys over the prior 14 days, suggesting coordinated accumulation at this price level. The stock has declined 6.8% over 30 days and 5.1% over 90 days, trading 21.4% below its 52-week high. Herencia's cross-ticker track record shows 2 prior buys with mixed results (avg 30d return +2.0%, avg 90d return -5.8%), indicating his prior open-market purchases have not consistently preceded near-term gains.