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 | |
|---|---|---|---|---|---|---|
3576
CALL
Lightbridge
LTBR
$259M
| $382K | ﹤0.01% |
30,200
-109,300
| -78% | -$2.1M |
|
3577
CALL
Nuvectis Pharma
NVCT
$625M
| $381K | ﹤0.01% |
50,500
-4,500
| -8% | -$29.3K |
|
3578
Upwork
UPWK
$1.21B
| $380K | ﹤0.01% |
19,197
-41,005
| -68% | -$752K |
|
3579
British American Tobacco
BTI
$134B
| $380K | ﹤0.01% |
+6,717
| New | +$366K |
|
3580
PUT
PTC Therapeutics
PTCT
$6.25B
| $380K | ﹤0.01% |
5,000
+1,300
| +35% | +$94.5K |
|
3581
Revolve Group
RVLV
$1.92B
| $379K | ﹤0.01% |
12,568
-1,341
| -10% | -$32.4K |
|
3582
PUT
Americold
COLD
$4.17B
| $379K | ﹤0.01% |
29,500
-12,800
| -30% | -$157K |
|
3583
CALL
Imperial Petroleum
IMPP
$212M
| $379K | ﹤0.01% |
104,700
+91,100
| +670% | +$448K |
|
3584
PUT
OneMain Financial
OMF
$7.19B
| $378K | ﹤0.01% |
5,600
-61,100
| -92% | -$3.72M |
|
|
MSTX
3585
Defiance Daily Target 2x Long MSTR ETF
MSTX
$158M
| $378K | ﹤0.01% |
+9,820
| New | +$1.07M |
|
|
LNW
3586
DELISTED
Light & Wonder
LNW
| $378K | ﹤0.01% |
+3,666
| New | +$288K |
|
3587
PUT
Qfin Holdings
QFIN
$1.66B
| $378K | ﹤0.01% |
19,600
+5,800
| +42% | +$130K |
|
3588
CALL
DoubleVerify
DV
$1.73B
| $378K | ﹤0.01% |
33,000
-50,200
| -60% | -$554K |
|
3589
PUT
UFP Technologies
UFPT
$2B
| $377K | ﹤0.01% |
1,700
+100
| +6% | +$21.4K |
|
3590
iShares JPMorgan USD Emerging Markets Bond ETF
EMB
$15B
| $377K | ﹤0.01% |
3,919
+3,557
| +983% | +$342K |
|
3591
PUT
Freedom Holding
FRHC
$9.84B
| $377K | ﹤0.01% |
3,100
-4,000
| -56% | -$580K |
|
3592
CALL
LiveWire
LVWR
$399M
| $377K | ﹤0.01% |
85,200
+9,900
| +13% | +$47.6K |
|
3593
PUT
Helen of Troy
HELE
$672M
| $376K | ﹤0.01% |
17,700
+7,500
| +74% | +$153K |
|
3594
CALL
Lattice Semiconductor
LSCC
$16.4B
| $375K | ﹤0.01% |
5,100
-25,800
| -83% | -$1.84M |
|
3595
CALL
Apogee Enterprises
APOG
$873M
| $375K | ﹤0.01% |
10,300
+8,900
| +636% | +$336K |
|
3596
CALL
Pentair
PNR
$10.8B
| $375K | ﹤0.01% |
3,600
+200
| +6% | +$21.4K |
|
3597
CALL
Microbot Medical
MBOT
$113M
| $374K | ﹤0.01% |
187,100
-196,900
| -51% | -$466K |
|
3598
Public Storage
PSA
$61.7B
| $374K | ﹤0.01% |
+1,442
| New | +$403K |
|
3599
Cemex
CX
$17.3B
| $373K | ﹤0.01% |
32,478
+13,899
| +75% | +$144K |
|
3600
PUT
Power Integrations
POWI
$3.3B
| $373K | ﹤0.01% |
10,500
+10,000
| +2,000% | +$379K |
|
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.