Atlas funds tied to Kymera (KYMR) sell 478,198 shares in June
Filing Impact
Filing Sentiment
Form Type
4
Rhea-AI Filing Summary
Kymera Therapeutics director‑associated entities reported sizeable June stock sales alongside an option exercise. Across June 17–22, entities linked to Bruce Booth sold a net 478,198 shares of Kymera common stock in open‑market transactions at prices generally around the low‑ to low‑$100 range.
Most shares are held directly by Atlas Venture Fund X and Atlas Venture Opportunity Fund I; Booth is a member of their general partners and disclaims Section 16 beneficial ownership beyond any pecuniary interest. On June 17, he exercised stock options for 11,741 shares at $20.00 per share and sold all those shares at a weighted‑average price of $89.98, leaving no direct common‑stock holdings but 28,127 fully vested options outstanding that expire on August 19, 2030. Several sales were executed under Rule 10b5‑1 trading plans adopted in December 2025.
Positive
- None.
Negative
- None.
Insights
Large, pre‑planned fund sales and a routine option exercise form a net‑sell pattern.
Entities associated with Bruce Booth, a director of Kymera Therapeutics, reported net sales of 478,198 shares of common stock over June 17–22, 2026, all via open‑market transactions. Most activity reflects portfolio moves by Atlas Venture Fund X and Atlas Venture Opportunity Fund I, which directly hold the shares.
The filing shows a typical exercise‑and‑sell for Booth personally: he exercised options for 11,741 shares at $20.00 and sold all at a weighted‑average $89.98. Afterward, he held no direct common shares but retained 28,127 fully vested options expiring in 2030. Footnotes state several trades were under Rule 10b5‑1 plans adopted in December 2025, suggesting the timing was pre‑scheduled rather than reactive. Overall, this appears as sizeable but planned selling by venture funds plus a routine monetization of options, with no additional guidance on future intentions.
Insider Trade Summary 10b5-1
Net Seller: 478,198 shares ($45,293,294)
Net Sell
31 txns
Insider
Booth Bruce
Role
null
Sold
478,198 shs ($45.29M)
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 14,921 | $92.14 | $1.37M |
| Sale | Common Stock | 2,035 | $94.48 | $192K |
| Sale | Common Stock | 11,783 | $95.12 | $1.12M |
| Sale | Common Stock | 20,903 | $96.24 | $2.01M |
| Sale | Common Stock | 16,084 | $97.68 | $1.57M |
| Sale | Common Stock | 25,976 | $98.58 | $2.56M |
| Sale | Common Stock | 52,442 | $99.57 | $5.22M |
| Sale | Common Stock | 56,348 | $100.17 | $5.64M |
| Sale | Common Stock | 6,597 | $101.61 | $670K |
| Sale | Common Stock | 8,990 | $102.48 | $921K |
| Sale | Common Stock | 2,179 | $92.14 | $201K |
| Sale | Common Stock | 286 | $94.48 | $27K |
| Sale | Common Stock | 1,648 | $95.12 | $157K |
| Sale | Common Stock | 2,919 | $96.24 | $281K |
| Sale | Common Stock | 2,247 | $97.68 | $219K |
| Sale | Common Stock | 3,603 | $98.58 | $355K |
| Sale | Common Stock | 7,319 | $99.57 | $729K |
| Sale | Common Stock | 7,879 | $100.17 | $789K |
| Sale | Common Stock | 918 | $101.61 | $93K |
| Sale | Common Stock | 1,253 | $102.48 | $128K |
| Sale | Common Stock | 62,897 | $90.48 | $5.69M |
| Sale | Common Stock | 32,359 | $91.85 | $2.97M |
| Sale | Common Stock | 5,672 | $92.16 | $523K |
| Sale | Common Stock | 8,809 | $90.48 | $797K |
| Sale | Common Stock | 4,526 | $91.85 | $416K |
| Sale | Common Stock | 793 | $92.16 | $73K |
| Exercise | Stock Option (Right to Buy) | 11,741 | $0.00 | -- |
| Exercise | Common Stock | 11,741 | $20.00 | $235K |
| Sale | Common Stock | 11,741 | $89.98 | $1.06M |
| Sale | Common Stock | 92,169 | $90.38 | $8.33M |
| Sale | Common Stock | 12,902 | $90.38 | $1.17M |
Holdings After Transaction:
Common Stock — 3,691,811 shares (Indirect, See footnote);
Stock Option (Right to Buy) — 28,127 shares (Direct, null);
Common Stock — 11,741 shares (Direct, null)
Footnotes (1)
- This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 16, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $89.95 to $90.20 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold each separate price within the ranges set forth in footnotes (2), (4) and (7) through (19). This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund X, L.P. and Atlas Venture Opportunity Fund I, L.P. on December 11, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $90.05 to $91.03 inclusive. These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any. The shares are owned directly by Atlas Venture Opportunity Fund I, L.P. ("AVOF"). Atlas Venture Associates Opportunity I, L.P. ("AVAO LP") is the general partner of AVOF. Atlas Venture Associates Opportunity I, LLC ("AVAO LLC") is the general partner of AVAO LP. The Reporting Person is a member of AVAO LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF, except to the extent of his pecuniary interest therein, if any. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $90.05 to $91.04 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $91.10 to $92.085 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $92.1191 to $92.2833 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $92.11 to $92.50 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $93.93 to $94.91 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $94.99 to $95.76 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $96.00 to $96.959 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $97.0018 to $97.99 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $98.00 to $98.9997 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $99.00 to $99.9942 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $100.00 to $100.8925 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $101.00 to $101.98 inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $102.01 to $103.00 inclusive. Fully vested and exercisable.
Key Figures
Net shares sold: 478,198 shares
Option exercise shares: 11,741 shares
Option exercise price: $20.00/share
+3 more
6 metrics
Net shares sold
478,198 shares
Net open‑market sales across June 17–22, 2026
Option exercise shares
11,741 shares
Common shares acquired via option exercise on June 17, 2026
Option exercise price
$20.00/share
Strike price for 11,741 exercised options
Sale price for exercised shares
$89.98/share
Weighted‑average sale price for 11,741 exercised shares
Remaining options
28,127 options
Fully vested options held after transactions
Option expiration
August 19, 2030
Expiration date for remaining stock options
Key Terms
Rule 10b5-1 trading plan, weighted average price, Section 16 beneficial ownership, Stock Option (Right to Buy), +1 more
5 terms
Rule 10b5-1 trading plan regulatory
"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 16, 2025."
A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.
weighted average price financial
"The price reported in Column 4 is a weighted average price."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
Section 16 beneficial ownership regulatory
"The Reporting Person is a member of AVA X LLC and disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any."
Stock Option (Right to Buy) financial
"security_title": "Stock Option (Right to Buy)""
pecuniary interest financial
"disclaims Section 16 beneficial ownership of such securities held by AVOF, except to the extent of his pecuniary interest therein, if any."
FAQ
Did Bruce Booth personally exercise Kymera Therapeutics (KYMR) stock options in this filing?
Yes. Bruce Booth exercised options for 11,741 Kymera common shares at $20.00 per share. He then sold all 11,741 shares at a weighted‑average price of $89.98, leaving him with no direct shares but remaining vested options.
How many Kymera Therapeutics (KYMR) stock options does Bruce Booth still hold after these transactions?
After the reported transactions, Bruce Booth holds 28,127 Kymera stock options. According to the filing, these options are fully vested and exercisable and are scheduled to expire on August 19, 2030, if not exercised earlier.
Were the Kymera Therapeutics (KYMR) insider sales made under a Rule 10b5-1 plan?
Yes, several sales were executed pursuant to Rule 10b5-1 trading plans. The filing notes plans adopted in December 2025 by Bruce Booth and by Atlas venture funds, indicating these transactions were pre‑arranged rather than opportunistic market‑timing.
What price range did the Kymera Therapeutics (KYMR) insider sales cover in this Form 4?
The reported Kymera sales occurred at various weighted‑average prices, with specific ranges such as $89.95 to $90.20 and up to about $103.00. Each block represents multiple trades within those ranges across several trading days in June 2026.