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 | |
|---|---|---|---|---|---|---|
6776
Quanterix
QTRX
$164M
| $20K | ﹤0.01% |
+3,152
| New | +$17.6K |
|
|
RGLS
6777
PUT
DELISTED
Regulus Therapeutics
RGLS
| $20K | ﹤0.01% |
97,700
+91,500
| +1,476% | +$546K |
|
6778
First Trust Nasdaq Artificial Intelligence and Robotics ETF
ROBT
$707M
| $20K | ﹤0.01% |
+419
| New | +$18.1K |
|
6779
CALL
Rogers Corp
ROG
$2.13B
| $20K | ﹤0.01% |
300
-100
| -25% | -$6.45K |
|
6780
PUT
Shenandoah Telecom
SHEN
$655M
| $20K | ﹤0.01% |
1,500
| – | – |
|
6781
PUT
Sylvamo
SLVM
$1.55B
| $20K | ﹤0.01% |
+400
| New | +$22.5K |
|
6782
StepStone Group
STEP
$3.65B
| $20K | ﹤0.01% |
+372
| New | +$19.9K |
|
6783
Cambria Tail Risk ETF
TAIL
$149M
| $20K | ﹤0.01% |
+1,742
| New | +$21.7K |
|
6784
Tootsie Roll Industries
TR
$2.94B
| $20K | ﹤0.01% |
621
-642
| -51% | -$20.6K |
|
6785
PUT
Thomson Reuters
TRI
$45.1B
| $20K | ﹤0.01% |
+98
| New | +$18.7K |
|
|
TSE
6786
CALL
DELISTED
Trinseo
TSE
| $20K | ﹤0.01% |
6,500
-11,300
| -63% | -$37.2K |
|
6787
Vera Bradley
VRA
$104M
| $20K | ﹤0.01% |
9,138
+6,941
| +316% | +$14.3K |
|
6788
PUT
Wabtec
WAB
$51.7B
| $20K | ﹤0.01% |
+100
| New | +$19.2K |
|
6789
CALL
Worthington Steel
WS
$1.9B
| $20K | ﹤0.01% |
+700
| New | +$18K |
|
6790
PUT
Arq
ARQ
$83.7M
| $20K | ﹤0.01% |
3,800
-7,300
| -66% | -$31.9K |
|
|
AAT
6791
PUT
American Assets Trust
AAT
$1.48B
| $19K | ﹤0.01% |
1,000
+900
| +900% | +$17.5K |
|
6792
CALL
ADC Therapeutics
ADCT
$141M
| $19K | ﹤0.01% |
+7,100
| New | +$14.9K |
|
|
6793
ADC Therapeutics
ADCT
$141M
| $19K | ﹤0.01% |
+7,350
| New | +$15.5K |
|
6794
Allogene Therapeutics
ALLO
$573M
| $19K | ﹤0.01% |
17,029
-642
| -4% | -$853 |
|
6795
Direxion Daily AMZN Bull 2X ETF
AMZU
$268M
| $19K | ﹤0.01% |
540
-10,663
| -95% | -$329K |
|
6796
Atlas Lithium Corp
ATLX
$79.3M
| $19K | ﹤0.01% |
5,036
+3,088
| +159% | +$12.9K |
|
6797
CALL
Avalo Therapeutics
AVTX
$1.03B
| $19K | ﹤0.01% |
+4,000
| New | +$18.7K |
|
6798
PUT
BOK Financial
BOKF
$8.65B
| $19K | ﹤0.01% |
200
-100
| -33% | -$9.41K |
|
6799
Corbus Pharmaceuticals
CRBP
$168M
| $19K | ﹤0.01% |
2,819
-3,054
| -52% | -$22.2K |
|
|
HELP
6800
PUT
Cybin Inc
HELP
$471M
| $19K | ﹤0.01% |
2,300
-1,700
| -43% | -$12.4K |
|
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.