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 | |
|---|---|---|---|---|---|---|
3101
Henry Schein
HSIC
$9.64B
| $611K | ﹤0.01% |
+8,085
| New | +$569K |
|
3102
CALL
Nu Skin
NUS
$250M
| $611K | ﹤0.01% |
63,500
+51,500
| +429% | +$533K |
|
3103
CALL
OppFi
OPFI
$804M
| $611K | ﹤0.01% |
58,400
-118,800
| -67% | -$1.2M |
|
3104
Wolfspeed
WOLF
$1.24B
| $610K | ﹤0.01% |
35,054
+34,986
| +51,450% | +$803K |
|
3105
PUT
AMC Entertainment Holdings
AMC
$2.24B
| $610K | ﹤0.01% |
391,100
-652,800
| -63% | -$1.56M |
|
3106
CALL
Perdoceo Education
PRDO
$1.99B
| $610K | ﹤0.01% |
+20,800
| New | +$657K |
|
3107
State Street SPDR S&P MIDCAP 400 ETF Trust
MDY
$26.9B
| $610K | ﹤0.01% |
1,011
-3,792
| -79% | -$2.27M |
|
3108
PUT
RXO
RXO
$3.98B
| $609K | ﹤0.01% |
48,200
-58,800
| -55% | -$867K |
|
3109
PUT
Waters Corp
WAT
$36.4B
| $608K | ﹤0.01% |
1,600
-400
| -20% | -$147K |
|
3110
CALL
Invesco CurrencyShares Euro Currency Trust
FXE
$341M
| $607K | ﹤0.01% |
5,600
+2,100
| +60% | +$226K |
|
3111
State Street SPDR Portfolio Long Term Treasury ETF
SPTL
$10.6B
| $607K | ﹤0.01% |
22,936
-10,417
| -31% | -$281K |
|
|
CBL
3112
CBL Properties
CBL
$1.81B
| $607K | ﹤0.01% |
+16,405
| New | +$535K |
|
3113
CALL
Lightpath Technologies
LPTH
$686M
| $605K | ﹤0.01% |
56,000
+27,000
| +93% | +$219K |
|
3114
Tiptree Inc
TIPT
$678M
| $604K | ﹤0.01% |
33,069
+14,437
| +77% | +$263K |
|
3115
Constellation Brands
STZ
$22.2B
| $604K | ﹤0.01% |
4,376
-19,825
| -82% | -$2.72M |
|
|
CGAU
3116
CALL
Centerra Gold
CGAU
$3.27B
| $604K | ﹤0.01% |
42,000
+29,900
| +247% | +$374K |
|
|
AMTM
3117
PUT
Amentum Holdings
AMTM
$5.59B
| $603K | ﹤0.01% |
20,800
-2,500
| -11% | -$63.9K |
|
3118
CALL
Sana Biotechnology
SANA
$913M
| $603K | ﹤0.01% |
148,200
+119,300
| +413% | +$534K |
|
3119
Hallador Energy
HNRG
$717M
| $602K | ﹤0.01% |
31,631
-5,760
| -15% | -$117K |
|
3120
Leggett & Platt
LEG
$1.5B
| $601K | ﹤0.01% |
54,605
+51,125
| +1,469% | +$503K |
|
3121
PUT
NewAmsterdam Pharma
NAMS
$3.53B
| $600K | ﹤0.01% |
17,100
+2,300
| +16% | +$83.7K |
|
|
SVM
3122
PUT
Silvercorp Metals
SVM
$2.16B
| $600K | ﹤0.01% |
71,900
-5,300
| -7% | -$38.5K |
|
3123
PUT
Bit Digital
BTBT
$477M
| $599K | ﹤0.01% |
316,900
-168,000
| -35% | -$486K |
|
3124
CALL
Lloyds Banking Group
LYG
$89B
| $599K | ﹤0.01% |
113,000
+15,200
| +16% | +$73.6K |
|
|
SVM
3125
Silvercorp Metals
SVM
$2.16B
| $599K | ﹤0.01% |
71,788
-1,927
| -3% | -$14K |
|
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.