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 | |
|---|---|---|---|---|---|---|
6101
Suburban Propane Partners
SPH
$1.24B
| $30.2K | ﹤0.01% |
1,630
-645
| -28% | -$12.1K |
|
|
BNCWW
6102
PUT
CEA Industries Inc Warrant
BNCWW
| $30.2K | ﹤0.01% |
4,700
-32,900
| -88% | -$3.71K |
|
|
GAU
6103
PUT
Galiano Gold
GAU
$455M
| $30.1K | ﹤0.01% |
11,900
-12,500
| -51% | -$30.9K |
|
6104
PUT
SEACOR Marine Holdings
SMHI
$256M
| $30.1K | ﹤0.01% |
5,000
| – | – |
|
|
PINE
6105
PUT
Alpine Income Property Trust
PINE
$333M
| $30.1K | ﹤0.01% |
1,800
+100
| +6% | +$1.56K |
|
6106
Essex Property Trust
ESS
$18.3B
| $30.1K | ﹤0.01% |
+115
| New | +$29.8K |
|
6107
PUT
iPath Bloomberg Commodity Index Total Return ETN due 12 June 2036
DJP
$800M
| $30.1K | ﹤0.01% |
+800
| New | +$29.5K |
|
6108
Appian
APPN
$1.98B
| $30.1K | ﹤0.01% |
849
-20,570
| -96% | -$733K |
|
|
OLPX
6109
DELISTED
Olaplex Holdings
OLPX
| $30.1K | ﹤0.01% |
+22,439
| New | +$26.7K |
|
|
AUTL
6110
CALL
Autolus Therapeutics
AUTL
$397M
| $30K | ﹤0.01% |
15,100
-12,000
| -44% | -$18.4K |
|
6111
PUT
Sanmina
SANM
$9.95B
| $30K | ﹤0.01% |
200
-50,400
| -100% | -$7.44M |
|
6112
PUT
Rollins
ROL
$18.3B
| $30K | ﹤0.01% |
500
-800
| -62% | -$47K |
|
6113
CALL
Innoviva
INVA
$1.55B
| $30K | ﹤0.01% |
+1,500
| New | +$29.3K |
|
6114
Flotek Industries
FTK
$852M
| $30K | ﹤0.01% |
1,739
-10,620
| -86% | -$169K |
|
6115
PUT
Suzano
SUZ
$10.5B
| $29.9K | ﹤0.01% |
3,200
-300
| -9% | -$2.73K |
|
6116
CALL
Savers
SVV
$1.58B
| $29.9K | ﹤0.01% |
3,200
-35,200
| -92% | -$362K |
|
|
NVNO
6117
enVVeno Medical
NVNO
$7.08M
| $29.9K | ﹤0.01% |
2,659
+2,266
| +577% | +$44K |
|
6118
CALL
Expeditors International
EXPD
$22B
| $29.8K | ﹤0.01% |
200
-5,700
| -97% | -$776K |
|
6119
PUT
Voya Financial
VOYA
$9.01B
| $29.8K | ﹤0.01% |
400
-20,500
| -98% | -$1.49M |
|
6120
Ardagh Metal Packaging
AMBP
$2.83B
| $29.8K | ﹤0.01% |
7,261
-26,320
| -78% | -$99.8K |
|
6121
Richardson Electronics
RELL
$267M
| $29.7K | ﹤0.01% |
+2,728
| New | +$29.1K |
|
|
BRSP
6122
PUT
BrightSpire Capital
BRSP
$634M
| $29.7K | ﹤0.01% |
5,300
| – | – |
|
6123
CALL
Star Holdings Shares of Beneficial Interest
STHO
$113M
| $29.6K | ﹤0.01% |
3,600
+1,200
| +50% | +$9.19K |
|
|
TMHC
6124
CALL
DELISTED
Taylor Morrison
TMHC
| $29.4K | ﹤0.01% |
500
-500
| -50% | -$30.6K |
|
6125
PUT
STAG Industrial
STAG
$7.38B
| $29.4K | ﹤0.01% |
800
-2,200
| -73% | -$83.5K |
|
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.