FUEL TECH INC FTEK
COM · Common Stock · CUSIP 359523107
- SectorIndustrials
- IndustryIndustrial & Commercial Fans & Blowers & Air Purifing Equip
- HeadquartersWarrenville, IL
- 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: 31.1m as of 2025-10-31, 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 ≈ $1.56. Options: 3 managers hold calls ($141.3k notional), 2 hold puts ($37.1k).
Trends to Q4 2025
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 37 |
| Q4 2022 | 42 |
| Q1 2023 | 38 |
| Q2 2023 | 41 |
| Q3 2023 | 39 |
| Q4 2023 | 37 |
| Q1 2024 | 34 |
| Q2 2024 | 35 |
| Q3 2024 | 37 |
| Q4 2024 | 40 |
| Q1 2025 | 36 |
| Q2 2025 | 37 |
| Q3 2025 | 48 |
| Q4 2025 | 45 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q1 2024 | 10 | 13 |
| Q2 2024 | 12 | 10 |
| Q3 2024 | 16 | 7 |
| Q4 2024 | 16 | 9 |
| Q1 2025 | 15 | 16 |
| Q2 2025 | 15 | 16 |
| Q3 2025 | 27 | 13 |
| Q4 2025 | 22 | 20 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q1 2025 | $46.8k | $11.6k | 0.25 |
| Q2 2025 | $35.8k | $310.5k | 8.68 |
| Q3 2025 | $930.2k | $59.0k | 0.06 |
| Q4 2025 | $141.3k | $37.1k | 0.26 |
Biggest buyers
| CITADEL ADVISORS LLC | Added | +377.0k |
| RENAISSANCE TECHNOLOGIES LLC | Added | +249.1k |
| TWO SIGMA INVESTMENTS, LP | New | +126.2k |
| XTX Topco Ltd | Added | +122.3k |
| VANGUARD GROUP INC | Added | +112.1k |
| MARSHALL WACE, LLP | New | +81.0k |
| TWO SIGMA ADVISERS, LP | New | +67.5k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | +28.0k |
| JANE STREET GROUP, LLC | Added | +23.9k |
| Virtu Financial LLC | New | +17.3k |
Biggest sellers
| Informed Momentum Co LLC | Sold out | -338.7k |
| Mercuria Capital Strategies, LLC | Sold out | -240.0k |
| Murchinson Ltd. | Sold out | -150.0k |
| BOOTHBAY FUND MANAGEMENT, LLC | Sold out | -41.3k |
| SIMPLEX TRADING, LLC | Reduced | -39.2k |
| Integrated Wealth Concepts LLC | Sold out | -35.0k |
| GOLDMAN SACHS GROUP INC | Sold out | -31.3k |
| HRT FINANCIAL LP | Sold out | -23.3k |
| Advisory Services Network, LLC | Sold out | -21.6k |
| NewEdge Advisors, LLC | Reduced | -15.3k |
Biggest calls
| JANE STREET GROUP, LLC | New | $72.7k46.6k shares |
| CITADEL ADVISORS LLC | Reduced | $49.6k31.8k shares |
| SIMPLEX TRADING, LLC | Reduced | $19.0k12.2k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | New | $33.2k21.3k shares |
| SIMPLEX TRADING, LLC | Unchanged | $3.9k2.5k 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.
No one currently above 5% in the filings since 19 Dec 2024.
Fell to 5% or below in the last year: GRACE & WHITE INC /NY (4.9%, 2026-10-07)
Insider purchases and sales in Q4 2025
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 |
|---|---|---|---|---|---|
| Q1 2024 | 0 | — | 0 | — | — |
| Q2 2024 | 0 | — | 0 | — | — |
| Q3 2024 | 3 | $50.0k | 0 | — | — |
| Q4 2024 | 1 | $50.1k | 0 | — | — |
| Q1 2025 | 1 | $15.8k | 0 | — | — |
| Q2 2025 | 0 | — | 1 | $21.1k | — |
| Q3 2025 | 0 | — | 0 | — | — |
| Q4 2025 | 0 | — | 0 | — | — |
None reported in Q4 2025.
Holders, Q4 2025
| Manager | Shares | Change |
|---|---|---|
| GRACE & WHITE INC /NY 0.41% of their portfolio | 1.5m $2.3m | Reduced -5.8k |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 1.1m $1.8m | Added +249.1k |
| VANGUARD GROUP INC 0.00% of their portfolio | 1.1m $1.8m | Added +112.1k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 518.9k $809.6k | Reduced -4.9k |
| CITADEL ADVISORS LLC 0.00% of their portfolio | 504.0k $786.3k | Added +377.0k |
| BlackRock, Inc. 0.00% of their portfolio | 410.4k $640.2k | Unchanged |
| Peapod Lane Capital LLC 0.48% of their portfolio | 359.6k $561.0k | Added +2.7k |
| US BANCORP \DE\ 0.00% of their portfolio | 304.8k $475.5k | Unchanged |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 260.8k $406.8k | Added +23.9k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio | 238.0k $371.2k | Added +28.0k |
| XTX Topco Ltd 0.01% of their portfolio | 178.3k $278.2k | Added +122.3k |
| Beartown Capital Management, LLC 0.20% of their portfolio | 160.0k $249.6k | First filing |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 126.2k $196.8k | New |
| STATE STREET CORP 0.00% of their portfolio | 121.8k $190.1k | Added +8.1k |
| MARSHALL WACE, LLP 0.00% of their portfolio | 81.0k $126.4k | New |
| ESSEX INVESTMENT MANAGEMENT CO LLC 0.02% of their portfolio | 77.2k $120.5k | Unchanged |
| INTEGRITY WEALTH ADVISORS, INC. 0.07% of their portfolio | 70.0k $95.2k | Unchanged |
| TWO SIGMA ADVISERS, LP 0.00% of their portfolio | 67.5k $105.3k | New |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 51.2k $79.7k | Reduced -3.2k |
| GROUP ONE TRADING LLC 0.00% of their portfolio | 42.5k $66.3k | Added +12.3k |
| AMERICAN CENTURY COMPANIES INC 0.00% of their portfolio | 38.5k $60.1k | Added +2.0k |
| GSA CAPITAL PARTNERS LLP 0.00% of their portfolio | 32.0k $50.0k | Reduced -4.5k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 31.4k $49.0k | Unchanged |
| Cresset Asset Management, LLC 0.00% of their portfolio | 25.5k $39.8k | Unchanged |
| Legato Capital Management LLC 0.00% of their portfolio | 18.2k $28.3k | Unchanged |
| Virtu Financial LLC 0.00% of their portfolio | 17.3k $27.0k | New |
| TWO SIGMA SECURITIES, LLC 0.00% of their portfolio | 14.6k $22.7k | New |
| Covestor Ltd 0.01% of their portfolio | 13.2k $21.0k | Unchanged |
| Quadrature Capital Ltd 0.00% of their portfolio | 11.6k $18.1k | New |
| HighTower Advisors, LLC 0.00% of their portfolio | 10.4k $16.3k | Added +40 |
| Founders Capital Management 0.00% of their portfolio | 5.0k $7.8k | Unchanged |
| Tower Research Capital LLC (TRC) 0.00% of their portfolio | 4.3k $6.7k | New |
| SIMPLEX TRADING, LLC 0.00% of their portfolio | 3.3k $5.1k | Reduced -39.2k |
| NewEdge Advisors, LLC 0.00% of their portfolio | 2.3k $3.6k | Reduced -15.3k |
| New England Capital Financial Advisors LLC 0.00% of their portfolio | 2.0k $3.1k | Unchanged |
| OSAIC HOLDINGS, INC. 0.00% of their portfolio | 1.2k $1.9k | Unchanged |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 1.1k $1.8k | Reduced -2.5k |
| SBI Securities Co., Ltd. 0.00% of their portfolio | 719 $1.1k | Reduced -110 |
| Steward Partners Investment Advisory, LLC 0.00% of their portfolio | 600 $936 | Unchanged |
| Wilmington Savings Fund Society, FSB 0.00% of their portfolio | 500 $780 | Unchanged |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 280 $437 | Added +63 |
| CKW FINANCIAL GROUP 0.00% of their portfolio | 200 $0 | Unchanged |
| Motiv8 Investments LLC 0.00% of their portfolio | 100 $0 | New |
| MORGAN STANLEY 0.00% of their portfolio | 21 $33 | New |
| FMR LLC 0.00% of their portfolio | 18 $28 | New |