Comparable stake leader
Barbara Kosacz
SEC ownership of Kronos Bio, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001741830.
Disclosed value leader
Barbara Kosacz
Comparable rows
0/9
Latest evidence
15 Oct 2024
- Parsed ownership sources
- 3/4/5
- Largest SEC-reported holder
- Barbara Kosacz
- Latest parsed ownership date
- 15 Oct 2024
- Issuer CIK
- 0001741830
- Issuer location
- San Mateo, CA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
1 signal
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Kronos Bio, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Barbara Kosacz
Disclosed value leader
Barbara Kosacz
Comparable rows
0/9
Latest evidence
15 Oct 2024
3/4/5
Highest disclosed value: $1,099,524
9 rows are not safely comparable across share classes.
Showing 1-8 of 9 holder rows.
Quick read
Barbara Kosacz has the largest disclosed position value at $1.1M.
0 of 9 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Barbara Kosacz's linked filing trail.
Disclosed position value
Top 5
Barbara Kosacz
$1.1M
B. al Wakeel
$409.6K
Jorge DiMartino
$373.1K
Christopher Dinsmore
$308.9K
Charles Y. Lin
$247.2K
Value bars compare disclosed positions; verify each figure against the linked filing evidence.
Detailed SEC evidence table Showing 1-8 of 9 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Barbara Kosacz |
3/4/5
COO & General Counsel
|
—
mixed-class rows
|
$1,099,524
1,137,333 shares
mixed-class rows
|
— | 04 Jan 2024 |
| B. al Wakeel |
3/4/5
Chief Financial Officer
|
—
class O/S missing
|
$409,646
346,102 shares
|
— | 06 Jul 2023 |
| Jorge DiMartino |
3/4/5
Chief Medical Officer & VP
|
—
class O/S missing
|
$373,125
315,246 shares
|
— | 04 Jan 2024 |
| Christopher Dinsmore |
3/4/5
Chief Scientific Officer
|
—
class O/S missing
|
$308,883
260,969 shares
|
— | 04 Jan 2024 |
| Charles Y. Lin |
3/4/5
Chief Scientific Officer
|
—
mixed-class rows
|
$247,248
307,503 shares
mixed-class rows
|
— | 15 Oct 2024 |
| Allison Frisbee |
3/4/5
Chief Administrative Officer
|
—
mixed-class rows
|
$215,533
277,410 shares
mixed-class rows
|
— | 15 Oct 2024 |
| Elizabeth A. Olek |
3/4/5
SR VP, CLINICAL SCIENCE
|
—
class O/S missing
|
$203,693
193,275 shares
|
— | 21 Feb 2024 |
| Marianne de Backer |
3/4/5
Director
|
—
class O/S missing
|
—
34,000 shares
|
— | 22 Jun 2023 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Insider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 12 Jun 2025.
Buys
$0
Insiders: 0
Sells
$0
Insiders: 0
Net
$0
Shares: 0
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 0
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 0 | $0 | $0 | $0 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 20 reporting-owner rows connected to Kronos Bio, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
20
Largest Forms 3/4/5 holder
Barbara Kosacz
Net 12M change
$0
Latest report
20 Jun 2025
Recent insider transactions for Kronos Bio, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Arie Belldegrun | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -679,575 | 0 | 20 Jun 2025 | By Bellco Legacy II Trust | ||
| Arie Belldegrun | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -2,765,314 | 0 | 20 Jun 2025 | By Vida Ventures, LLC | ||
| Arie Belldegrun | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -122,600 | 0 | 20 Jun 2025 | Direct | ||
| Norbert W. Bischofberger | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -11,857,138 | 0 | 20 Jun 2025 | See Footnote | ||
| Norbert W. Bischofberger | KRON | Employee Stock Option (Right to Buy) | Disposed to Issuer | -100% | -1,967,854 | 0 | 20 Jun 2025 | Direct | ||
| Elena Ridloff | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -25,296 | 0 | 20 Jun 2025 | Direct | ||
| Elena Ridloff | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -136,200 | 0 | 20 Jun 2025 | Direct | ||
| David M. Tanen | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -26,375 | 0 | 20 Jun 2025 | By Daughter | ||
| David M. Tanen | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -52,750 | 0 | 20 Jun 2025 | By Son | ||
| David M. Tanen | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -471,230 | 0 | 20 Jun 2025 | See Footnote | ||
| David M. Tanen | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -363,428 | 0 | 20 Jun 2025 | Direct | ||
| David M. Tanen | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -228,100 | 0 | 20 Jun 2025 | Direct | ||
| Roshawn A. Blunt | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -143,200 | 0 | 20 Jun 2025 | Direct | ||
| Taiyin Yang | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -11,333 | 0 | 20 Jun 2025 | Direct | ||
| Taiyin Yang | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -131,350 | 0 | 20 Jun 2025 | Direct | ||
| Joshua A. Kazam | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -94,481 | 0 | 20 Jun 2025 | Direct | ||
| Joshua A. Kazam | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -122,600 | 0 | 20 Jun 2025 | Direct | ||
| Katherine V Stultz | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -109,079 | 0 | 20 Jun 2025 | Direct | ||
| Roger D. Dansey | KRON | Stock Option (Right to Buy) | Disposed to Issuer | -100% | -107,868 | 0 | 20 Jun 2025 | Direct | ||
| Deborah Knobelman | KRON | Common Stock | Disposition pursuant to a tender of shares in a change of control transaction | -100% | -139,422 | 0 | 20 Jun 2025 | Direct | ||
| Deborah Knobelman | KRON | Employee Stock Option (Right to Buy) | Disposed to Issuer | -100% | -246,390 | 0 | 20 Jun 2025 | Direct |
* marks a reported price that did not pass the local price check.