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 |
Invesco QQQ Trust
QQQ
|
+$86.9M |
| 2 |
Walt Disney
DIS
|
+$25.5M |
| 3 |
Baidu
BIDU
|
+$12.3M |
| 4 |
Alphabet (Google) Class A
GOOGL
|
+$12.3M |
| 5 |
RHT
Red Hat Inc
RHT
|
+$11.4M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Amazon
AMZN
|
+$66M |
| 2 |
iShares Russell 2000 ETF
IWM
|
+$60.3M |
| 3 |
Alphabet (Google) Class C
GOOG
|
+$33.9M |
| 4 |
Apple
AAPL
|
+$21.1M |
| 5 |
State Street Financial Select Sector SPDR ETF
XLF
|
+$18.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 97.42% |
| 2 | Communication Services | 0.59% |
| 3 | Technology | 0.46% |
| 4 | Healthcare | 0.38% |
| 5 | Consumer Discretionary | 0.29% |
Similar funds
Simplex Trading's Q1 2019 Portfolio in Review
As of Q1 2019, Simplex Trading held 8,479 positions worth $36B, up 5.5% from $34.1B the previous quarter. Its ten largest holdings account for 35% of the portfolio.
Simplex Trading's Q1 2019 filing shows 1,471 new, 3,049 increased, 2,419 reduced and 1,324 closed positions. Its largest new stake was Walt Disney: 228,471 shares worth $25.4M. The largest sale was Amazon, an estimated $66M.
By sector, the portfolio is most concentrated in Miscellaneous at 97% of assets, down from 97% a quarter earlier, followed by Communication Services and Technology.
- Simplex Trading's largest Q1 2019 buy was Walt Disney: 228,471 shares worth $25.4M.
- Simplex Trading added most to Invesco QQQ Trust in Q1 2019, an estimated $86.9M increase.
- Simplex Trading's biggest Q1 2019 reduction was iShares Russell 2000 ETF, cutting an estimated $60.3M.
- Simplex Trading fully exited Amazon in Q1 2019, selling an estimated $66M.
- Simplex Trading's ten largest holdings make up 35% of its $36B portfolio in Q1 2019.
- Simplex Trading opened 1,471 new positions and closed 1,324 in Q1 2019.
- Simplex Trading's portfolio value rose 5.5% quarter-over-quarter to $36B.
Based on Simplex Trading's 13F filing for Q1 2019, filed 18 Apr 2019.