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 |
AMC Entertainment Holdings
AMC
|
+$39.3M |
| 2 |
AT&T
T
|
+$29.8M |
| 3 |
NVIDIA
NVDA
|
+$28.3M |
| 4 |
Micron Technology
MU
|
+$22.9M |
| 5 |
Baidu
BIDU
|
+$22.3M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Invesco QQQ Trust
QQQ
|
+$36.1M |
| 2 |
Tesla
TSLA
|
+$35.2M |
| 3 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$25.9M |
| 4 |
Palantir
PLTR
|
+$25.7M |
| 5 |
Wells Fargo
WFC
|
+$20.4M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 97.7% |
| 2 | Technology | 0.48% |
| 3 | Consumer Discretionary | 0.39% |
| 4 | Communication Services | 0.28% |
| 5 | Healthcare | 0.27% |
Similar funds
Simplex Trading's Q2 2021 Portfolio in Review
As of Q2 2021, Simplex Trading held 11,184 positions worth $104B, up 86% from $55.7B the previous quarter. Its ten largest holdings account for 40% of the portfolio.
Simplex Trading's Q2 2021 filing shows 2,248 new, 6,668 increased, 1,000 reduced and 1,196 closed positions. Its largest new stake was AT&T: 1,311,180 shares worth $28.5M. The largest sale was Invesco QQQ Trust, an estimated $36.1M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, up from 97% a quarter earlier, followed by Technology and Consumer Discretionary.
- Simplex Trading's largest Q2 2021 buy was AT&T: 1,311,180 shares worth $28.5M.
- Simplex Trading added most to AMC Entertainment Holdings in Q2 2021, an estimated $39.3M increase.
- Simplex Trading's biggest Q2 2021 reduction was State Street SPDR Dow Jones Industrial Average ETF Trust, cutting an estimated $25.9M.
- Simplex Trading fully exited Invesco QQQ Trust in Q2 2021, selling an estimated $36.1M.
- Simplex Trading's ten largest holdings make up 40% of its $104B portfolio in Q2 2021.
- Simplex Trading opened 2,248 new positions and closed 1,196 in Q2 2021.
- Simplex Trading's portfolio value rose 86% quarter-over-quarter to $104B.
Based on Simplex Trading's 13F filing for Q2 2021, filed 12 Aug 2021.