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 | Technology | 0.59% |
| 2 | Consumer Discretionary | 0.21% |
| 3 | Healthcare | 0.2% |
| 4 | Industrials | 0.18% |
| 5 | Communication Services | 0.16% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
6151
PUT
Ducommun
DCO
$2.7B
| $28.5K | ﹤0.01% |
300
-100
| -25% | -$9.31K |
|
|
ALMU
6152
Aeluma Inc
ALMU
$297M
| $28.5K | ﹤0.01% |
1,658
-1,553
| -48% | -$24.5K |
|
6153
PUT
National Vision
EYE
$1.77B
| $28.4K | ﹤0.01% |
1,100
-800
| -42% | -$21.5K |
|
6154
CALL
Eledon Pharmaceuticals
ELDN
$261M
| $28.4K | ﹤0.01% |
18,800
+12,600
| +203% | +$29.9K |
|
6155
CALL
Ryman Hospitality Properties
RHP
$8.43B
| $28.4K | ﹤0.01% |
300
| – | – |
|
6156
CALL
Evolution Petroleum
EPM
$132M
| $28.3K | ﹤0.01% |
8,000
+3,200
| +67% | +$13.5K |
|
6157
PUT
NET Power
NPWR
$126M
| $28.3K | ﹤0.01% |
12,400
-4,900
| -28% | -$15.3K |
|
6158
PUT
Silgan Holdings
SLGN
$4.23B
| $28.3K | ﹤0.01% |
700
+200
| +40% | +$8.12K |
|
6159
iShares MSCI ACWI ex US ETF
ACWX
$11.5B
| $28.2K | ﹤0.01% |
+420
| New | +$27.8K |
|
6160
Cheniere Energy
CQP
$31.9B
| $28.2K | ﹤0.01% |
527
-1,074
| -67% | -$57K |
|
|
OGI
6161
Organigram Holdings
OGI
$132M
| $28.1K | ﹤0.01% |
+16,739
| New | +$28.8K |
|
6162
Apple Hospitality REIT
APLE
$3.9B
| $28.1K | ﹤0.01% |
2,369
-42,942
| -95% | -$504K |
|
6163
iShares US Healthcare ETF
IYH
$3.37B
| $28.1K | ﹤0.01% |
+431
| New | +$27.2K |
|
6164
PUT
The Greenbrier Companies
GBX
$1.52B
| $28K | ﹤0.01% |
600
-1,100
| -65% | -$49.3K |
|
6165
HUB Group
HUBG
$2.85B
| $28K | ﹤0.01% |
658
-3,360
| -84% | -$128K |
|
6166
Traeger
COOK
$178M
| $28K | ﹤0.01% |
519
+320
| +161% | +$15.6K |
|
6167
CALL
Upland Software
UPLD
$12.8M
| $28K | ﹤0.01% |
1,960
-2,190
| -53% | -$41.7K |
|
|
LOVE
6168
CALL
DELISTED
LoveSac
LOVE
| $28K | ﹤0.01% |
1,900
+1,500
| +375% | +$21.2K |
|
6169
Cheniere Energy
LNG
$55.2B
| $28K | ﹤0.01% |
144
-5,873
| -98% | -$1.23M |
|
6170
CALL
CVR Energy
CVI
$3.58B
| $28K | ﹤0.01% |
1,100
-22,100
| -95% | -$752K |
|
6171
CALL
Fidelity National Financial
FNF
$13.9B
| $28K | ﹤0.01% |
1,100
-22,600
| -95% | -$1.29M |
|
6172
Ameriprise Financial
AMP
$48.3B
| $27.9K | ﹤0.01% |
57
-603
| -91% | -$286K |
|
6173
PUT
Ocugen
OCGN
$416M
| $27.9K | ﹤0.01% |
20,700
+4,800
| +30% | +$6.83K |
|
6174
A10 Networks
ATEN
$2.13B
| $27.9K | ﹤0.01% |
+1,576
| New | +$27.9K |
|
|
AIRO
6175
PUT
AIRO Group Holdings
AIRO
$212M
| $27.8K | ﹤0.01% |
3,400
-12,500
| -79% | -$161K |
|
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 withdrew a net $23.2B in Q4 2025, closing 2,184 positions and reducing 4,088 holdings. Its most notable exit was iShares Russell 2000 ETF, an estimated $149M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.59% of assets, down from 0.79% a quarter earlier, followed by Consumer Discretionary and Healthcare.
Against the trend, Simplex Trading opened a new position in Western Digital worth $58.9M.
- 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.