Ownership

Who owns Arqit Quantum Inc, from the filings themselves: stakes over 5% (Schedule 13D/G), the institutional managers reporting the stock each quarter (13F), and the funds holding it (N-PORT).

Stakes over 5%

Investors crossing 5% ownership must disclose it. Schedule 13G filers certify the stake is passive; Schedule 13D is the general form for everyone else — founders, strategic holders, and activists alike. Each entry is the holder's most recent disclosure. Coverage begins with SEC's structured filings from December 18, 2024; a holder appears once they file or amend after that date.

ICS Opportunities, Ltd., Millennium Management LLC, Millennium Group Management LLC June 23, 2026

ICS Opportunities, Ltd.: 0.0% · 7,800 shares — Millennium Management LLC: 0.3% · 58,621 shares — Millennium Group Management LLC: 0.3% · 58,621 shares

View filing (SCHEDULE 13G)

Heritage Assets SCSp, M Management S.A., Manfredi Lefebvre d'Ovidio May 26, 2026

Heritage Assets SCSp: 38.4% · 9,249,963 shares — M Management S.A.: 38.4% · 9,249,963 shares — Manfredi Lefebvre d'Ovidio: 38.6% · 9,298,313 shares

View filing (SCHEDULE 13D/A) Amendment #9

2 more 5% stakes behind a free account

See every investor who has disclosed crossing 5% of Arqit Quantum Inc.

Super investors holding ARQQ

Every institutional manager whose latest 13F reports this stock, largest position first. "% of their portfolio" is the weight inside that manager's own book — how much conviction the position represents; "% of company" is how much of Arqit Quantum Inc they hold. Together these 89 managers report 81.75% of shares outstanding.

Investor	Position value	Shares	% of their portfolio	% of company	As of
Penserra Capital Management LLC	$151M	5,081,219	1.16%	33.23%	June 30, 2026
Defiance ETFs, LLC	$147M	5,099,023	2.00%	33.34%	June 30, 2026

87 more institutional holders behind a free account

See every manager reporting Arqit Quantum Inc, how much of the company they hold, and how big the position is inside their own portfolio.

Funds holding ARQQ

Funds disclosing this stock in their monthly N-PORT portfolio, with the position's share of the fund's net assets. Together these 2 funds hold 2.14% of shares outstanding — counted inside the manager totals above, not on top of them, since a fund's shares also appear in its manager's 13F.

Fund	Position value	% of net assets	% of company	As of
Global X Cybersecurity ETF	$4.88M	0.61%	1.94%	February 28, 2026
Mango Growth ETF	$442K	0.17%	0.20%	April 30, 2026