Calamos S&P 500 Structured Alt Protection ETF - September
CPST
17 hedge funds and large institutions have $15.1M invested in Calamos S&P 500 Structured Alt Protection ETF - September in 2025 Q3 according to their latest regulatory filings, with 5 funds opening new positions, 3 increasing their positions, 5 reducing their positions, and 2 closing their positions.
150% more first-time investments, than exits
New positions opened: 5 | Existing positions closed: 2
21% more funds holding
Funds holding: 14 → 17 (+3)
12% more capital invested
Capital invested by funds: $13.5M → $15.1M (+$1.61M)
0.27% less ownership
Funds ownership: 51.7% → 51.43% (-0.27%)
40% less repeat investments, than reductions
Existing positions increased: 3 | Existing positions reduced: 5
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
HI
Harbour Investments
Madison,
Wisconsin
|
+$410K |
| 2 |
Jane Street
New York
|
+$340K |
| 3 |
GFG
Grantvest Financial Group
Matawan,
New Jersey
|
+$323K |
| 4 |
PCA
Pallas Capital Advisors
Braintree,
Massachusetts
|
+$252K |
| 5 |
CWM
Calamos Wealth Management
Naperville,
Illinois
|
+$223K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
MOS
MGO One Seven
Beachwood,
Ohio
|
-$235K |
| 2 |
OMC
Old Mission Capital
Chicago,
Illinois
|
-$126K |
| 3 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
-$57.3K |
| 4 |
Calamos Advisors
Naperville,
Illinois
|
-$55.6K |
| 5 |
CAL
Capital Analysts LLC
Fort Washington,
Pennsylvania
|
-$23.3K |
CPST Hedge Fund Activity: Q3 2025 in Review
17 of the 7,621 institutional investors tracked by Wall St. Rank reported a position in Calamos S&P 500 Structured Alt Protection ETF - September (CPST) for Q3 2025, worth a combined $15.1M — up 12% from $13.5M a quarter earlier.
Buyers outnumbered sellers: 5 funds opened new CPST positions and 2 closed out — a net gain of 3 holders — while 3 added to existing stakes and 5 trimmed.
The largest buyer was Harbour Investments, opening a new position worth an estimated $410K. The largest seller was MGO One Seven, exiting entirely with an estimated $235K sold.
- 17 institutional investors held Calamos S&P 500 Structured Alt Protection ETF - September (CPST) as of Q3 2025, up from 14 in Q2 2025.
- Funds reported $15.1M of Calamos S&P 500 Structured Alt Protection ETF - September stock for Q3 2025, up 12% quarter-over-quarter.
- 5 funds opened new Calamos S&P 500 Structured Alt Protection ETF - September positions in Q3 2025 and 2 closed out, a net change of +3 holders.
- The largest Calamos S&P 500 Structured Alt Protection ETF - September buyer in Q3 2025 was Harbour Investments, an estimated $410K added.
- The largest Calamos S&P 500 Structured Alt Protection ETF - September seller in Q3 2025 was MGO One Seven, an estimated $235K sold.
Based on aggregated 13F filings for Q3 2025.