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 |
Netflix
NFLX
|
+$73.1M |
| 2 |
Western Digital
WDC
|
+$51.8M |
| 3 |
iShares Semiconductor ETF
SOXX
|
+$46M |
| 4 |
Meta Platforms (Facebook)
META
|
+$41.8M |
| 5 |
Alibaba
BABA
|
+$37.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
NVIDIA
NVDA
|
+$262M |
| 2 |
Microsoft
MSFT
|
+$194M |
| 3 |
iShares Russell 2000 ETF
IWM
|
+$149M |
| 4 |
Apple
AAPL
|
+$119M |
| 5 |
Amazon
AMZN
|
+$107M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 98.27% |
| 2 | Technology | 0.59% |
| 3 | Consumer Discretionary | 0.21% |
| 4 | Healthcare | 0.2% |
| 5 | Industrials | 0.18% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
|
CRCL
176
CALL
Circle Internet Group
CRCL
$25.9B
| $87.9M | 0.05% |
1,108,500
+176,200
| +19% | +$18.2M |
|
177
CALL
Wells Fargo
WFC
$272B
| $87.4M | 0.05% |
938,200
-324,000
| -26% | -$28.1M |
|
178
PUT
Chevron
CVX
$409B
| $87.3M | 0.05% |
572,800
+80,000
| +16% | +$12.2M |
|
179
PUT
Super Micro Computer
SMCI
$26B
| $86.7M | 0.05% |
2,962,700
-667,000
| -18% | -$27.5M |
|
180
PUT
American Airlines Group
AAL
$8.69B
| $85.4M | 0.05% |
5,568,300
-105,700
| -2% | -$1.43M |
|
181
CALL
AST SpaceMobile
ASTS
$18.7B
| $85.3M | 0.05% |
1,174,800
+66,200
| +6% | +$4.72M |
|
|
182
CALL
Chevron
CVX
$409B
| $84.3M | 0.05% |
553,000
-21,900
| -4% | -$3.34M |
|
183
PUT
Shopify
SHOP
$187B
| $84M | 0.05% |
522,000
-222,400
| -30% | -$35.7M |
|
184
PUT
Rivian
RIVN
$22.8B
| $83.7M | 0.05% |
4,244,900
+944,700
| +29% | +$15M |
|
185
PUT
ARK Space & Defense Innovation ETF
ARKX
$764M
| $83.6M | 0.05% |
1,210,700
-2,248,500
| -65% | -$65.7M |
|
186
PUT
Constellation Energy
CEG
$106B
| $82.4M | 0.05% |
233,300
-13,400
| -5% | -$4.87M |
|
187
CALL
Target
TGT
$74.7B
| $81.6M | 0.05% |
834,600
-449,000
| -35% | -$41.4M |
|
188
CALL
Morgan Stanley
MS
$342B
| $80.6M | 0.05% |
454,000
-262,500
| -37% | -$43.8M |
|
189
PUT
Warner Bros
WBD
$70.8B
| $80.6M | 0.05% |
2,796,000
-153,100
| -5% | -$3.58M |
|
190
Broadcom
AVGO
$1.7T
| $80.4M | 0.05% |
232,173
-49,323
| -18% | -$17.6M |
|
191
CALL
PepsiCo
PEP
$188B
| $79.7M | 0.04% |
555,200
-25,300
| -4% | -$3.72M |
|
192
PUT
Visa
V
$700B
| $78.7M | 0.04% |
224,500
-83,700
| -27% | -$28.5M |
|
193
CALL
GE Vernova
GEV
$251B
| $78.7M | 0.04% |
120,400
+3,800
| +3% | +$2.31M |
|
194
CALL
Airbnb
ABNB
$107B
| $78.5M | 0.04% |
578,500
+93,800
| +19% | +$11.7M |
|
|
195
PUT
PepsiCo
PEP
$188B
| $77.8M | 0.04% |
542,100
-13,500
| -2% | -$1.98M |
|
196
PUT
Merck
MRK
$371B
| $76.8M | 0.04% |
729,600
-299,100
| -29% | -$28.1M |
|
197
CALL
Comcast
CMCSA
$94B
| $76.5M | 0.04% |
2,560,300
+898,600
| +54% | +$25.6M |
|
198
CALL
Carnival Corporation Ltd
CCL
$32.2B
| $76.3M | 0.04% |
2,497,600
-945,800
| -27% | -$26.4M |
|
199
PUT
Home Depot
HD
$320B
| $76M | 0.04% |
220,900
+39,200
| +22% | +$14.4M |
|
200
PUT
Rocket Lab Corp
RKLB
$41.1B
| $75.7M | 0.04% |
1,085,300
+16,200
| +2% | +$929K |
|
Similar funds
Simplex Trading's Q4 2025 Portfolio in Review
As of Q4 2025, Simplex Trading held 10,526 positions worth $177B, down 9% from $195B the previous quarter. Its ten largest holdings account for 49% of the portfolio.
Simplex Trading's Q4 2025 filing shows 1,476 new, 2,599 increased, 4,088 reduced and 2,184 closed positions. Its largest new stake was Western Digital: 341,762 shares worth $58.9M. The largest sale was NVIDIA, an estimated $262M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, up from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- Simplex Trading's largest Q4 2025 buy was Western Digital: 341,762 shares worth $58.9M.
- Simplex Trading added most to Netflix in Q4 2025, an estimated $73.1M increase.
- Simplex Trading's biggest Q4 2025 reduction was NVIDIA, cutting an estimated $262M.
- Simplex Trading fully exited iShares Russell 2000 ETF in Q4 2025, selling an estimated $149M.
- Simplex Trading's ten largest holdings make up 49% of its $177B portfolio in Q4 2025.
- Simplex Trading opened 1,476 new positions and closed 2,184 in Q4 2025.
- Simplex Trading's portfolio value fell 9% quarter-over-quarter to $177B.
Based on Simplex Trading's 13F filing for Q4 2025, filed 11 Feb 2026.