Comparable stake leader
Soleus Capital Master Fund, L.P.
SEC ownership of C4 Therapeutics, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001662579.
Disclosed value leader
Sirenia Capital Management LP
Comparable rows
50/50
Latest evidence
30 Jun 2026
- Public ticker
- CCCC on Nasdaq
- Parsed ownership sources
-
13D/G, 13F, and 3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Soleus Capital Master Fund, L.P.
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Soleus Capital Master Fund, L.P.
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
30 Jun 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001662579
- Issuer location
- Watertown, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of C4 Therapeutics, 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
Soleus Capital Master Fun...
Disclosed value leader
Sirenia Capital Managemen...
Comparable rows
50/50
Latest evidence
30 Jun 2026
13D/G
13F
3/4/5
Lead comparable stake: 10%
13D/G row: Soleus Capital Master Fund, L.P.
Showing 1-8 of 50 holder rows.
Quick read
Soleus Capital Master Fund, L.P. leads the comparable SEC ownership view at 10%.
50 of 50 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 Soleus Capital Master Fund, L.P.'s linked filing trail.
Comparable ownership
Top 5
Soleus Capital Master Fund, L.P.
10%
Sirenia Capital Management LP
9.9%
RA CAPITAL MANAGEMENT, L.P.
9.9%
MORGAN STANLEY
9.3%
Lynx1 Capital Management LP
7.3%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Soleus Capital Master Fund, L.P. |
13D/G
|
10%
|
$19,791,153
10,361,860 shares
|
$0 | 31 Dec 2025 |
| Sirenia Capital Management LP |
13D/G
|
9.9%
|
$59,702,700
23,505,000 shares
|
$0 | 31 Mar 2026 |
| RA CAPITAL MANAGEMENT, L.P. |
13F
13D/G
Company
|
9.9%
from 13D/G
|
$21,040,000
8,000,000 shares
|
— | 31 Mar 2026 |
| MORGAN STANLEY |
13F
13D/G
Company
|
9.3%
from 13D/G
|
$23,860,411
9,072,400 shares
|
— | 31 Mar 2026 |
| Lynx1 Capital Management LP |
13F
13D/G
Company
|
7.3%
from 13D/G
|
$18,407,112
6,998,902 shares
|
— | 31 Mar 2026 |
| BlackRock, Inc. |
13D/G
13F
Company
|
6.9%
|
$35,860,491
7,678,906 shares
|
+$27,657,108 | 30 Jun 2026 |
| WASATCH ADVISORS LP |
13D/G
13F
Company
|
6.8%
|
$10,773,085
4,852,741 shares
|
-$5,817,712 | 30 Sep 2025 |
| Bain Capital Life Sciences Fund II, L.P. |
13D/G
BCLS II Equity Opportunities, LP
|
6.2%
|
$13,453,200
6,060,000 shares
|
$0 | 17 Oct 2025 |
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
Net insider flow leans to selling over the last 12 months. Net value: -$22,200.
Buys
$0
Insiders: 0
Sells
$22,200
Insiders: 1
Net
-$22,200
Shares: -10,000
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 10,000
| 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 | 10,000 | $0 | $22,200 | -$22,200 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 25 reporting-owner rows connected to C4 Therapeutics, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
25
Largest Forms 3/4/5 holder
Alain J. Cohen
Net 12M change
-$22,200
Latest report
10 Jul 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Alain J. Cohen | Director | $11,770,243 | Mixed | 04 Apr 2022 | ||
| Glenn Dubin | Director | $6,582,725 | Mixed | 01 Apr 2024 | ||
| Elena Prokupets | Director | $3,486,942 | Mixed | 27 Sep 2021 | ||
| Andrew Hirsch | President & CEO, Director | $2,031,625 | Mixed | 13 Feb 2026 | ||
| Leonard Reyno | Chief Medical Officer | $1,739,136 | -$22,200 | -1.3% | Median | 10 Jul 2026 |
| Kenneth Carl Anderson | Director | $1,385,452 | Mixed | 01 Jul 2026 | ||
| Stewart Fisher | Chief Scientific Officer | $921,946 | Mixed | 16 Sep 2024 | ||
| Kendra Adams | Chief Financial Officer | $727,835 | Mixed | 13 Feb 2026 | ||
| Paige Mahaney | Chief Scientific Officer | $636,759 | Mixed | 13 Feb 2026 | ||
| Kelly Schick | Chief People Officer | $566,775 | Mixed | 13 Feb 2026 | ||
| Scott N. Boyle | Chief Business Officer | $564,733 | Mixed | 13 Feb 2026 | ||
| Jolie M. Siegel | Chief Legal Officer | $406,666 | Mixed | 13 Feb 2025 | ||
| Lauren White | Chief Financial Officer | $318,053 | Mixed | 30 Aug 2023 | ||
| Adam Crystal | Chief Medical Officer | $250,282 | Mixed | 30 Jan 2023 | ||
| Donna Roy Grogan | Director | $196,863 | Mixed | 01 Jul 2026 | ||
| Mark Mossler | Chief Accounting Officer | $135,921 | Mixed | 13 Feb 2026 | ||
| Bruce Downey | Director | Mixed | 20 Jun 2024 | |||
| Utpal Koppikar | Director | Mixed | 24 Jun 2026 | |||
| Marc A. Cohen | Director | Mixed | 22 Jun 2022 | |||
| Laura Bessen | Director | Mixed | 24 Jun 2026 |
Recent insider transactions for C4 Therapeutics, 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Leonard Reyno | CCCC | Common Stock | Tax liability | -1.95% | -7,397 | 372,406 | 10 Jul 2026 | Direct | ||
| Leonard Reyno | CCCC | Common Stock | Options Exercise | 4.2% | 15,325 | 379,803 | 10 Jul 2026 | Direct | ||
| Kenneth Carl Anderson | CCCC | Common Stock | Award | 3.82% | 2,650 | 71,950 | 01 Jul 2026 | Direct | ||
| Donna Roy Grogan | CCCC | Common Stock | Award | 4.67% | 3,341 | 74,853 | 01 Jul 2026 | Direct | ||
| Owen Hughes | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Steven L. Hoerter | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Utpal Koppikar | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Kenneth Carl Anderson | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Ronald Harold Wilfred Cooper | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Laura Bessen | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Stephen Fawell | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Donna Roy Grogan | CCCC | Stock Option (Right to Buy) | Award | 62,000 | 62,000 | 24 Jun 2026 | Direct | |||
| Kenneth Carl Anderson | CCCC | Common Stock | Options Exercise | 1.57% | 1,070 | 69,300 | 01 Jun 2026 | Direct | ||
| Kenneth Carl Anderson | CCCC | Stock Option (Right to Buy) | Options Exercise | -100% | -1,070 | 0 | 01 Jun 2026 | Direct | ||
| Kenneth Carl Anderson | CCCC | Common Stock | Award | 6.66% | 4,259 | 68,230 | 01 Apr 2026 | Direct | ||
| Donna Roy Grogan | CCCC | Common Stock | Award | 8.12% | 5,370 | 71,512 | 01 Apr 2026 | Direct | ||
| Andrew Hirsch | CCCC | Common Stock | Tax liability | -0.84% | -9,057 | 1,074,934 | 15 Feb 2026 | Direct | ||
| Andrew Hirsch | CCCC | Common Stock | Options Exercise | 1.92% | 20,400 | 1,083,991 | 15 Feb 2026 | Direct | ||
| Scott N. Boyle | CCCC | Common Stock | Tax liability | -2.37% | -7,269 | 298,801 | 14 Feb 2026 | Direct | ||
| Scott N. Boyle | CCCC | Common Stock | Options Exercise | 7.35% | 20,950 | 306,070 | 14 Feb 2026 | Direct | ||
| Paige Mahaney | CCCC | Common Stock | Tax liability | -0.72% | -2,446 | 336,910 | 14 Feb 2026 | Direct | ||
| Paige Mahaney | CCCC | Common Stock | Options Exercise | 2.12% | 7,050 | 339,356 | 14 Feb 2026 | Direct | ||
| Kelly Schick | CCCC | Common Stock | Tax liability | -2.37% | -7,269 | 299,881 | 14 Feb 2026 | Direct | ||
| Kelly Schick | CCCC | Common Stock | Options Exercise | 7.32% | 20,950 | 307,150 | 14 Feb 2026 | Direct | ||
| Andrew Hirsch | CCCC | Common Stock | Tax liability | -3.49% | -39,154 | 1,083,991 | 14 Feb 2026 | Direct | ||
| Andrew Hirsch | CCCC | Common Stock | Options Exercise | 7.85% | 81,725 | 1,123,145 | 14 Feb 2026 | Direct | ||
| Leonard Reyno | CCCC | Common Stock | Tax liability | -4.18% | -16,579 | 379,803 | 14 Feb 2026 | Direct | ||
| Leonard Reyno | CCCC | Common Stock | Options Exercise | 8.47% | 30,950 | 396,382 | 14 Feb 2026 | Direct | ||
| Kendra Adams | CCCC | Common Stock | Tax liability | -3.84% | -15,381 | 385,098 | 14 Feb 2026 | Direct | ||
| Kendra Adams | CCCC | Common Stock | Options Exercise | 8.38% | 30,950 | 400,479 | 14 Feb 2026 | Direct | ||
| Mark Mossler | CCCC | Common Stock | Tax liability | -4.35% | -3,268 | 71,916 | 14 Feb 2026 | Direct | ||
| Mark Mossler | CCCC | Common Stock | Options Exercise | 14.3% | 9,420 | 75,184 | 14 Feb 2026 | Direct | ||
| Scott N. Boyle | CCCC | Common Stock | Tax liability | -0.56% | -1,735 | 306,070 | 13 Feb 2026 | Direct | ||
| Scott N. Boyle | CCCC | Common Stock | Options Exercise | 1.65% | 5,000 | 307,805 | 13 Feb 2026 | Direct | ||
| Scott N. Boyle | CCCC | Common Stock | Award | 185.5% | 200,000 | 307,805 | 13 Feb 2026 | Direct | ||
| Paige Mahaney | CCCC | Common Stock | Award | 241.6% | 240,000 | 339,356 | 13 Feb 2026 | Direct | ||
| Kelly Schick | CCCC | Common Stock | Tax liability | -0.56% | -1,735 | 307,150 | 13 Feb 2026 | Direct | ||
| Kelly Schick | CCCC | Common Stock | Options Exercise | 1.65% | 5,000 | 308,885 | 13 Feb 2026 | Direct | ||
| Kelly Schick | CCCC | Common Stock | Award | 183.7% | 200,000 | 308,885 | 13 Feb 2026 | Direct | ||
| Andrew Hirsch | CCCC | Common Stock | Award | 165.4% | 700,000 | 1,123,145 | 13 Feb 2026 | Direct | ||
| Leonard Reyno | CCCC | Common Stock | Award | 153.5% | 240,000 | 396,382 | 13 Feb 2026 | Direct | ||
| Kendra Adams | CCCC | Common Stock | Tax liability | -0.46% | -1,863 | 400,479 | 13 Feb 2026 | Direct | ||
| Kendra Adams | CCCC | Common Stock | Options Exercise | 0.94% | 3,750 | 402,342 | 13 Feb 2026 | Direct | ||
| Kendra Adams | CCCC | Common Stock | Award | 147.8% | 240,000 | 402,342 | 13 Feb 2026 | Direct | ||
| Mark Mossler | CCCC | Common Stock | Award | 313% | 56,980 | 75,184 | 13 Feb 2026 | Direct | ||
| Leonard Reyno | CCCC | Common Stock | Sale | -6.01% | $22,200 | $2.22 | -10,000 | 156,382 | 16 Jan 2026 | Direct |
| Kenneth Carl Anderson | CCCC | Common Stock | Award | 4.24% | 5,958 | 146,532 | 02 Jan 2026 | Direct | ||
| Donna Roy Grogan | CCCC | Common Stock | Award | 12.8% | 7,513 | 66,142 | 02 Jan 2026 | Direct | ||
| Paige Mahaney | CCCC | Common Stock | Tax liability | -5.38% | -5,644 | 99,356 | 28 Oct 2025 | Direct | ||
| Paige Mahaney | CCCC | Common Stock | Options Exercise | 22.4% | 19,200 | 105,000 | 28 Oct 2025 | Direct |
* marks a reported price that did not pass the local price check.