Bruce Booth

Director Bruce Booth sells 31,798 shares (31.8K) at $103.75 blended average under 10b5-1 plan; stock down 5.3% from 52-week high but up 26.1% in 30 days.

Bruce Booth sold 31,798 shares across 4 separate transactions on 2026-06-22 at prices of $103.42 and $104.38, realizing $3,299,037.16, pursuant to a pre-arranged 10b5-1 trading plan. As a scheduled sale, this transaction carries no timing signal. Booth retains 613,762 shares post-transaction, representing a 4.9% reduction from his pre-transaction holdings. The company reported $34.4M quarterly revenue with $-69.2M net income, negative annual growth of -16.7%, and remains unprofitable, yet the stock has appreciated 26.1% over the past 30 days and 33.6% over 90 days. Booth's prior sales at KYMR show mixed historical returns: three sales posted negative 30- and 90-day returns (ranging from -5.8% to -18.0%), while his cross-ticker track record across 20 prior sales averaged -10.6% over 30 days and -4.5% over 90 days. The substantial rally following recent execution warrants attention to whether valuation has decoupled from fundamentals.

Director Bruce Booth sold 478,198 shares (~43.6% of holdings) for $45.3M via 10b5-1 plan; retains 617.7K shares plus 28,127 options.

Bruce Booth executed 29 separate sales totaling 478,198 shares for $45,293,293.82 across June 17–22, 2026, reducing his non-derivative holdings from 1,095,861 shares to 617,663 shares. This represents a -43.6% reduction in his common stock position, though he retains 28,127 stock options. Critically, this activity was conducted under a pre-arranged 10b5-1 trading plan adopted on 2025-12-16, meaning the sales were scheduled and non-discretionary rather than responsive to current market conditions. The company remains unprofitable with annual revenue growth of -16.7% and a net loss of $-69,234,000 in the most recent full fiscal year, though the stock has appreciated +26.1% over the past 30 days and +33.6% over 90 days. Booth's prior sales at KYMR (5 trades) showed negative returns on average at 30 and 90 days post-transaction, but the pre-arranged nature of this sale prevents attribution of timing discretion to the insider.

Director Bruce Booth sold 81.9K shares at $90.13, totaling $7.4M; stock now trading at $86.11 amid -16.7% revenue decline

Director Bruce Booth executed 2 separate sales totaling 81,866 shares for $7,378,582.58 at $90.13 per share, reducing his holdings by 10.8% to 675,341 shares. The sales occurred near the 52-week high of $95.03, with the stock currently trading $86.11—a 4.5% decline from transaction price. Notably, at KYMR specifically, Booth's 5 prior trades (all sales from December 2025) have shown consistent underperformance on 30-day horizons (ranging -16.2% to -18.0%), with his cross-ticker track record showing a 0.00% well-timed rate on sells (meaning none of his 20 prior open-market sales have been followed by stock declines). The company backdrop is concerning: latest quarterly revenue stands at $2,764,000.00 with a net loss of $-82,175,000.00, and annual revenue growth is -16.7%, yet the company maintains a $7.0B market cap while unprofitable. This disparity between valuation, deteriorating fundamentals, and director selling near recent highs warrants scrutiny of whether Booth is recognizing execution or valuation risks ahead of broader market repricing.

Director Bruce Booth sold 236,588 shares ($21.7M) across 14 transactions on 2025-12-10/12, reducing stake by 25.7%

Director Bruce Booth executed 14 separate sales totaling 236,588 shares for $21,699,043.80 on December 10–12, 2025, at prices ranging from $88.64 to $93.20—a blended average price of $91.72. This represents a substantial 25.7% reduction in his holdings, from 921,981 shares to 685,393 shares post-transaction. The sales occurred within the stock's 52-week range near its recent peak of $94.30, capturing prices in the upper tier of year-to-date movement. Contextually, Kymera Therapeutics is an unprofitable company with a latest-quarter revenue of $2,764,000.00 and a full-year net income of $-82,175,000.00, along with annual revenue contraction of -40.1%. The scale of this single-director exit—$21.7M in gross proceeds—represents a material reduction in insider stake at a company facing significant financial headwinds.

Director Booth Bruce sold 88,878 shares for $3,041,683.18 at SION on 2025-10-21; stock at 52-week high $42.50 (+83.7% in 30d)

Director Booth Bruce executed 10 separate sales totaling 88,878 shares for $3,041,683.18 on 2025-10-21, reducing his position by 11.5% to 686,567 shares remaining. The transactions occurred across a narrow price range ($32.69–$36.42 blended to $34.22), and notably coincide with the stock trading at its 52-week high of $42.50 following an 83.7% surge in the prior 30 days and 115.0% gain over 90 days. The company is unprofitable (net income −$18,068,000.00) with a market cap of $1,875,942,477.50. This filing also follows four prior sell transactions by the same insider on 2025-10-20 and one on 2025-10-17, indicating a sustained reduction in exposure over a concentrated window. With the stock at an elevated valuation peak after significant recent appreciation and the insider's sale executed at substantially lower prices than the current market level, this cluster of sales warrants investor scrutiny of the company's operational outlook and any material developments that may inform the timing of these dispositions.

Director Booth Bruce sold 286,369 shares for $9,251,102.06 in 18 transactions over 2025-10-16 to 2025-10-20

Booth Bruce, a director at Sionna Therapeutics, executed 18 separate sales totaling 286,369 shares for $9,251,102.06 across three trading days (October 16–20, 2025), reducing his holdings by 29.0% from 988,354 shares to 702,000 shares. The sales occurred at prices ranging from $30.15 to $33.38, with a blended average of $32.30, very close to the current price of $32.20 and within 1.6% of the 52-week high of $32.72. This large, multi-tranche disposition of nearly 290,000 shares represents a material reduction in insider ownership. The company is currently unprofitable (net income $-18,068,000.00) with a market cap of $1.4B; the context of a substantial equity reduction by an insider during a period where the stock has appreciated 39.2% over 30 days and 69.3% over 90 days merits investor attention, particularly given the company's negative earnings profile.

Director Booth Bruce sold 194,932 shares (20.6% of holdings) for $5,939,783.84 across 12 transactions Oct 10–15 at avg $30.47.

Booth Bruce, a director at Sionna Therapeutics, executed 12 separate sales totaling 194,932 shares for $5,939,783.84 between October 10–15, 2025, at a blended average price of $30.47—at the current 52-week high of $30.91. This represents a 20.6% reduction in his post-transaction holdings to 751,664 shares. The timing follows a sharp 68.6% run-up over 90 days and a 38.6% gain over 30 days, coinciding with a recent cluster of five prior SION trades (all sells) executed on October 1, 3, and 6. Against this context of sustained upward momentum, the magnitude of this 194.9K-share disposal and the multi-tranche execution pattern across several days signal a material capital redeployment at an elevated price level. The company remains unprofitable with net income of $-18,068,000.00, adding relevance to insider liquidity actions at peak valuations.

Director Booth Bruce sold 49,546 shares at $29.99 avg (Oct 3–6) for $1,485,790, reducing stake by 5.9% amid +19.2% 30-day surge.

Bruce sold 4 separate tranches totaling 49,546 shares for $1,485,790 at an average price of $29.99, executed Oct 3–6. The timing is notable: the stock has surged +19.2% over the past 30 days and +36.7% over 90 days, now trading at $28.61, only 4.7% below its 52-week high of $30.01. The sales occurred near the peak of this recent rally, with transaction prices ($29.95–$30.00) at or within 0.4% of the 52-week high. Bruce's cross-ticker track record shows 19 prior sells with a 23.08% well-timed rate (90-day negative returns after sale), but his same-ticker history at SION consists of 5 prior sells in late September, all too recent to have measurable outcomes. The underlying company is unprofitable (net income of $-18,068,000) with a market cap of $1,262,840,336.03, providing context that fundamentals may warrant caution alongside the price momentum that framed these sales.

Director Booth Bruce sold 78,693 shares (78.7K) for $2.4M at avg $30.08, reducing stake by 9.0%; stock now at $28.47

Director Booth Bruce executed 6 separate sales totaling 78,693 shares for $2,367,472.73 across three trading dates (Sept 29–Oct 1), at a blended average price of $30.08. His holdings fell from 872.8K to 794.1K shares (a 9.0% reduction). The sales occurred near the 52-week high of $29.52—the current price of $28.47 is 3.6% below that peak, and the stock has rallied 15.6% over 30 days and 34.4% over 90 days. His cross-ticker track record shows 19 prior sells with a 47.37% well-timed rate (and +0.8% average 30-day return after sells), while at SION specifically, his only prior trade was a buy on 2025-02-10 that returned -31.6% over 90 days. The company reported net income of -$18.1M against a $1.3B market cap, indicating ongoing losses. This filing merits deeper review to understand the economic context and any scheduled trading arrangements, given the substantial dollar volume executed near a recent high.

Director Booth Bruce bought 60,000 shares of SION at $18.00 ($1.1M) amid 5 other insider purchases in 14 days

Booth Bruce, as a director of Sionna Therapeutics, purchased 60,000 shares at $18.00 on 2025-02-10, increasing his holdings from 747.7K to 807.7K shares (an 8.0% increase). The purchase occurred at a 19% discount to the current price of $22.24, just 2 trading days after the company's recent listing. Notably, a cluster of 5 other insiders also bought within the same 14-day window, suggesting coordinated conviction across the leadership team at or near IPO pricing. The transaction involves derivative securities conversion per Form 4 Table II; the 60,000 shares represent a partial position adjustment within broader holdings, not a complete stake shift. This multi-insider accumulation pattern in the immediate post-listing period warrants monitoring as evidence of management's early alignment with the newly public capital structure.