Comparable stake leader
BML Investment Partners, L.P.
SEC ownership of Third Harmonic Bio, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001923840.
Disclosed value leader
Atlas Venture Fund XI, L.P.
Comparable rows
5/21
Latest evidence
31 Mar 2026
- Parsed ownership sources
- 13D/G, 13F, and 3/4/5
- Largest SEC-reported holder
- BML Investment Partners, L.P.
- Latest 13D/G holder
- BML Investment Partners, L.P.
- Latest parsed ownership date
- 31 Mar 2026
- Issuer CIK
- 0001923840
- Issuer location
- San Francisco, CA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Third Harmonic 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
BML Investment Partners, ...
Disclosed value leader
Atlas Venture Fund XI, L.P.
Comparable rows
5/21
Latest evidence
31 Mar 2026
13D/G
13F
3/4/5
Lead comparable stake: 8.2%
16 rows are not safely comparable across share classes.
13D/G row: BML Investment Partners, L.P.
Showing 1-8 of 21 holder rows.
Quick read
BML Investment Partners, L.P. leads the comparable SEC ownership view at 8.2%.
5 of 21 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 BML Investment Partners, L.P.'s linked filing trail.
Comparable ownership
Top 5
BML Investment Partners, L.P.
8.2%
FMR LLC
0%
RHUMBLINE ADVISERS
0.04%
GAMMA Investing LLC
0%
SBI Securities Co., Ltd.
0%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 21 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| BML Investment Partners, L.P. |
13D/G
|
8.2%
|
$19,179,460
3,724,167 shares
|
$0 | 11 Feb 2025 |
| FMR LLC |
13D/G
|
0%
|
$5,490
1,066 shares
|
-$13,057,691 | 31 Mar 2025 |
| RHUMBLINE ADVISERS |
13F
Company
|
0.04%
|
$107,488
19,980 shares
|
— | 31 Mar 2026 |
| GAMMA Investing LLC |
13F
Company
|
0%
|
$2,464
458 shares
|
— | 31 Mar 2026 |
| SBI Securities Co., Ltd. |
13F
Company
|
0%
|
$1
20 shares
|
— | 31 Mar 2026 |
| Atlas Venture Fund XI, L.P. |
3/4/5
10%+ Owner
|
—
class O/S missing
|
$140,112,473
9,798,075 shares
|
— | 01 Nov 2024 |
| ORBIMED ADVISORS LLC |
3/4/5
Director, 10%+ Owner
|
—
class O/S missing
|
$59,522,120
5,779,071 shares
|
— | 19 Sep 2022 |
| BVF PARTNERS L P/IL |
3/4/5
Other*
|
—
class O/S missing
|
$2,526,696
176,692 shares
|
— | 29 Oct 2024 |
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 06 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 Third Harmonic Bio, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
20
Largest Forms 3/4/5 holder
Atlas Venture Fund XI, L.P.
Net 12M change
$0
Latest report
11 Aug 2025
Recent insider transactions for Third Harmonic 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Natalie C. Holles | THRD | Common Stock | Other | -100% | -1,218,836 | 0 | 11 Aug 2025 | Direct | ||
| Natalie C. Holles | THRD | Restricted Stock Unit | Other | -100% | -50,000 | 0 | 11 Aug 2025 | Direct | ||
| Natalie C. Holles | THRD | Stock Option | Other | -100% | -998,854 | 0 | 11 Aug 2025 | Direct | ||
| Michael Gladstone | THRD | Stock Option | Other | -100% | -43,584 | 0 | 11 Aug 2025 | Direct | ||
| Christopher M. Murphy | THRD | Restricted Stock Unit | Other | -100% | -47,500 | 0 | 11 Aug 2025 | Direct | ||
| Iwicki Mark T. | THRD | Common Stock | Other | -100% | -128,631 | 0 | 11 Aug 2025 | Direct | ||
| Iwicki Mark T. | THRD | Stock Option | Other | -100% | -83,296 | 0 | 11 Aug 2025 | Direct | ||
| Hans Martin Seidel | THRD | Common Stock | Other | -100% | -85,753 | 0 | 11 Aug 2025 | Direct | ||
| Hans Martin Seidel | THRD | Stock Option | Other | -100% | -53,090 | 0 | 11 Aug 2025 | Direct | ||
| Thomas P. Soloway | THRD | Stock Option | Other | -100% | -120,166 | 0 | 11 Aug 2025 | Direct | ||
| David P. Bonita | THRD | Common Stock | Other | -100% | -5,779,071 | 0 | 11 Aug 2025 | Direct | ||
| David P. Bonita | THRD | Stock Option | Other | -100% | -43,584 | 0 | 11 Aug 2025 | Direct |
* marks a reported price that did not pass the local price check.