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 | |
|---|---|---|---|---|---|---|
3151
Peloton Interactive
PTON
$2.71B
| $585K | ﹤0.01% |
94,908
-10,399
| -10% | -$73.2K |
|
3152
CALL
Unilever
UL
$132B
| $585K | ﹤0.01% |
73,100
-22,811
| -24% | -$1.53M |
|
3153
PUT
Genworth Financial
GNW
$3.79B
| $582K | ﹤0.01% |
64,500
+48,800
| +311% | +$425K |
|
3154
CALL
Beazer Homes USA
BZH
$903M
| $582K | ﹤0.01% |
28,700
+16,700
| +139% | +$372K |
|
3155
PUT
Forte Biosciences
FBRX
$1.57B
| $581K | ﹤0.01% |
+21,300
| New | +$373K |
|
3156
CALL
ZTO Express
ZTO
$18.1B
| $581K | ﹤0.01% |
27,800
-4,200
| -13% | -$83.2K |
|
3157
CALL
Avantor
AVTR
$8.03B
| $580K | ﹤0.01% |
50,600
-30,800
| -38% | -$379K |
|
3158
PUT
Royalty Pharma
RPRX
$26B
| $580K | ﹤0.01% |
15,000
+9,900
| +194% | +$378K |
|
3159
PUT
Philips
PHG
$24.3B
| $580K | ﹤0.01% |
22,195
-15,245
| -41% | -$407K |
|
|
VNET
3160
PUT
VNET Group
VNET
$2.04B
| $580K | ﹤0.01% |
68,500
+2,100
| +3% | +$19.5K |
|
3161
TripAdvisor
TRIP
$1.66B
| $579K | ﹤0.01% |
39,768
-98,829
| -71% | -$1.5M |
|
3162
Fluence Energy
FLNC
$1.79B
| $578K | ﹤0.01% |
+29,210
| New | +$550K |
|
3163
PUT
Comstock
LODE
$236M
| $577K | ﹤0.01% |
153,400
+124,900
| +438% | +$425K |
|
3164
CALL
Broadstone Net Lease
BNL
$4.29B
| $577K | ﹤0.01% |
33,200
-27,100
| -45% | -$488K |
|
3165
PUT
Dave Inc
DAVE
$5.16B
| $576K | ﹤0.01% |
2,600
-3,400
| -57% | -$731K |
|
3166
H&R Block
HRB
$5.37B
| $575K | ﹤0.01% |
13,203
+11,095
| +526% | +$519K |
|
|
VOYG
3167
CALL
Voyager Technologies
VOYG
$1.56B
| $575K | ﹤0.01% |
22,000
+10,300
| +88% | +$279K |
|
3168
CALL
The Ensign Group
ENSG
$10.4B
| $575K | ﹤0.01% |
3,300
-2,000
| -38% | -$359K |
|
3169
CALL
NiSource
NI
$22B
| $572K | ﹤0.01% |
13,700
-42,700
| -76% | -$1.82M |
|
3170
PUT
Vital Farms
VITL
$569M
| $572K | ﹤0.01% |
17,900
+1,300
| +8% | +$45.8K |
|
3171
Gold Fields
GFI
$29.4B
| $571K | ﹤0.01% |
+13,076
| New | +$546K |
|
3172
CALL
Installed Building Products
IBP
$6.16B
| $571K | ﹤0.01% |
2,200
+600
| +38% | +$155K |
|
3173
Canadian Natural Resources
CNQ
$93.4B
| $570K | ﹤0.01% |
16,825
+1,347
| +9% | +$43.7K |
|
|
JKS
3174
CALL
JinkoSolar
JKS
$799M
| $568K | ﹤0.01% |
22,000
-7,100
| -24% | -$181K |
|
3175
Sabra Healthcare REIT
SBRA
$5.65B
| $567K | ﹤0.01% |
29,963
-8,983
| -23% | -$166K |
|
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.