Who owns Calamos S&P 500 Structured Alt Protection ETF – October?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of CPSO from SEC Form 13F filings across 21 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 21 institutions disclosed 577,963 shares of Calamos S&P 500 Structured Alt Protection ETF – October worth $15.5M — about 60.9% of shares outstanding; the largest disclosed holder is Calamos Advisors LLC. Source: SEC Form 13F filings, parsed by EvidInvest.
21
13F holders
$15.5M
value, 2026 filers
60.9%
of shares outstanding (577,963 sh)
3
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of CPSO's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | Calamos Advisors LLC | 344,453 | $9.6M | 0.0% | 36.3% | -3.3% |
| 2 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 57,083 | $1.6M | 0.0% | 6% | +114.3% |
| 3 | COMMONWEALTH EQUITY SERVICES, LLC | 24,062 | $669,880 | 0.0% | 2.5% | 0.0% |
| 4 | Blue Water Asset Management | 20,481 | $570,191 | 0.2% | 2.2% | -33.5% |
| 5 | Calamos Wealth Management LLC | 19,867 | $553,097 | 0.0% | 2.1% | -21.9% |
| 6 | Rooted Wealth Advisors, Inc. | 12,486 | $347,610 | 0.1% | 1.3% | 0.0% |
| 7 | Grantvest Financial Group LLC | 11,888 | $330,962 | 0.2% | 1.3% | -19.0% |
| 8 | HARBOUR INVESTMENTS, INC. | 11,509 | $320,411 | 0.0% | 1.2% | -19.9% |
| 9 | OLD MISSION CAPITAL LLC | 11,472 | $319,380 | 0.0% | 1.2% | -39.4% |
| 10 | Cambridge Investment Research Advisors, Inc. | 11,385 | $317 | 0.0% | 1.2% | 0.0% |
| 11 | Capital Analysts, LLC | 11,151 | $310 | 0.0% | 1.2% | 0.0% |
| 12 | FIDUCIARY FINANCIAL ADVISORSNEW | 11,049 | $307,604 | 0.0% | 1.2% | new |
| 13 | Sloy Dahl & Holst, LLC | 10,740 | $299,002 | 0.0% | 1.1% | 0.0% |
| 14 | Security Financial Services, INC. | 10,132 | $282,075 | 0.0% | 1.1% | 0.0% |
| 15 | Spire Wealth Management | 2,401 | $66,844 | 0.0% | 0.3% | 0.0% |
| 16 | OSAIC HOLDINGS, INC. | 2,046 | $56,960 | 0.0% | 0.2% | 0.0% |
| 17 | MORGAN STANLEY | 2,000 | $55,680 | 0.0% | 0.2% | 0.0% |
| 18 | TUCKER ASSET MANAGEMENT LLCNEW | 1,782 | $49,611 | 0.0% | 0.2% | new |
| 19 | Regatta Research & Money ManagementNEW | 1,076 | $29,956 | 0.0% | 0.1% | new |
| 20 | CREATIVE FINANCIAL DESIGNS INC /ADV | 492 | $13,697 | 0.0% | 0.1% | -43.5% |
| 21 | New England Capital Financial Advisors LLC | 408 | $11,359 | 0.0% | 0% | 0.0% |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.