Cullinan CSO sells 8,000 shares, exercises 4,000
Cullinan Therapeutics’ chief scientific officer exercised options and sold 8,000 CGEM shares under a pre-arranged Rule 10b5-1 trading plan.
Rhea-AI Filing Summary
Cullinan Therapeutics, Inc. (CGEM) reported that Chief Scientific Officer Jennifer Michaelson exercised stock options and sold shares on September 8, 2026. She exercised options to acquire 4,000 shares of common stock at an exercise price of $4.30 per share, leaving 78,987 shares underlying options outstanding. On the same date she sold 8,000 shares of common stock at a weighted average price of $21.57 per share in multiple trades between $21.31 and $21.83, under a Rule 10b5-1 trading plan adopted on August 7, 2025.
Positive
- None.
Negative
- None.
Insider Trade Summary 10b5-1
Exercise and sale activity reported; no spread calculated
Exercise and Sale
3 txns
Insider
Michaelson Jennifer
Role
Chief Scientific Officer
Sold
8,000 shs ($173K)
Approx. gross sale proceeds
$173K
Approx. exercise cost
$17K
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Exercise | Stock Option (Right to Buy) F3 | 4,000 | $0.00 | $0.00 |
| Exercise | Common Stock | 4,000 | $4.30 | $17K |
| Sale | Common Stock F1, F2 | 8,000 | $21.57 | $173K |
Holdings After Transaction:
Stock Option (Right to Buy) — 78,987 contracts (Direct);
Common Stock — 158,844 shares (Direct)
Footnotes (3)
- F1. Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 on August 7, 2025.
- F2. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $21.31 to $21.83. The Reporting Person undertakes to provide to the Issuer, any shareholder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
- F3. 25% of the shares vested on July 4, 2020, and the remaining shares vested in 36 equal monthly installments thereafter.
Key Figures
Shares sold: 8,000 shares
Weighted average sale price: $21.57 per share
Option exercise shares: 4,000 shares
+4 more
7 metrics
Shares sold
8,000 shares
Common stock sale reported for September 8, 2026
Weighted average sale price
$21.57 per share
Common stock sold in multiple trades between $21.31 and $21.83
Option exercise shares
4,000 shares
Shares acquired by exercising stock options on September 8, 2026
Option exercise price
$4.30 per share
Exercise price for the 4,000-share stock option exercise
Remaining option underlying shares
78,987 shares
Shares of common stock underlying options after the reported exercise
Option expiration date
October 28, 2030
Expiration date of the stock option from which 4,000 shares were exercised
Rule 10b5-1 plan adoption date
August 7, 2025
Date the trading plan governing the share sale was established
Key Terms
Rule 10b5-1, weighted average price, stock options
3 terms
Rule 10b5-1 regulatory
"Transaction effected pursuant to a plan established pursuant to Rule 10b5-1"
Rule 10b5-1 is a regulation that allows company insiders to buy or sell their shares at predetermined times, even if they have access to non-public information. It acts like setting a schedule in advance for transactions, helping prevent accusations of unfair trading. This rule provides a way for insiders to plan trades transparently, giving investors confidence that these transactions are not based on hidden information.
weighted average price financial
"The price reported is a weighted average price; shares sold in multiple transactions"
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.
stock options financial
"The reporting person exercised stock options to acquire 4,000 shares of common stock"
Stock options are agreements that give a person the right to buy or sell a company's stock at a specific price within a certain time frame. They are often used as a reward or incentive, similar to a coupon that can be used later if the stock price rises, allowing the holder to make a profit.
FAQ
What insider transactions did CGEM’s Chief Scientific Officer report on September 8, 2026?
She exercised stock options for 4,000 shares of Cullinan Therapeutics common stock at $4.30 per share and sold 8,000 shares of common stock at a weighted average price of $21.57 per share in multiple trades.
Was the September 8, 2026 sale by CGEM’s insider made under a Rule 10b5-1 plan?
Yes. The filing states the share sale was effected pursuant to a Rule 10b5-1 trading plan that was established on August 7, 2025, indicating the sales were pre-arranged under that plan.
What stock option activity did the CGEM insider report?
She exercised stock options covering 4,000 shares of Cullinan Therapeutics common stock at an exercise price of $4.30 per share. After this exercise, 78,987 shares of common stock remained underlying her outstanding stock options from that award.
What is the vesting schedule disclosed for the exercised CGEM stock options?
The filing states that 25% of the shares under the option vested on July 4, 2020, and the remaining shares vested in 36 equal monthly installments after that date, reflecting a four-year vesting pattern for the option grant.
When do the reported CGEM stock options expire?
The stock options exercised for 4,000 shares of Cullinan Therapeutics common stock carry an expiration date of October 28, 2030, after which any unexercised portion of that option grant would cease to be exercisable.
AI-generated analysis. How Rhea-AI works. Not financial advice.
