Cyclerion Therapeutics, Inc.
Total Trades
2
Buys
0
Sells
2
Largest Trade
$500K+
Insiders
2
Institutional Funds
12
Inst. Value
$100K–$500K
Activist Filings
22
Insider Trades
| Insider | Title | Type | Value | Shares | Price | Date |
|---|---|---|---|---|---|---|
| Slate Path Capital LP | 10% Owner | SELL | $500K+ | 358K | $1.55 | Nov 25, 2024 |
| MCGUIRE TERRANCE | Director | SELL | <$1K | 8 | $3.40 | Aug 11, 2023 |
Institutional Ownership
13F filings as of Dec 31, 2025 · 12 funds holding
| Fund | Shares | Value | Type |
|---|---|---|---|
| Siren, L.L.C. | 116K | $100K–$500K | SH |
| GEODE CAPITAL MANAGEMENT, LLC | 42K | $50K–$100K | SH |
| BlackRock, Inc. | 17K | $15K–$50K | SH |
| VANGUARD GROUP INC | 16K | $15K–$50K | SH |
| CITIGROUP INC | 8K | $1K–$15K | SH |
| UBS Group AG | 376 | <$1K | SH |
| GROUP ONE TRADING LLC | 192 | <$1K | SH |
| Activest Wealth Management | 100 | <$1K | SH |
| MAI Capital Management | 100 | <$1K | SH |
| WHI TRUST Co LLC | 72 | <$1K | SH |
| BNP PARIBAS FINANCIAL MARKETS | 5 | <$1K | SH |
| MORGAN STANLEY | 1 | <$1K | SH |
Activist & 5%+ Owners
SC 13D/13G filings — investors holding 5%+ of outstanding shares
SC 13G · Oct 17, 2025
5.4%
182K shares
Tyndall Capital Partners, L.P.
SC 13G/A · Aug 14, 2025
4.8%
155K shares
Tyndall Capital Partners, L.P.
SC 13G/A · May 15, 2025
5.1%
165K shares
SC 13D/A · Mar 29, 2025
27.9%
1.0M shares
SC 13G/A · Feb 12, 2025
0.0%
0 shares
SC 13G/A · Feb 12, 2025
4.9%
133K shares
SC 13G/A · Feb 12, 2025
0.2%
5K shares
SC 13G/A · Dec 6, 2024
0.0%
0 shares
SC 13G/A · Jul 12, 2024
4.3%
11.6M shares
Tyndall Capital Partners, L.P.
SC 13G/A · Feb 14, 2024
6.7%
164K shares
SC 13G/A · Feb 9, 2024
5.7%
13.8M shares
SC 13G/A · Jan 22, 2024
14.6%
358K shares
SC 13D/A · Dec 5, 2023
26.9%
841K shares
SC 13G · Sep 5, 2023
5.0%
122K shares
SC 13D/A · May 23, 2023
20.0%
518K shares
SC 13D/A · May 12, 2023
20.0%
10.4M shares
SC 13D/A · Apr 3, 2023
9.2%
4.2M shares
SC 13G · Jan 13, 2023
16.5%
7.2M shares
SC 13D/A · Nov 21, 2022
9.2%
4.2M shares
SC 13D · Oct 21, 2022
16.5%
7.2M shares
SC 13G/A · Feb 11, 2022
16.5%
7.2M shares
SC 13G/A · Feb 11, 2022
6.4%
2.8M shares