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 |
Amazon
AMZN
|
+$148M |
| 2 |
Invesco QQQ Trust
QQQ
|
+$67.3M |
| 3 |
Meta Platforms (Facebook)
META
|
+$63.2M |
| 4 |
Goldman Sachs
GS
|
+$23.9M |
| 5 |
Citigroup
C
|
+$23.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Berkshire Hathaway Class B
BRK.B
|
+$47.5M |
| 2 |
Apple
AAPL
|
+$46M |
| 3 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$44.5M |
| 4 |
Micron Technology
MU
|
+$29.1M |
| 5 |
Adobe
ADBE
|
+$22.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 95.2% |
| 2 | Consumer Discretionary | 1.14% |
| 3 | Communication Services | 0.9% |
| 4 | Technology | 0.69% |
| 5 | Industrials | 0.52% |
Similar funds
Simplex Trading's Q3 2018 Portfolio in Review
As of Q3 2018, Simplex Trading held 8,699 positions worth $31.1B, up 22% from $25.5B the previous quarter. Its ten largest holdings account for 34% of the portfolio.
Simplex Trading's Q3 2018 filing shows 1,336 new, 3,066 increased, 2,754 reduced and 1,316 closed positions. Its largest new stake was Invesco QQQ Trust: 371,806 shares worth $69.1M. The largest sale was Berkshire Hathaway Class B, an estimated $47.5M.
By sector, the portfolio is most concentrated in Miscellaneous at 95% of assets, up from 94% a quarter earlier, followed by Consumer Discretionary and Communication Services.
- Simplex Trading's largest Q3 2018 buy was Invesco QQQ Trust: 371,806 shares worth $69.1M.
- Simplex Trading added most to Amazon in Q3 2018, an estimated $148M increase.
- Simplex Trading's biggest Q3 2018 reduction was Apple, cutting an estimated $46M.
- Simplex Trading fully exited Berkshire Hathaway Class B in Q3 2018, selling an estimated $47.5M.
- Simplex Trading's ten largest holdings make up 34% of its $31.1B portfolio in Q3 2018.
- Simplex Trading opened 1,336 new positions and closed 1,316 in Q3 2018.
- Simplex Trading's portfolio value rose 22% quarter-over-quarter to $31.1B.
Based on Simplex Trading's 13F filing for Q3 2018, filed 23 Oct 2018.