Vault-13

FUEL TECH INC FTEK

COM · Common Stock · CUSIP 359523107

46 institutional holders +1 vs Q4 2025
7,559,7027.6m shares reported held*
24.3% of all shares outstanding*
$9.2mreported value*
6 new 8 added 13 reduced 7 sold out net sold ≈ $25.5k (-20.9k shares)

* 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: 31.2m as of 2026-04-30, 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 ≈ $1.22. Options: 0 managers hold calls (— notional), 1 hold puts ($36.2k).

Trends to Q1 2026

Institutional holders

Managers reporting a position, each quarter

0204060Q3 22: 37Q4 22: 42Q1 23: 38Q2 23: 41Q3 23: 39Q4 23: 37Q1 24: 34Q2 24: 35Q3 24: 37Q4 24: 40Q1 25: 36Q2 25: 37Q3 25: 48Q4 25: 45Q1 26: 4646Q3 22Q3 23Q3 24Q3 25Q1 26
Numbers
QuarterHolders
Q3 202237
Q4 202242
Q1 202338
Q2 202341
Q3 202339
Q4 202337
Q1 202434
Q2 202435
Q3 202437
Q4 202440
Q1 202536
Q2 202537
Q3 202548
Q4 202545
Q1 202646

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
40040Q2 24: 12 bought or addedQ2 24: 10 cut or sold outQ3 24: 16 bought or addedQ3 24: 7 cut or sold outQ3 24Q4 24: 16 bought or addedQ4 24: 9 cut or sold outQ1 25: 15 bought or addedQ1 25: 16 cut or sold outQ1 25Q2 25: 15 bought or addedQ2 25: 16 cut or sold outQ3 25: 27 bought or addedQ3 25: 13 cut or sold outQ3 25Q4 25: 22 bought or addedQ4 25: 20 cut or sold outQ1 26: 14 bought or addedQ1 26: 20 cut or sold outQ1 26
Numbers
QuarterBought or addedCut or sold out
Q2 20241210
Q3 2024167
Q4 2024169
Q1 20251516
Q2 20251516
Q3 20252713
Q4 20252220
Q1 20261420

Calls vs puts

Options held, notional value, last 4 quarters. P/C = puts ÷ calls

CallsPuts
$0$250k$500k$750k$1mQ2 25 calls: $35.8kQ2 25 puts: $310.5kQ2 25P/C 8.68Q3 25 calls: $930.2kQ3 25 puts: $59.0kQ3 25P/C 0.06Q4 25 calls: $141.3kQ4 25 puts: $37.1kQ4 25P/C 0.26Q1 26 calls: $0Q1 26 puts: $36.2kQ1 26P/C —
Numbers
QuarterCallsPutsP/C
Q2 2025$35.8k$310.5k8.68
Q3 2025$930.2k$59.0k0.06
Q4 2025$141.3k$37.1k0.26
Q1 2026$0$36.2k—

Biggest buyers

RENAISSANCE TECHNOLOGIES LLC Added +259,811+259.8k
GSA CAPITAL PARTNERS LLP Added +214,241+214.2k
Peapod Lane Capital LLC Added +119,199+119.2k
TWO SIGMA INVESTMENTS, LP Added +111,919+111.9k
GRACE & WHITE INC /NY Added +55,424+55.4k
INTEGRITY WEALTH ADVISORS, INC. Added +45,000+45.0k
Integrated Wealth Concepts LLC New +35,000+35.0k
Chicago Partners Investment Group LLC New +17,088+17.1k
GEODE CAPITAL MANAGEMENT, LLC Added +13,869+13.9k
Founders Capital Management Added +1,000+1.0k

Biggest sellers

CITADEL ADVISORS LLC Reduced -282,618-282.6k
JANE STREET GROUP, LLC Reduced -189,985-190.0k
SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced -97,884-97.9k
TWO SIGMA ADVISERS, LP Sold out -67,500-67.5k
XTX Topco Ltd Reduced -60,056-60.1k
MARSHALL WACE, LLP Reduced -59,241-59.2k
AMERICAN CENTURY COMPANIES INC Sold out -38,543-38.5k
DIMENSIONAL FUND ADVISORS LP Reduced -31,771-31.8k
Virtu Financial LLC Sold out -17,254-17.3k
TWO SIGMA SECURITIES, LLC Sold out -14,583-14.6k

Biggest calls

None

Biggest puts

SUSQUEHANNA INTERNATIONAL GROUP, LLP Added $36.2k29.7k 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 Q1 2026

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
404Q2 24: 0 buyingQ2 24: 0 sellingQ3 24: 3 buyingQ3 24: 0 sellingQ3 24Q4 24: 1 buyingQ4 24: 0 sellingQ1 25: 1 buyingQ1 25: 0 sellingQ1 25Q2 25: 0 buyingQ2 25: 1 sellingQ3 25: 0 buyingQ3 25: 0 sellingQ3 25Q4 25: 0 buyingQ4 25: 0 sellingQ1 26: 1 buyingQ1 26: 0 sellingQ1 26
Numbers
QuarterBuyingBoughtSellingSoldSold under a plan
Q2 20240—0——
Q3 20243$50.0k0——
Q4 20241$50.1k0——
Q1 20251$15.8k0——
Q2 20250—1$21.1k—
Q3 20250—0——
Q4 20250—0——
Q1 20261$12.4k0——
DateInsiderTradeSharesPrice ValueTheir holding
2026-03-06 ARNONE VINCENT J President & CEO, director Bought 10,000 $1.24 $12.4k10.0k shares +2%

Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).

Holders, Q1 2026

#ManagerLocationShares Value% of their portfolioChangeShares change
1 GRACE & WHITE INC /NY 0.33% of their portfolio NY, NY 1,541,3071.5m $1.9m $1.9m 0.33% Added +55.4k +55,424
2 RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio NEW YORK, NY 1,407,8061.4m $1.7m $1.7m 0.00% Added +259.8k +259,811
3 VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio MALVERN, PA 987,998988.0k $1.2m $1.2m 0.00% First filing
4 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 532,808532.8k $650.1k $650.1k 0.00% Added +13.9k +13,869
5 Peapod Lane Capital LLC 0.48% of their portfolio Bedford Hills, NY 478,842478.8k $582.1k $582.1k 0.48% Added +119.2k +119,199
6 BlackRock, Inc. 0.00% of their portfolio New York, NY 410,364410.4k $500.6k $500.6k 0.00% Unchanged
7 US BANCORP \DE\ 0.00% of their portfolio MINNEAPOLIS, MN 304,776304.8k $371.8k $371.8k 0.00% Unchanged
8 GSA CAPITAL PARTNERS LLP 0.02% of their portfolio LONDON, X0 246,252246.3k $300.0k $300.0k 0.02% Added +214.2k +214,241
9 TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio NEW YORK, NY 238,079238.1k $290.5k $290.5k 0.00% Added +111.9k +111,919
10 CITADEL ADVISORS LLC 0.00% of their portfolio MIAMI, FL 221,399221.4k $270.1k $270.1k 0.00% Reduced -282.6k -282,618
11 Beartown Capital Management, LLC 0.14% of their portfolio HUNTINGTON WOODS, MI 146,689146.7k $179.0k $179.0k 0.14% Reduced -13.3k -13,338
12 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio BALA CYNWYD, PA 140,092140.1k $170.9k $170.9k 0.00% Reduced -97.9k -97,884
13 VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio MALVERN, PA 132,505132.5k $161.7k $161.7k 0.00% First filing
14 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 121,846121.8k $148.7k $148.7k 0.00% Unchanged
15 XTX Topco Ltd 0.00% of their portfolio LONDON, X0 118,247118.2k $144.3k $144.3k 0.00% Reduced -60.1k -60,056
16 INTEGRITY WEALTH ADVISORS, INC. 0.08% of their portfolio Ventura, CA 115,000115.0k $140.3k $140.3k 0.08% Added +45.0k +45,000
17 ESSEX INVESTMENT MANAGEMENT CO LLC 0.01% of their portfolio BOSTON, MA 77,25077.2k $94.2k $94.2k 0.01% Unchanged
18 JANE STREET GROUP, LLC 0.00% of their portfolio NEW YORK, NY 70,79770.8k $86.4k $86.4k 0.00% Reduced -190.0k -189,985
19 GROUP ONE TRADING LLC 0.00% of their portfolio CHICAGO, IL 40,21540.2k $49.1k $49.1k 0.00% Reduced -2.3k -2,294
20 Integrated Wealth Concepts LLC 0.00% of their portfolio WALTHAM, MA 35,00035.0k $42.7k $42.7k 0.00% New
21 NORTHERN TRUST CORP 0.00% of their portfolio CHICAGO, IL 31,43531.4k $38.4k $38.4k 0.00% Unchanged
22 Cresset Asset Management, LLC 0.00% of their portfolio Chicago, IL 25,50025.5k $31.1k $31.1k 0.00% Unchanged
23 MARSHALL WACE, LLP 0.00% of their portfolio LONDON, X0 21,77021.8k $26.6k $26.6k 0.00% Reduced -59.2k -59,241
24 DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio AUSTIN, TX 19,42819.4k $23.6k $23.6k 0.00% Reduced -31.8k -31,771
25 Legato Capital Management LLC 0.00% of their portfolio San Francisco, CA 18,16518.2k $22.2k $22.2k 0.00% Unchanged
26 Chicago Partners Investment Group LLC 0.00% of their portfolio CHICAGO, IL 17,08817.1k $23.1k $23.1k 0.00% New
27 LexAurum Advisors, LLC 0.00% of their portfolio OVERLAND PARK, KS 14,16014.2k $17.3k $17.3k 0.00% First filing
28 Covestor Ltd 0.01% of their portfolio LONDON, X0 12,42612.4k $15.0k $15.0k 0.01% Reduced -761 -761
29 HighTower Advisors, LLC 0.00% of their portfolio CHICAGO, IL 10,44010.4k $12.7k $12.7k 0.00% Unchanged
30 Founders Capital Management 0.00% of their portfolio HOUSTON, TX 6,0006.0k $7.3k $7.3k 0.00% Added +1.0k +1,000
31 Vanguard Global Advisers, LLC 0.00% of their portfolio MALVERN, PA 5,5005.5k $6.7k $6.7k 0.00% First filing
32 Tower Research Capital LLC (TRC) 0.00% of their portfolio NEW YORK, NY 3,2113.2k $3.9k $3.9k 0.00% Reduced -1.1k -1,077
33 New England Capital Financial Advisors LLC 0.00% of their portfolio MERIDEN, CT 2,0002.0k $2.4k $2.4k 0.00% Unchanged
34 OSAIC HOLDINGS, INC. 0.00% of their portfolio SCOTTSDALE, AZ 1,2001.2k $1.5k $1.5k 0.00% Unchanged
35 SIMPLEX TRADING, LLC 0.00% of their portfolio CHICAGO, IL 1,0041.0k $1.2k $1.2k 0.00% Reduced -2.3k -2,295
36 Advisory Services Network, LLC 0.00% of their portfolio ATLANTA, GA 900900 $1.1k $1.1k 0.00% New
37 SBI Securities Co., Ltd. 0.00% of their portfolio TOKYO, M0 710710 $866 $866 0.00% Reduced -9 -9
38 Steward Partners Investment Advisory, LLC 0.00% of their portfolio STAMFORD, CT 600600 $732 $732 0.00% Unchanged
39 Wilmington Savings Fund Society, FSB 0.00% of their portfolio WILMINGTON, DE 500500 $610 $610 0.00% Unchanged
40 CKW FINANCIAL GROUP 0.00% of their portfolio HONOLULU, HI 200200 $0 $0 0.00% Unchanged
41 Orion Capital Management LLC 0.00% of their portfolio CORONADO, CA 100100 $122 $122 0.00% New
42 NewEdge Advisors, LLC 0.00% of their portfolio NEW ORLEANS, LA 5050 $61 $61 0.00% Reduced -2.3k -2,277
43 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 2121 $26 $26 0.00% Unchanged
44 FMR LLC 0.00% of their portfolio BOSTON, MA 1818 $22 $22 0.00% Unchanged
45 Caitong International Asset Management Co., Ltd 0.00% of their portfolio HONG KONG, K3 33 $4 $4 0.00% New
46 UBS Group AG 0.00% of their portfolio ZURICH, V8 11 $1 $1 0.00% New