Form 4 for CRBU Caribou Biosciences, Inc.
Accepted 2026-02-24 00:00:00 ET · period of report 2026-02-20 · accession 0001891113-26-000002 · SEC index · Original document
Summary rows
Aggregated the way they appear in lists: one row per insider, transaction code and security table.
| X | Filed | Traded | Ticker | Insider | Title | Type | Price | Qty | Owned | ΔOwn | Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| D | 2026-02-24 | 2026-02-24 | CRBU | Khan Ruhi Ahmad | Chief Business Off | S - Sale | $1.96 | -6,938 | 105.0K | -6% | -$13.6K |
| D | 2026-02-24 | 2026-02-20 | CRBU | Khan Ruhi Ahmad | Chief Business Off | A - Grant | $0.00 | +45.0K | 111.9K | +67% | $0 |
| D | 2026-02-24 | 2026-02-20 | CRBU | Khan Ruhi Ahmad | Chief Business Off | A - Grant | $0.00 | +202.5K | 202.5K | New | $0 |
Purchase Sale Sale after option exercise All abbreviations
Every reported transaction
| # | Table | Security | Date | Code | A/D | Shares | Price | Owned after | Own | Exercise / expiry | Underlying | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Common | Common Stock | 2026-02-24 | S | D | 6,938 | $1.96 | 104,998 | D | — | — | (F2) Reflects the number of shares of common stock that were sold in a "sell-to-cover" transaction for the sole purpose of satisfying tax withholding obligations in connection with the vesting of RSUs previously granted to the reporting person and does not represent a discretionary trade by the reporting person. This transaction was made pursuant to a Rule 10b5-1 trading plan in the form of a durable sell-to-cover instruction adopted prior to the 2023 amendments to Rule 10b5-1. The trading plan provides for the automatic sale of shares of common stock necessary to satisfy the reporting person's tax withholding obligations incurred in connection with the vesting of RSUs. |
| 2 | Common | Common Stock | 2026-02-20 | A | A | 45,000 | $0.00 | 111,936 | D | — | — | (F1) This reflects restricted stock units ("RSUs") that vest in four equal annual installments beginning on February 20, 2027, subject to the reporting person continuing to provide service to the Issuer through the applicable vesting dates. The RSUs will be settled in stock within 30 days after each vesting date. |
| 3 | Derivative | Option to purchase Common Stock | 2026-02-20 | A | A | 202,500 | $0.00 | 202,500 | D | $1.80 · — to 2036-02-19 | 202,500 Common Stock | (F3) 1/48 of the total number of shares subject to this option will vest on each monthly anniversary of the grant date such that the option will be fully vested on February 20, 2030, subject to the reporting person continuing to provide service to the Issuer through each such vesting date. |