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 |
iShares Russell 2000 ETF
IWM
|
+$58.5M |
| 2 |
Alphabet (Google) Class C
GOOG
|
+$56.5M |
| 3 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$44.1M |
| 4 |
Apple
AAPL
|
+$20.3M |
| 5 |
State Street SPDR S&P Oil & Gas Exploration & Production ETF
XOP
|
+$12.7M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Amazon
AMZN
|
+$109M |
| 2 |
Meta Platforms (Facebook)
META
|
+$62.3M |
| 3 |
Invesco QQQ Trust
QQQ
|
+$36.2M |
| 4 |
Goldman Sachs
GS
|
+$27.1M |
| 5 |
Boeing
BA
|
+$24.7M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Communication Services | 0.49% |
| 2 | Consumer Discretionary | 0.48% |
| 3 | Technology | 0.4% |
| 4 | Financials | 0.25% |
| 5 | Industrials | 0.22% |
Similar funds
Simplex Trading's Q4 2018 Portfolio in Review
As of Q4 2018, Simplex Trading held 8,576 positions worth $34.1B, up 9.5% from $31.1B the previous quarter. Its ten largest holdings account for 43% of the portfolio.
Simplex Trading's Q4 2018 filing shows 1,199 new, 2,701 increased, 2,877 reduced and 1,573 closed positions. Its largest new stake was State Street SPDR S&P 500 ETF Trust: 163,699 shares worth $40.9M. The largest sale was Amazon, an estimated $109M.
By sector, the portfolio is most concentrated in Communication Services at 0.49% of assets, down from 0.89% a quarter earlier, followed by Consumer Discretionary and Technology.
- Simplex Trading's largest Q4 2018 buy was State Street SPDR S&P 500 ETF Trust: 163,699 shares worth $40.9M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q4 2018, an estimated $58.5M increase.
- Simplex Trading's biggest Q4 2018 reduction was Amazon, cutting an estimated $109M.
- Simplex Trading fully exited Meta Platforms (Facebook) in Q4 2018, selling an estimated $62.3M.
- Simplex Trading's ten largest holdings make up 43% of its $34.1B portfolio in Q4 2018.
- Simplex Trading opened 1,199 new positions and closed 1,573 in Q4 2018.
- Simplex Trading's portfolio value rose 9.5% quarter-over-quarter to $34.1B.
Based on Simplex Trading's 13F filing for Q4 2018, filed 16 Jan 2019.