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 | |
|---|---|---|---|---|---|---|
1851
Millicom
TIGO
$15.8B
| $2.33M | ﹤0.01% |
42,040
-9,313
| -18% | -$469K |
|
1852
CALL
Celanese
CE
$5.09B
| $2.33M | ﹤0.01% |
55,100
-21,800
| -28% | -$889K |
|
1853
Equinox Gold
EQX
$7.32B
| $2.33M | ﹤0.01% |
+165,811
| New | +$2.09M |
|
|
QLTB
1854
CALL
DELISTED
ISHARES BAA BA RATED CORP BOND FUND
QLTB
| $2.33M | ﹤0.01% |
11,500
-12,100
| -51% | -$2.45M |
|
|
VZLA
1855
PUT
Vizsla Silver
VZLA
$1.16B
| $2.32M | ﹤0.01% |
424,700
+424,400
| +141,467% | +$1.99M |
|
1856
Comstock Resources
CRK
$3.97B
| $2.32M | ﹤0.01% |
100,159
+21,753
| +28% | +$479K |
|
1857
PUT
Doximity
DOCS
$3.67B
| $2.32M | ﹤0.01% |
52,400
-3,900
| -7% | -$219K |
|
|
PPL
1858
PUT
PPL Corp
PPL
$27.3B
| $2.32M | ﹤0.01% |
66,200
+9,600
| +17% | +$346K |
|
1859
General Mills
GIS
$19.2B
| $2.32M | ﹤0.01% |
49,795
-34,862
| -41% | -$1.66M |
|
1860
Direxion Daily FTSE China Bear 3X ETF
YANG
$86.8M
| $2.32M | ﹤0.01% |
92,092
+52,022
| +130% | +$1.22M |
|
1861
SiriusXM
SIRI
$10B
| $2.31M | ﹤0.01% |
115,727
+89,357
| +339% | +$1.92M |
|
1862
CALL
FIVE9
FIVN
$1.77B
| $2.31M | ﹤0.01% |
115,200
-97,300
| -46% | -$2.07M |
|
|
PPLC
1863
PUT
DELISTED
PortfolioPlus S&P 500 ETF
PPLC
| $2.31M | ﹤0.01% |
48,600
+5,300
| +12% | +$251K |
|
1864
CALL
Onto Innovation
ONTO
$13.6B
| $2.3M | ﹤0.01% |
14,600
-10,500
| -42% | -$1.49M |
|
1865
PUT
Novavax
NVAX
$1.23B
| $2.3M | ﹤0.01% |
342,200
-170,100
| -33% | -$1.28M |
|
1866
CALL
Neogen
NEOG
$2.05B
| $2.3M | ﹤0.01% |
328,400
+304,500
| +1,274% | +$1.92M |
|
1867
CALL
Patterson-UTI
PTEN
$3.87B
| $2.29M | ﹤0.01% |
375,300
+207,500
| +124% | +$1.24M |
|
1868
PUT
Vipshop
VIPS
$6.84B
| $2.29M | ﹤0.01% |
129,600
-136,300
| -51% | -$2.62M |
|
1869
CALL
Ramaco Resources Class A
METC
$676M
| $2.29M | ﹤0.01% |
127,300
+91,200
| +253% | +$2.4M |
|
1870
CALL
Vanguard ESG US Corporate Bond ETF
VCEB
$1.18B
| $2.29M | ﹤0.01% |
21,400
+12,800
| +149% | +$820K |
|
1871
PUT
CoreCivic
CXW
$3.1B
| $2.29M | ﹤0.01% |
119,700
-101,100
| -46% | -$1.85M |
|
|
EXAS
1872
DELISTED
Exact Sciences
EXAS
| $2.29M | ﹤0.01% |
+22,521
| New | +$1.81M |
|
|
EXAS
1873
PUT
DELISTED
Exact Sciences
EXAS
| $2.29M | ﹤0.01% |
22,500
-42,000
| -65% | -$3.37M |
|
1874
PUT
Navitas Semiconductor
NVTS
$2.66B
| $2.28M | ﹤0.01% |
319,700
+27,200
| +9% | +$262K |
|
1875
CleanSpark
CLSK
$3.73B
| $2.28M | ﹤0.01% |
225,526
-25,706
| -10% | -$385K |
|
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.