Holder evidence
37
SEC ownership of Cyclerion Therapeutics, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001755237.
Lead holder
Peter M. Hecht
13D/G signal
Peter M. Hecht
Latest evidence
31 Mar 2026
- CIK
- 0001755237
- Symbol
- CYCN on Nasdaq
- Location
- Cambridge, MA
- SEC evidence mix
- 13D/G, 3/4/5, and 13F
- Lead holder
- Peter M. Hecht
- Latest large-stake holder
- Peter M. Hecht
- Latest evidence date
- 31 Mar 2026
Issuer identity
Ownership snapshot
Ownership snapshot
Top shareholders of Cyclerion 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.
Lead holder
Peter M. Hecht
13D/G signal
Peter M. Hecht
Evidence rows
37
Latest as of
31 Mar 2026
13D/G
3/4/5
13F
Lead comparable stake: 28%
13D/G row: Peter M. Hecht
Showing first 8 of 37 holder rows.
Open remaining rows
Rank 1 holder
Peter M. Hecht
13D/G
3/4/5
- Ownership
- 28%
- Position
- $3.8M
Rank 2 holder
FMR LLC
13F
13D/G
- Ownership
- 15%
- Position
- $7.3K
Rank 3 holder
J. WOOD CAPITAL ADVISORS LLC
13D/G
- Ownership
- 5.4%
- Position
- $496.4K
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Peter M. Hecht |
13D/G
3/4/5
Director, 10%+ Owner
|
28%
|
$3,803,918
1,028,086 shares
|
$0 | 25 Mar 2025 |
| FMR LLC |
13F
13D/G
Company
|
15%
from 13D/G
|
$7,276
4,740 shares
|
— | 31 Mar 2026 |
| J. WOOD CAPITAL ADVISORS LLC |
13D/G
|
5.4%
|
$496,363
181,818 shares
|
$0 | 25 Mar 2025 |
| American Endowment Foundation |
13D/G
|
4.9%
|
$492,196
133,026 shares
|
$0 | 31 Dec 2024 |
| TYNDALL CAPITAL PARTNERS L P |
13D/G
|
4.8%
|
$487,287
155,187 shares
|
-$30,113 | 30 Jun 2025 |
| GEODE CAPITAL MANAGEMENT, LLC |
13F
Company
|
2.5%
|
$129,800
84,550 shares
|
— | 31 Mar 2026 |
| CITADEL ADVISORS LLC |
13F
Company
|
0.54%
|
$28,031
18,261 shares
|
— | 31 Mar 2026 |
| BlackRock, Inc. |
13F
Company
|
0.5%
|
$26,035
16,797 shares
|
— | 31 Mar 2026 |
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 30 May 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
Current reporting-owner rows connected to Cyclerion Therapeutics, Inc.. Open the relationship link for the CIK-to-CIK filing trail.
Rows
18
Lead holder
Peter M. Hecht
Net 12M change
$0
Latest report
07 Aug 2025
Recent insider transactions for Cyclerion Therapeutics, Inc.
Showing up to 300 most recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | Reported value | Reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Rhonda M. Chicko | CYCN | Stock Option (Right to Buy) | Award | 25,000 | 25,000 | 07 Aug 2025 | Direct |
* indicates a reported price that failed the local validity check.