SYNLOGIC INC SYBX
COM NEW · Common Stock · CUSIP 87166L209
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersWinchester, MA
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable. Shares outstanding: 9.2m as of 2023-11-02, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $2.74. Options: 1 managers hold calls ($0 notional), 1 hold puts ($0).
Biggest buyers
| FMR LLC | New | +646.8k |
| ARMISTICE CAPITAL, LLC | New | +599.9k |
| ORBIMED ADVISORS LLC | New | +402.0k |
| NEA Management Company, LLC | New | +281.9k |
| Atlas Venture Associates IX, LLC | New | +176.8k |
| Alyeska Investment Group, L.P. | New | +168.0k |
| VANGUARD GROUP INC | New | +149.6k |
| Sofinnova Investments, Inc. | New | +38.3k |
| GEODE CAPITAL MANAGEMENT, LLC | New | +30.3k |
| Fiduciary Trust Co | New | +22.4k |
Biggest sellers
| None |
Biggest calls
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | New | $00 shares |
Biggest puts
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | New | $00 shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
Funicular Funds, LP
13D · may seek influence
no change · filed 2026-07-29
Stated purposeItem 4 is hereby amended to add the following: On July 28, 2026, the Issuer entered into an Agreement and Plan of Merger (the "Merger Agreement") by and among the Issuer, Caldera Therapeutics, Inc., a Delaware corporation ("Caldera"), Sonic Holdco, Inc., a Delaware corporation ("Parent"), Yellowstone Merger Sub, Inc., a Delaware corporation and a direct, wholly owned subsidiary of Parent ("Caldera Merger Sub"), and Sonic Merger Sub, Inc., a Delaware corporation and a direct, wholly owned subsidiary of Parent ("Synlogic Merger Sub"). Pursuant to and subject to the terms of the Merger Agreement, among other things, the Issuer will be merged with and into Synlogic Merger Sub, with the Issuer surviving as a wholly owned subsidiary of Parent (the "Merger"), as more fully described in the Form … Full filing |
28.3% |
New Enterprise Associates 14, L.P.
13D · may seek influence
filed 2026-07-29
Stated purposeAs previously disclosed by the Issuer, on July 28, 2026, the Issuer entered into an Agreement and Plan of Merger (the "Merger Agreement") by and among the Issuer, Caldera Therapeutics, Inc. ("Caldera"), Sonic Holdco, Inc. ("Parent"), Yellowstone Merger Sub, Inc., a direct, wholly owned subsidiary of Parent ("Caldera Merger Sub"), and Sonic Merger Sub, Inc., a direct, wholly owned subsidiary of Parent ("Synlogic Merger Sub"). Pursuant to the Merger Agreement, and upon the terms and subject to the satisfaction of the conditions described therein, the Issuer will be merged with and into Synlogic Merger Sub, with the Issuer surviving as a wholly owned subsidiary of Parent (the "Synlogic Merger"), and Caldera will be merged with and into Caldera Merger Sub, with Caldera surviving as a wholly o… Full filing |
25.0% |
| Baselake Partners, LP 13G · passive investor new · filed 2026-01-23 | 9.7% |
Insider purchases and sales in Q3 2023
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2021 | 0 | — | 0 | — | — |
| Q1 2022 | 0 | — | 0 | — | — |
| Q2 2022 | 1 | $10.6k | 2 | $28.3k | — |
| Q3 2022 | 0 | — | 0 | — | — |
| Q4 2022 | 0 | — | 0 | — | — |
| Q1 2023 | 0 | — | 0 | — | — |
| Q2 2023 | 0 | — | 3 | — | — |
| Q3 2023 | 0 | — | 0 | — | — |
None reported in Q3 2023.
Holders, Q3 2023
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.00% of their portfolio | 646.8k $1.8m | New |
| ARMISTICE CAPITAL, LLC 0.05% of their portfolio | 599.9k $1.7m | New |
| ORBIMED ADVISORS LLC 0.02% of their portfolio | 402.0k $1.1m | New |
| NEA Management Company, LLC 0.05% of their portfolio | 281.9k $614.6k | New |
| Atlas Venture Associates IX, LLC 4.23% of their portfolio | 176.8k $496.8k | New |
| Alyeska Investment Group, L.P. 0.00% of their portfolio | 168.0k $472.2k | New |
| VANGUARD GROUP INC 0.00% of their portfolio | 149.6k $420.3k | New |
| OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AMERICAS (LLC) 0.00% of their portfolio | 40.5k $113.9k | Not comparable |
| Sofinnova Investments, Inc. 0.01% of their portfolio | 38.3k $107.7k | New |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 30.3k $85.2k | New |
| Fiduciary Trust Co 0.00% of their portfolio | 22.4k $62.8k | New |
| HARBOR CAPITAL ADVISORS, INC. 0.01% of their portfolio | 21.4k $60.1k | New |
| Ikarian Capital, LLC 0.02% of their portfolio | 20.4k $57.5k | New |
| BlackRock Inc. 0.00% of their portfolio | 20.0k $56.2k | New |
| WINTON GROUP Ltd 0.00% of their portfolio | 12.4k $34.8k | New |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 11.0k $30.9k | New |
| STATE STREET CORP 0.00% of their portfolio | 10.3k $28.9k | New |
| OSAIC HOLDINGS, INC. 0.00% of their portfolio | 3.2k $9.1k | New |
| Ensign Peak Advisors, Inc 0.00% of their portfolio | 2.2k $6.2k | New |
| MORGAN STANLEY 0.00% of their portfolio | 1.6k $4.6k | New |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 897 $3.0k | New |
| Tower Research Capital LLC (TRC) 0.00% of their portfolio | 672 $1.9k | New |
| ACADIAN ASSET MANAGEMENT LLC 0.00% of their portfolio | 475 $1.0k | New |
| PNC Financial Services Group, Inc. 0.00% of their portfolio | 466 $1.3k | New |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 45 $126 | New |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 36 $102 | New |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 6 $17 | New |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. 0.00% of their portfolio | 0 $0 | New |