[Form 4] Upstream Bio, Inc. Insider Trading Activity
Filing Impact
Filing Sentiment
Form Type
4
Rhea-AI Filing Summary
Upstream Bio, Inc. reported that Chief Medical Officer Aaron Deykin sold 895 shares of common stock at $6.10 per share on June 16, 2026. According to the company’s sell-to-cover policy, these shares were sold automatically to cover tax withholding on vested restricted stock units and were not sold at his discretion.
After this transaction, Deykin directly holds 33,197 shares of Upstream Bio common stock, which includes 1,405 shares previously acquired under the company’s 2024 Employee Stock Purchase Plan.
Positive
- None.
Negative
- None.
Insider Trade Summary
Net Seller: 895 shares ($5,460)
Net Sell
1 txn
Insider
Deykin Aaron
Role
Chief Medical Officer
Sold
895 shs ($5K)
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 895 | $6.10 | $5K |
Holdings After Transaction:
Common Stock — 33,197 shares (Direct, null)
Footnotes (1)
- The Issuer has adopted a "sell-to-cover" policy to satisfy the tax withholding obligations of the Reporting Person. The sales reported on this Form 4 represent the number of shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. Such sales were automatic and not at the discretion of the Reporting Person. Includes 1,405 shares of Common Stock previously acquired under the Issuer's 2024 Employee Stock Purchase Plan.
Key Figures
Shares sold: 895 shares
Sale price: $6.10 per share
Shares held after transaction: 33,197 shares
+1 more
4 metrics
Shares sold
895 shares
Common stock sold on June 16, 2026
Sale price
$6.10 per share
Open-market sale price for common stock
Shares held after transaction
33,197 shares
Direct holdings following the sale
ESPP shares included
1,405 shares
Previously acquired under 2024 Employee Stock Purchase Plan
Key Terms
sell-to-cover, restricted stock units, Employee Stock Purchase Plan, open-market sale
4 terms
sell-to-cover financial
"The Issuer has adopted a "sell-to-cover" policy to satisfy the tax withholding obligations..."
Sell-to-cover is when part of newly issued or exercised company stock is immediately sold to pay required taxes and fees, so the recipient keeps the remaining shares. For investors this matters because it reduces the number of shares insiders or employees actually hold after a grant, can create small, routine share sales that aren’t signal of cashing out, and slightly increases share supply on the market—like selling a portion of a paycheck to cover the tax bill.
restricted stock units financial
"to cover tax withholding obligations in connection with the vesting of restricted stock units."
Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.
Employee Stock Purchase Plan financial
"Includes 1,405 shares of Common Stock previously acquired under the Issuer's 2024 Employee Stock Purchase Plan."
An employee stock purchase plan is a company program that lets workers buy shares through small payroll deductions, often at a discount to the market price and after a set offering period. Think of it like a workplace savings plan that turns into ownership: it encourages employees to share in the company’s success and can create predictable buying or selling of stock that investors watch because it affects supply, demand and employee incentives.
open-market sale financial
"transaction_action": "open-market sale""
An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.
