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 | |
|---|---|---|---|---|---|---|
|
CFLT
1501
PUT
DELISTED
Confluent
CFLT
| $4.15M | ﹤0.01% |
166,400
-43,600
| -21% | -$983K |
|
1502
PUT
Knight Transportation
KNX
$11.8B
| $4.13M | ﹤0.01% |
93,500
+87,300
| +1,408% | +$3.71M |
|
1503
PUT
Emerson Electric
EMR
$82.9B
| $4.13M | ﹤0.01% |
31,000
-12,700
| -29% | -$1.46M |
|
1504
PUT
BridgeBio Pharma
BBIO
$16.5B
| $4.13M | ﹤0.01% |
95,700
+24,800
| +35% | +$902K |
|
1505
PUT
SLM Corp
SLM
$4.58B
| $4.13M | ﹤0.01% |
126,000
-200
| -0.2% | -$6.12K |
|
1506
Eli Lilly
LLY
$1.07T
| $4.12M | ﹤0.01% |
+5,286
| New | +$4.11M |
|
1507
CALL
Vail Resorts
MTN
$5.19B
| $4.12M | ﹤0.01% |
26,200
-11,400
| -30% | -$1.69M |
|
|
GPGI
1508
PUT
GPGI Inc
GPGI
$4.06B
| $4.11M | ﹤0.01% |
292,000
+219,600
| +303% | +$2.69M |
|
1509
Home Depot
HD
$332B
| $4.11M | ﹤0.01% |
11,202
-20,344
| -64% | -$7.36M |
|
1510
CALL
Ultragenyx Pharmaceutical
RARE
$2.65B
| $4.11M | ﹤0.01% |
112,900
+66,700
| +144% | +$2.4M |
|
1511
CALL
STMicroelectronics
STM
$46B
| $4.11M | ﹤0.01% |
135,000
-62,700
| -32% | -$1.56M |
|
1512
CALL
Dave & Buster's
PLAY
$343M
| $4.1M | ﹤0.01% |
136,400
-8,000
| -6% | -$181K |
|
1513
PUT
ResMed
RMD
$28.3B
| $4.1M | ﹤0.01% |
15,900
-77,600
| -83% | -$18.5M |
|
1514
CALL
FirstEnergy
FE
$28.9B
| $4.1M | ﹤0.01% |
101,800
-252,100
| -71% | -$10.4M |
|
1515
Flex
FLEX
$43.4B
| $4.09M | ﹤0.01% |
82,051
+79,725
| +3,428% | +$3.11M |
|
1516
PUT
Monolithic Power Systems
MPWR
$65.5B
| $4.09M | ﹤0.01% |
5,600
-1,900
| -25% | -$1.21M |
|
1517
CALL
Applied Optoelectronics
AAOI
$8.04B
| $4.09M | ﹤0.01% |
159,400
-15,500
| -9% | -$251K |
|
1518
CALL
United Therapeutics
UTHR
$26.3B
| $4.08M | ﹤0.01% |
14,200
+10,100
| +246% | +$3.02M |
|
1519
PUT
Brinker International
EAT
$8.02B
| $4.08M | ﹤0.01% |
22,600
-64,500
| -74% | -$10.1M |
|
1520
Ford
F
$57.3B
| $4.07M | ﹤0.01% |
375,382
-848,218
| -69% | -$8.64M |
|
1521
CALL
Williams-Sonoma
WSM
$26.7B
| $4.07M | ﹤0.01% |
24,900
-36,800
| -60% | -$5.78M |
|
1522
CALL
Stem
STEM
$49.2M
| $4.06M | ﹤0.01% |
651,900
+620,880
| +2,002% | +$5.57M |
|
|
TGNA
1523
PUT
DELISTED
TEGNA Inc
TGNA
| $4.06M | ﹤0.01% |
242,200
+1,100
| +0.5% | +$18.3K |
|
|
CIVI
1524
CALL
DELISTED
Civitas Resources
CIVI
| $4.06M | ﹤0.01% |
147,400
+95,300
| +183% | +$2.76M |
|
1525
PUT
Viasat
VSAT
$9.79B
| $4.05M | ﹤0.01% |
277,300
+84,000
| +43% | +$850K |
|
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.