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Disclosery

QSI QUANTUM SI INC

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COM CL A (common), issuer CIK 1816431

150 managers (157 13F filers) reported a position in QSI shares at 2026-03-31, 63,116,250 shares in all. 40 filers opened a position and 21 filers sold out during the quarter.

Managers
150
13F filers
157
New
40
Added
39
Reduced
37
Sold out
21
Shares held by filers
63,116,250

Shares held by filers adds up every 13F filer's report, so a share reported by a parent and by its subsidiary counts twice (H9). Managers counts each filer group once.

13D and 13G filers

No 13D or 13G on this security in the data. Structured 13D/G data starts 2024-12-18.

Insider trades

No Form 4 transaction on this security in the data.

13F holders, Q1 2026

Filers in the available 13F reports with a share position at 2026-03-31, filer groups collapsed to one row (method), largest first. Options and principal amounts are left out. A group row states no % of portfolio, since each member reports its own portfolio: the members' percents are listed under it. A value about 1,000 times or 1/1,000 of the price other filers imply is shown as filed but neither ranks the row nor enters a sum.

HolderSharesValue% of portfolioChangeSource
BlackRock, Inc.in group BlackRock, Inc.13,414,949$10.4M<0.01%+360,89213F-HRTimelineGroup
VANGUARD GROUP INCgroup of 5 filers holding9,768,553$7.56M+9,744,754Timeline
ARK Investment Management LLCin group ARK Investment Management LLC6,878,899$5.32M0.04%-142,67213F-HRTimelineGroup
Amova Asset Management Americas, Inc.in group Amova Asset Management Americ…4,391,666$3.43M0.05%-299,05413F-HRTimelineGroup
Sumitomo Mitsui Trust Group, Inc.in group Sumitomo Mitsui Trust Group, …4,391,666$3.4M<0.01%-299,05413F-HRTimelineGroup
GEODE CAPITAL MANAGEMENT, LLCin group GEODE CAPITAL MANAGEMENT, LLC3,835,121$2.97M<0.01%-279,25413F-HRTimelineGroup
STATE STREET CORPin group STATE STREET CORP3,770,689$2.92M<0.01%+207,96813F-HRTimelineGroup
AQR CAPITAL MANAGEMENT LLCin group AQR CAPITAL MANAGEMENT LLC2,392,179$1.85M<0.01%+2,305,49013F-HRTimelineGroup
UBS Group AGin group UBS Group AG1,702,527$1.32M<0.01%+253,01513F-HRTimelineGroup
SUSQUEHANNA INTERNATIONAL GROUP, LLPin group SUSQUEHANNA INTERNATIONAL GRO…1,464,568$1.13M<0.01%-863,21713F-HRTimelineGroup
NORTHERN TRUST CORPin group NORTHERN TRUST CORP1,260,701$976K<0.01%-947,23513F-HRTimelineGroup
Fosun International Ltd743,935$576K0.14%013F-HRTimeline
CHARLES SCHWAB INVESTMENT MANAGEMENT INCin group Charles Schwab Trust Co457,571$354K<0.01%-10,60313F-HRTimelineGroup
Nuveen, LLCin group TIAA451,367$349K<0.01%+3,84813F-HRTimelineGroup
GOLDMAN SACHS GROUP INCin group GOLDMAN SACHS GROUP INC444,177$344K<0.01%+57,35313F-HRTimelineGroup
Invesco Ltd.in group Invesco Ltd.406,690$315K<0.01%+3,86913F-HRTimelineGroup
XTX Topco Ltdin group XTX Topco Ltd389,254$301K0.01%-72,72813F-HRTimelineGroup
ALLIANCEBERNSTEIN L.P.272,180$299K<0.01%013F-HRTimeline
Bank of New York Mellon Corpin group Bank of New York Mellon Corp383,088$297K<0.01%-23,20313F-HRTimelineGroup
IEQ CAPITAL, LLC357,688$277K<0.01%new13F-HRTimeline
Knollwood Investment Advisory, LLC300,000$232K0.02%013F-HRTimeline
IQ EQ FUND MANAGEMENT (IRELAND) Ltd292,107$226K0.02%+38,21213F-HRTimeline
GROUP ONE TRADING LLC283,981$220K0.01%+38,18013F-HRTimeline
BRIDGEWAY CAPITAL MANAGEMENT, LLC261,100$202K<0.01%013F-HRTimeline
IMC-Chicago, LLC220,876$171K<0.01%new13F-HRTimeline
CIBC Bancorp USA Inc.in group CIBC Bancorp USA Inc.208,510$161K<0.01%13F-HRTimelineGroup
Verdence Capital Advisors LLC203,855$158K0.01%+16,05013F-HRTimeline
Mariner, LLCin group Mariner, LLC199,692$155K<0.01%+142,81213F-HRTimelineGroup
RHUMBLINE ADVISERS193,068$149K<0.01%-52713F-HRTimeline
BANK OF AMERICA CORP /DE/in group BANK OF AMERICA CORP /DE/161,987$125K<0.01%-96,45813F-HRTimelineGroup
Shay Capital LLC150,922$117K0.02%+1,79013F-HRTimeline
MORGAN STANLEYin group MORGAN STANLEY129,940$101K<0.01%-270,05413F-HRTimelineGroup
AlphaCore Capital LLC128,449$99.4K<0.01%+79,09913F-HRTimeline
CWM, LLCin group CWM, LLC126,632$98K<0.01%+119,63813F-HRTimelineGroup
DEUTSCHE BANK AG\in group DEUTSCHE BANK AG\119,028$91.7K<0.01%013F-HRTimelineGroup
RENAISSANCE TECHNOLOGIES LLC117,900$91.3K<0.01%new13F-HRTimeline
LOS ANGELES CAPITAL MANAGEMENT LLC116,341$90K<0.01%+23,33113F-HRTimeline
JONES FINANCIAL COMPANIES LLLPin group JONES FINANCIAL COMPANIES LLLP109,900$84K<0.01%+11,00013F-HRTimelineGroup
MetLife Investment Management, LLCin group MetLife Investment Management…101,555$78.6K<0.01%+67,33313F-HRTimelineGroup
PRICE T ROWE ASSOCIATES INC /MD/96,486$75K<0.01%013F-HRTimeline
SIMPLEX TRADING, LLC90,531$70.1K<0.01%+10,02413F-HRTimeline
Mirae Asset Global Investments Co., Ltd.group of 2 filers holding85,128$65.9K+2,655Timeline
Cerity Partners LLCin group Cerity Partners LLC80,650$62.4K<0.01%new13F-HRTimelineGroup
JPMORGAN CHASE & COin group JPMORGAN CHASE & CO83,519$61.6K<0.01%+6,61013F-HR/ATimelineGroup
WEALTH ENHANCEMENT ADVISORY SERVICES, L…89,536$57.9K<0.01%new13F-HRTimeline
CAPTRUST FINANCIAL ADVISORS69,036$53.4K<0.01%+34,43313F-HRTimeline
Virtu Financial LLCin group Virtu Financial LLC64,751$50K<0.01%-173,62813F-HRTimelineGroup
WELLS FARGO & COMPANY/MNin group WELLS FARGO & COMPANY/MN63,868$49.4K<0.01%-112,26413F-HR/ATimelineGroup
Quantbot Technologies LP58,461$45.2K<0.01%new13F-HRTimeline
MERCER GLOBAL ADVISORS INC /ADV55,195$42.7K<0.01%new13F-HRTimeline
TWO SIGMA INVESTMENTS, LPin group TWO SIGMA INVESTMENTS, LP52,924$41K<0.01%-1,331,25713F-HRTimelineGroup
Creative Planningin group Creative Planning52,548$40.7K<0.01%new13F-HRTimelineGroup
MANUFACTURERS LIFE INSURANCE COMPANY, T…in group MANUFACTURERS LIFE INSURANCE …47,453$36.7K<0.01%-91913F-HRTimelineGroup
INTECH INVESTMENT MANAGEMENT LLC46,486$36K<0.01%-19,15013F-HRTimeline
Police & Firemen's Retirement System of…46,170$35.7K<0.01%013F-HRTimeline
Green Alpha Advisors, LLC43,208$33.4K0.03%-8,32013F-HRTimeline
Sanctuary Advisors, LLC42,824$33.1K<0.01%+41113F-HRTimeline
Cambridge Investment Research Advisors,…41,809$32K<0.01%+4,04213F-HRTimeline
STATE BOARD OF ADMINISTRATION OF FLORID…41,282$32K<0.01%013F-HRTimeline
NINE MASTS CAPITAL Ltd41,134$31.8K<0.01%new13F-HRTimeline
HOLLENCREST CAPITAL MANAGEMENT40,111$31K<0.01%+30,11113F-HRTimeline
Focus Partners Wealthgroup of 2 filers holding39,990$31KnewTimeline
BARCLAYS PLCin group BARCLAYS PLC39,137$30.3K<0.01%-230,27813F-HRTimelineGroup
BNP PARIBAS FINANCIAL MARKETSin group BNP PARIBAS FINANCIAL MARKETS38,390$29.7K<0.01%+2,11413F-HRTimelineGroup
Red Wave Investments LLC37,000$28.6K0.01%013F-HRTimeline
Merit Financial Group, LLC36,347$28.1K<0.01%new13F-HRTimeline
JTC Employer Solutions Trustee Ltd34,540$27K<0.01%013F-HRTimeline
China Universal Asset Management Co., L…34,702$26.9K<0.01%+2,83713F-HRTimeline
SG Americas Securities, LLC33,677$26K<0.01%+4,57113F-HRTimeline
ProShare Advisors LLC33,239$25.7K<0.01%-4,10213F-HRTimeline
SEI INVESTMENTS COin group SEI INVESTMENTS CO33,103$25.6K<0.01%013F-HRTimelineGroup
SBI Securities Co., Ltd.32,133$24.9K<0.01%-2,03013F-HRTimeline
FMR LLCin group FMR LLC31,968$24.7K<0.01%-65,95713F-HRTimelineGroup
Northern Lights Advisors, Inc.29,989$23.2K0.02%013F-HRTimeline
COMMONWEALTH EQUITY SERVICES, LLC29,792$23.1K<0.01%+1,83213F-HRTimeline
BRIGHTON JONES LLC27,560$21.3K<0.01%new13F-HR/ATimeline
VOYA INVESTMENT MANAGEMENT LLCin group VOYA INVESTMENT MANAGEMENT LLC27,246$21.1K<0.01%013F-HRTimelineGroup
Wealth Management Associates, Inc.26,950$20.9K0.01%013F-HRTimeline
NEW YORK STATE COMMON RETIREMENT FUND26,084$20.2K<0.01%013F-HRTimeline
Pallas Capital Advisors LLC25,757$19.9K<0.01%new13F-HRTimeline
Kovack Advisors, Inc.30,000$19.7K<0.01%+13,20013F-HRTimeline
Leonteq Securities AG25,000$19.4K<0.01%013F-HRTimeline
Tower Research Capital LLC (TRC)in group Tower Research Capital LLC (T…24,943$19.3K<0.01%-7,65213F-HRTimelineGroup
HBW ADVISORY SERVICES LLC22,697$17.6K<0.01%-1,46613F-HRTimeline
Krilogy Financial LLC16,729$17.4K<0.01%new13F-HRTimeline
LPL Financial LLC22,467$17.4K<0.01%-2,75013F-HRTimeline
PRUDENTIAL FINANCIAL INCin group PRUDENTIAL FINANCIAL INC21,570$16.7K<0.01%new13F-HRTimelineGroup
Capital Investment Advisory Services, L…20,000$15.5K<0.01%013F-HRTimeline
VICTORY CAPITAL MANAGEMENT INC19,808$15.3K<0.01%+1113F-HRTimeline
DLK Investment Management, LLC16,750$13K0.01%new13F-HRTimeline
NewEdge Advisors, LLC15,820$12.2K<0.01%+1,77813F-HR/ATimeline
CITADEL ADVISORS LLCin group CITADEL ADVISORS LLC15,546$12K<0.01%-2,660,55113F-HRTimelineGroup
Essential Partners LLC15,436$11.9K<0.01%new13F-HRTimeline
Stratos Wealth Advisors, LLCin group Stratos Wealth Partners, LTD.15,036$11.6K<0.01%013F-HRTimelineGroup
Integrated Wealth Concepts LLC14,499$11.2K<0.01%new13F-HRTimeline
Ameritas Investment Partners, Inc.in group Ameritas Investment Partners,…14,401$11.1K<0.01%013F-HRTimelineGroup
Flagship Private Wealth, LLC14,158$11K<0.01%013F-HRTimeline
XPONANCE LLC13,849$10.7K<0.01%+2,02513F-HRTimeline
Procyon Advisors, LLC13,671$10.6K<0.01%013F-HRTimeline
CITIGROUP INCin group CITIGROUP INC13,314$10.3K<0.01%-6,46213F-HRTimelineGroup
Legal & General Group Plcin group Legal & General Group Plc12,860$9.95K<0.01%013F-HRTimelineGroup
Graham Capital Management, L.P.12,220$9.46K<0.01%-2,20213F-HRTimeline
Russell Investments Group, Ltd.in group Russell Investments Group, Lt…11,848$9.17K<0.01%-15,04513F-HRTimelineGroup
NorthCrest Asset Manangement, LLC12,144$9.08K<0.01%new13F-HRTimeline
Curi Capital, LLC10,391$8.04K<0.01%new13F-HRTimeline
Cresset Asset Management, LLC10,207$7.9K<0.01%013F-HRTimeline
Ground Swell Capital, LLC10,132$7.84K0.02%new13F-HRTimeline
Glen Eagle Advisors, LLC10,000$7.74K<0.01%013F-HRTimeline
RED REEF ADVISORS LLC10,000$7.74K0.01%013F-HRTimeline
Kestra Advisory Services, LLCgroup of 2 filers holding10,000$7.74K-90Timeline
CALIFORNIA STATE TEACHERS RETIREMENT SY…8,500$6.58K<0.01%-1,16113F-HRTimeline
OSAIC HOLDINGS, INC.in group OSAIC HOLDINGS, INC.7,970$6.14K<0.01%+86913F-HRTimelineGroup
Allworth Financial LP6,829$5.29K<0.01%+6,39313F-HRTimeline
WOLVERINE ASSET MANAGEMENT LLCin group WOLVERINE ASSET MANAGEMENT LLC6,170$4.78K<0.01%013F-HRTimelineGroup
Sterling Capital Management LLC5,672$4.39K<0.01%-3,38213F-HRTimeline
EverSource Wealth Advisors, LLCin group EverSource Wealth Advisors, L…5,455$4.22K<0.01%+5,02813F-HR/ATimelineGroup
Blue Trust, Inc.5,000$3.87K<0.01%013F-HRTimeline
MTM Investment Management, LLC4,125$3.19K<0.01%013F-HRTimeline
FNY Investment Advisers, LLC4,000$3K<0.01%013F-HRTimeline
N.E.W. Advisory Services LLC3,854$2.98K<0.01%013F-HRTimeline
GF FUND MANAGEMENT CO. LTD.3,723$2.88K<0.01%013F-HRTimeline
PINNEY & SCOFIELD, INC.3,680$2.85K<0.01%013F-HRTimeline
IFP Advisors, Inc2,101$1.63K<0.01%new13F-HRTimeline
Steward Partners Investment Advisory, L…2,000$1.55K<0.01%new13F-HRTimeline
Archer Investment Corp2,000$1.55K<0.01%013F-HRTimeline
GAMMA Investing LLC1,830$1.42K<0.01%-5,16113F-HRTimeline
ROTHSCHILD INVESTMENT LLC1,688$1.31K<0.01%+1,61813F-HRTimeline
Arax Advisory Partners1,364$1.06K<0.01%new13F-HRTimeline
Hanson & Doremus Investment Management1,300$1K<0.01%new13F-HRTimeline
Farther Finance Advisors, LLC1,334$997<0.01%new13F-HRTimeline
MAI Capital Management1,274$987<0.01%new13F-HRTimeline
Sound Income Strategies, LLC1,000$748<0.01%013F-HRTimeline
Optiver Holding B.V.in group Optiver Holding B.V.806$624<0.01%-12113F-HR/ATimelineGroup
Walleye Capital LLCgroup of 2 filers holding760$588+702Timeline
Wealth Preservation Advisors, LLC549$425<0.01%new13F-HRTimeline
Rialto Wealth Management, LLC509$394<0.01%new13F-HRTimeline
True Wealth Design, LLC507$393<0.01%new13F-HRTimeline
Medallion Wealth Advisors, LLC470$363<0.01%013F-HRTimeline
NISA INVESTMENT ADVISORS, LLC382$296<0.01%-22613F-HRTimeline
Caitong International Asset Management …305$236<0.01%-37,65913F-HRTimeline
Root Financial Partners, LLC292$226<0.01%new13F-HRTimeline
TD Waterhouse Canada Inc.300$224<0.01%-50013F-HRTimeline
HARBOUR INVESTMENTS, INC.250$194<0.01%new13F-HRTimeline
GILL CAPITAL PARTNERS, LLC200$155<0.01%new13F-HRTimeline
Sunbelt Securities, Inc.143$111<0.01%new13F-HRTimeline
SJS Investment Consulting Inc.119$93<0.01%new13F-HRTimeline
Bangor Savings Bank105$81<0.01%new13F-HRTimeline
Federation des caisses Desjardins du Qu…50$39<0.01%013F-HRTimeline
Kilter Group LLC4$4<0.01%new13F-HRTimeline
ROYAL BANK OF CANADAin group ROYAL BANK OF CANADA109$00%-4,35813F-HRTimelineGroupValue filed as zero, left out of ratios.