KRRO Korro Bio, Inc.

NASDAQ
$13.81

Korro Bio, Inc. (KRRO) Insider Activity

What the officers, directors and large holders did with their own shares. Only open-market purchases and sales count toward the totals — grants, option exercises and shares withheld for tax are compensation mechanics, not decisions, and they're listed separately below.

30D 90D 6M 1Y
Insider signal Bullish Insiders bought more than they sold over this window — uncommon at any size.
Cluster activity 0 buyers in the last 30 days 1 buyer in the last 90 days 6 sellers in the last 90 days
Insiders buying
9
12 transactions
Insiders selling
6
28 transactions
Purchases
$20.8M
1,871,104 shares
Sales
$5.0M
360,084 shares
Net activity
$15.8M
purchases less sales

How much of that selling was preplanned? 91% planned / 9% discretionary

10b5-1 plan sales $4.6M 22 transactions · 322,552 shares
Discretionary sales $439.1K 6 transactions · 37,532 shares

Largest single sale: $1.4M.

Where they traded

Buy Sell Dot area is proportional to transaction value.

Last open-market purchase: August 10, 2026 .

Recent open-market activity

Date Insider Role Action Shares Price Value Held after
Dolan Oliver Senior Vice President, Finance Sell 10b5-1 6 $13.60 $82 16,246 −0% of holding
Dolan Oliver Senior Vice President, Finance Sell 10b5-1 7,347 $13.51 $99.3K 16,252 −31.1% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 300 $13.96 $4.2K 680,948 −0% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 28,468 $14.00 $398.6K 681,197 −4% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 2,143 $13.96 $29.9K 704,781 −0.3% of holding
Buy 1,462 $13.19 $19.3K 1,544,980
Buy 5,222 $11.40 $59.5K 1,543,518
Aiyar Ram President and CEO Sell 5,802 $10.84 $62.9K 69,046 −7.8% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 9,323 $13.96 $130.1K 706,556 −1.3% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 100,700 $14.03 $1.4M 707,373 −12.5% of holding
FORMELA JEAN FRANCOIS 4 fills Director Sell 10b5-1 48,438 $14.61 $707.5K 793,994 −5.7% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 119,005 $14.25 $1.7M 834,673 −12.5% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 3,962 $13.95 $55.3K 936,252 −0.4% of holding
Cerio Jeffrey General Counsel Sell 6,609 $10.83 $71.6K 35,293 −15.8% of holding
Vincent Loic A Chief Scientific Officer Sell 3,418 $10.83 $37.0K 18,297 −15.7% of holding
Dolan Oliver Senior Vice President, Finance Sell 3,383 $10.83 $36.6K 18,099 −15.7% of holding
Chappell Todd Chief Operating Officer Sell 3,168 $10.83 $34.3K 16,964 −15.7% of holding
Aiyar Ram President and CEO Sell 15,152 $12.98 $196.7K 74,848 −16.8% of holding
FORMELA JEAN FRANCOIS 2 fills Director Sell 10b5-1 2,860 $13.95 $39.9K 939,634 −0.3% of holding
Buy 520 $10.60 $5.5K 1,538,296
Buy 207,100 $11.11 $2.3M 1,297,893
SANDELL SCOTT D 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
BASKETT FOREST 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Mathers Edward T 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Walker Paul Edward 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Florence Anthony A. Jr. 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Makhzoumi Mohamad 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Chang Carmen 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893
Yang Rick 10% Owner Buy 207,100 $11.11 $2.3M 1,297,893

Form 4s are due within two business days of a transaction, so this is close to real time — unlike the quarterly 13F data on the Institutional tab. A single large sale often reflects a prearranged 10b5-1 plan rather than a fresh view, so read a pattern of sales rather than any one of them.