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 | |
|---|---|---|---|---|---|---|
2251
CALL
LSB Industries
LXU
$881M
| $1.44M | ﹤0.01% |
169,800
+132,700
| +358% | +$1.17M |
|
|
PPTA
2252
PUT
Perpetua Resources
PPTA
$2.23B
| $1.44M | ﹤0.01% |
59,500
-192,500
| -76% | -$4.74M |
|
2253
PUT
Trane Technologies
TT
$106B
| $1.44M | ﹤0.01% |
3,700
-1,000
| -21% | -$414K |
|
|
FIGR
2254
CALL
Figure Technology Solutions
FIGR
$6.1B
| $1.44M | ﹤0.01% |
35,200
+20,300
| +136% | +$812K |
|
2255
Wendy's
WEN
$1.33B
| $1.44M | ﹤0.01% |
172,494
-46,644
| -21% | -$402K |
|
2256
PUT
Equinor
EQNR
$95.9B
| $1.44M | ﹤0.01% |
60,800
-10,000
| -14% | -$236K |
|
2257
AXT Inc
AXTI
$3.09B
| $1.43M | ﹤0.01% |
87,693
+61,383
| +233% | +$593K |
|
2258
CALL
American Battery Technology Co
ABAT
$301M
| $1.43M | ﹤0.01% |
429,100
+232,700
| +118% | +$1.09M |
|
2259
PUT
Brighthouse Financial
BHF
$3.63B
| $1.43M | ﹤0.01% |
22,100
-136,400
| -86% | -$8.01M |
|
2260
CALL
Verisk Analytics
VRSK
$26.4B
| $1.43M | ﹤0.01% |
6,400
-500
| -7% | -$113K |
|
2261
CALL
Sonos
SONO
$1.75B
| $1.43M | ﹤0.01% |
81,500
+17,000
| +26% | +$296K |
|
2262
PUT
ADMA Biologics
ADMA
$1.92B
| $1.43M | ﹤0.01% |
78,400
-89,100
| -53% | -$1.5M |
|
2263
PUT
Agilent Technologies
A
$39.1B
| $1.43M | ﹤0.01% |
10,500
+1,200
| +13% | +$172K |
|
2264
CALL
The Oncology Institute
TOI
$498M
| $1.43M | ﹤0.01% |
401,200
-2,000
| -0.5% | -$7.42K |
|
2265
CALL
Biohaven
BHVN
$2.16B
| $1.43M | ﹤0.01% |
126,500
-44,700
| -26% | -$554K |
|
|
TPC
2266
PUT
Tutor Perini Cor
TPC
$4.57B
| $1.43M | ﹤0.01% |
21,300
-12,000
| -36% | -$787K |
|
2267
Energy Fuels
UUUU
$2.82B
| $1.43M | ﹤0.01% |
98,095
-349,830
| -78% | -$5.94M |
|
2268
CALL
Veritone
VERI
$96.7M
| $1.43M | ﹤0.01% |
306,500
+229,000
| +295% | +$1.23M |
|
2269
PUT
Trevi Therapeutics
TRVI
$2.49B
| $1.42M | ﹤0.01% |
113,800
-241,000
| -68% | -$2.79M |
|
2270
Toyota
TM
$210B
| $1.42M | ﹤0.01% |
6,650
+4,933
| +287% | +$1M |
|
2271
PUT
Yum China
YUMC
$14.9B
| $1.42M | ﹤0.01% |
29,800
-41,000
| -58% | -$1.88M |
|
2272
CALL
Semtech
SMTC
$11.7B
| $1.42M | ﹤0.01% |
19,300
+3,500
| +22% | +$248K |
|
2273
PUT
BBVA Argentina
BBAR
$3.85B
| $1.42M | ﹤0.01% |
78,400
+16,600
| +27% | +$238K |
|
2274
PUT
SLM Corp
SLM
$4.57B
| $1.41M | ﹤0.01% |
52,200
-107,800
| -67% | -$2.96M |
|
2275
Palo Alto Networks
PANW
$264B
| $1.41M | ﹤0.01% |
+7,667
| New | +$1.55M |
|
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.