Simplex Trading Portfolio holdings
Simplex Trading, founded in 2004 and headquartered in Chicago, Illinois, is a technology-driven proprietary trading firm specializing in market-making and liquidity provision, primarily in U.S. equity options and futures options. Leveraging advanced proprietary software and data-driven analysis, the firm optimizes trading strategies and develops innovative solutions to capitalize on financial market opportunities, maintaining a competitive edge through automation and a collaborative team of technologists and traders. With a workforce exceeding 300 and led by CEO Erik Swanson since 2014, Simplex operates with a low-ego, high-intelligence culture, focusing on minimal bureaucracy and rapid execution, while also making strategic venture capital investments in fintech startups. Recognized as a top workplace in Chicago by Built In’s 2025 awards, Simplex continues to evolve, blending cutting-edge technology with a commitment to market efficiency and growth.
Top Buys
| Rank | Stock | Value |
|---|---|---|
| 1 |
NVIDIA
NVDA
|
+$172M |
| 2 |
Apple
AAPL
|
+$156M |
| 3 |
Broadcom
AVGO
|
+$101M |
| 4 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$57.2M |
| 5 |
UnitedHealth
UNH
|
+$55.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$140M |
| 2 |
Amazon
AMZN
|
+$47.9M |
| 3 |
Netflix
NFLX
|
+$38.3M |
| 4 |
TSMC
TSM
|
+$37.3M |
| 5 |
Pfizer
PFE
|
+$36.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.74% |
| 2 | Communication Services | 0.19% |
| 3 | Consumer Discretionary | 0.18% |
| 4 | Healthcare | 0.17% |
| 5 | Financials | 0.14% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
6976
CALL
Neuronetics
STIM
$130M
| $16K | ﹤0.01% |
4,800
-1,000
| -17% | -$3.95K |
|
6977
PUT
Protara Therapeutics
TARA
$221M
| $16K | ﹤0.01% |
5,500
+900
| +20% | +$3.1K |
|
6978
CALL
Mammoth Energy Services
TUSK
$125M
| $16K | ﹤0.01% |
+5,800
| New | +$14.8K |
|
6979
Varex Imaging
VREX
$469M
| $16K | ﹤0.01% |
1,917
+1,786
| +1,363% | +$14.6K |
|
6980
VTEX
VTEX
$745M
| $16K | ﹤0.01% |
2,564
-617
| -19% | -$3.63K |
|
6981
Global X S&P 500 Covered Call ETF
XYLD
$3.21B
| $16K | ﹤0.01% |
436
+374
| +603% | +$14.3K |
|
|
QQQP
6982
Tradr 2X Long Innovation 100 Quarterly ETF
QQQP
$17M
| $16K | ﹤0.01% |
111
-809
| -88% | -$98.9K |
|
|
ROI
6983
PUT
DELISTED
WISDOMTREE LARGECAP GROWTH FUND
ROI
| $16K | ﹤0.01% |
+300
| New | +$16K |
|
|
AIV
6984
PUT
Aimco
AIV
$375M
| $15K | ﹤0.01% |
+1,800
| New | +$14.6K |
|
6985
PUT
ATS Corp
ATS
$2.62B
| $15K | ﹤0.01% |
+500
| New | +$13.7K |
|
|
BLD
6986
DELISTED
TopBuild
BLD
| $15K | ﹤0.01% |
47
-187
| -80% | -$55.5K |
|
6987
CALL
Bank of Marin Bancorp
BMRC
$471M
| $15K | ﹤0.01% |
700
| – | – |
|
6988
PUT
Boston Omaha
BOC
$435M
| $15K | ﹤0.01% |
+1,100
| New | +$16K |
|
6989
PUT
BRC Inc
BRCC
$118M
| $15K | ﹤0.01% |
11,900
+1,300
| +12% | +$2.4K |
|
6990
AGF US Market Neutral Anti-Beta Fund
BTAL
$307M
| $15K | ﹤0.01% |
+898
| New | +$17.5K |
|
6991
Broadwind
BWEN
$92.9M
| $15K | ﹤0.01% |
8,498
+3,692
| +77% | +$6.23K |
|
6992
CALL
China Automotive Systems
CAAS
$131M
| $15K | ﹤0.01% |
3,700
-400
| -10% | -$1.61K |
|
|
CCC
6993
CALL
CCC Intelligent Solutions
CCC
$3.59B
| $15K | ﹤0.01% |
1,700
-6,300
| -79% | -$56.4K |
|
|
CEPU
6994
Central Puerto
CEPU
$2.18B
| $15K | ﹤0.01% |
1,296
-387
| -23% | -$4.56K |
|
6995
CALL
Traeger
COOK
$164M
| $15K | ﹤0.01% |
186
-20
| -10% | -$1.54K |
|
6996
CALL
Cemex
CX
$17.3B
| $15K | ﹤0.01% |
2,200
-31,000
| -93% | -$197K |
|
6997
CALL
Daktronics
DAKT
$953M
| $15K | ﹤0.01% |
1,000
-22,300
| -96% | -$307K |
|
6998
Strive US Energy ETF
DRLL
$286M
| $15K | ﹤0.01% |
+557
| New | +$14.8K |
|
6999
PUT
Enovis
ENOV
$1.7B
| $15K | ﹤0.01% |
500
| – | – |
|
7000
Erie Indemnity
ERIE
$12.7B
| $15K | ﹤0.01% |
+45
| New | +$16.7K |
|
Similar funds
Simplex Trading's Q2 2025 Portfolio in Review
As of Q2 2025, Simplex Trading held 10,048 positions worth $175B, up 12% from $156B the previous quarter. Its ten largest holdings account for 47% of the portfolio.
Simplex Trading withdrew a net $10.5B in Q2 2025, closing 1,431 positions and reducing 3,590 holdings. Its most notable exit was Constellation Energy, an estimated $35.8M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.74% of assets, up from 0.41% a quarter earlier, followed by Communication Services and Consumer Discretionary.
Against the trend, Simplex Trading opened a new position in State Street SPDR S&P 500 ETF Trust worth $61.9M.
- Simplex Trading's largest Q2 2025 buy was State Street SPDR S&P 500 ETF Trust: 100,129 shares worth $61.9M.
- Simplex Trading added most to NVIDIA in Q2 2025, an estimated $172M increase.
- Simplex Trading's biggest Q2 2025 reduction was iShares 20+ Year Treasury Bond ETF, cutting an estimated $140M.
- Simplex Trading fully exited Constellation Energy in Q2 2025, selling an estimated $35.8M.
- Simplex Trading's ten largest holdings make up 47% of its $175B portfolio in Q2 2025.
- Simplex Trading opened 1,525 new positions and closed 1,431 in Q2 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $175B.
Based on Simplex Trading's 13F filing for Q2 2025, filed 5 Aug 2025.