Vault-13

SYNLOGIC INC SYBX

COM NEW · Common Stock · CUSIP 87166L209

28 institutional holders
2,661,8402.7m shares reported held*
29.0% of all shares outstanding*
$7.3mreported value*

* 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 +646,846+646.8k
ARMISTICE CAPITAL, LLC New +599,874+599.9k
ORBIMED ADVISORS LLC New +401,998+402.0k
NEA Management Company, LLC New +281,929+281.9k
Atlas Venture Associates IX, LLC New +176,798+176.8k
Alyeska Investment Group, L.P. New +168,034+168.0k
VANGUARD GROUP INC New +149,571+149.6k
Sofinnova Investments, Inc. New +38,331+38.3k
GEODE CAPITAL MANAGEMENT, LLC New +30,326+30.3k
Fiduciary Trust Co New +22,353+22.4k

Biggest sellers

None

Biggest calls

Biggest puts

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.

HolderStakeChangeShares Last filed
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% no change 3.3m 2026-07-29
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% 2.9m 2026-07-29
Baselake Partners, LP 13G · passive investor new · filed 2026-01-23 9.7% new 1.1m 2026-01-23

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)

BuyingSelling
404Q4 21: 0 buyingQ4 21: 0 sellingQ1 22: 0 buyingQ1 22: 0 sellingQ1 22Q2 22: 1 buyingQ2 22: 2 sellingQ3 22: 0 buyingQ3 22: 0 sellingQ3 22Q4 22: 0 buyingQ4 22: 0 sellingQ1 23: 0 buyingQ1 23: 0 sellingQ1 23Q2 23: 0 buyingQ2 23: 3 sellingQ3 23: 0 buyingQ3 23: 0 sellingQ3 23
Numbers
QuarterBuyingBoughtSellingSoldSold under a plan
Q4 20210—0——
Q1 20220—0——
Q2 20221$10.6k2$28.3k—
Q3 20220—0——
Q4 20220—0——
Q1 20230—0——
Q2 20230—3——
Q3 20230—0——

None reported in Q3 2023.

Holders, Q3 2023

#ManagerLocationShares Value% of their portfolioChangeShares change
1 FMR LLC 0.00% of their portfolio BOSTON, MA 646,846646.8k $1.8m $1.8m 0.00% New
2 ARMISTICE CAPITAL, LLC 0.05% of their portfolio NEW YORK, NY 599,874599.9k $1.7m $1.7m 0.05% New
3 ORBIMED ADVISORS LLC 0.02% of their portfolio New York, NY 401,998402.0k $1.1m $1.1m 0.02% New
4 NEA Management Company, LLC 0.05% of their portfolio TIMONIUM, MD 281,929281.9k $614.6k $614.6k 0.05% New
5 Atlas Venture Associates IX, LLC 4.23% of their portfolio Boston, MA 176,798176.8k $496.8k $496.8k 4.23% New
6 Alyeska Investment Group, L.P. 0.00% of their portfolio CHICAGO, IL 168,034168.0k $472.2k $472.2k 0.00% New
7 VANGUARD GROUP INC 0.00% of their portfolio Valley Forge, PA 149,571149.6k $420.3k $420.3k 0.00% New
8 OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AMERICAS (LLC) 0.00% of their portfolio CHICAGO, IL 40,54840.5k $113.9k $113.9k 0.00% Not comparable
9 Sofinnova Investments, Inc. 0.01% of their portfolio Menlo Park, CA 38,33138.3k $107.7k $107.7k 0.01% New
10 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 30,32630.3k $85.2k $85.2k 0.00% New
11 Fiduciary Trust Co 0.00% of their portfolio Boston, MA 22,35322.4k $62.8k $62.8k 0.00% New
12 HARBOR CAPITAL ADVISORS, INC. 0.01% of their portfolio CHICAGO, IL 21,40321.4k $60.1k $60.1k 0.01% New
13 Ikarian Capital, LLC 0.02% of their portfolio DALLAS, TX 20,44820.4k $57.5k $57.5k 0.02% New
14 BlackRock Inc. 0.00% of their portfolio New York, NY 20,00520.0k $56.2k $56.2k 0.00% New
15 WINTON GROUP Ltd 0.00% of their portfolio LONDON, X0 12,40112.4k $34.8k $34.8k 0.00% New
16 GOLDMAN SACHS GROUP INC 0.00% of their portfolio NEW YORK, NY 11,01211.0k $30.9k $30.9k 0.00% New
17 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 10,28210.3k $28.9k $28.9k 0.00% New
18 OSAIC HOLDINGS, INC. 0.00% of their portfolio SCOTTSDALE, AZ 3,2453.2k $9.1k $9.1k 0.00% New
19 Ensign Peak Advisors, Inc 0.00% of their portfolio SALT LAKE CITY, UT 2,2072.2k $6.2k $6.2k 0.00% New
20 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 1,6321.6k $4.6k $4.6k 0.00% New
21 ROYAL BANK OF CANADA 0.00% of their portfolio TORONTO, A6 897897 $3.0k $3.0k 0.00% New
22 Tower Research Capital LLC (TRC) 0.00% of their portfolio NEW YORK, NY 672672 $1.9k $1.9k 0.00% New
23 ACADIAN ASSET MANAGEMENT LLC 0.00% of their portfolio Boston, MA 475475 $1.0k $1.0k 0.00% New
24 PNC Financial Services Group, Inc. 0.00% of their portfolio Pittsburgh, PA 466466 $1.3k $1.3k 0.00% New
25 RHUMBLINE ADVISERS 0.00% of their portfolio BOSTON, MA 4545 $126 $126 0.00% New
26 WELLS FARGO & COMPANY/MN 0.00% of their portfolio SAN FRANCISCO, CA 3636 $102 $102 0.00% New
27 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 66 $17 $17 0.00% New
28 CONCOURSE FINANCIAL GROUP SECURITIES, INC. 0.00% of their portfolio BIRMINGHAM, AL 00 $0 $0 0.00% New