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 | |
|---|---|---|---|---|---|---|
5101
PUT
Precigen
PGEN
$2.24B
| $89.9K | ﹤0.01% |
21,500
-59,700
| -74% | -$231K |
|
|
TOPW
5102
Roundhill Top WeeklyPay ETF
TOPW
$144M
| $89.8K | ﹤0.01% |
2,146
+467
| +28% | +$22.9K |
|
5103
PUT
Veralto
VLTO
$23B
| $89.8K | ﹤0.01% |
900
+800
| +800% | +$80.9K |
|
5104
Regenxbio
RGNX
$620M
| $89.8K | ﹤0.01% |
6,234
-6,143
| -50% | -$76.6K |
|
|
BMNU
5105
T-REX 2X Long BMNR Daily Target ETF
BMNU
$233M
| $89.7K | ﹤0.01% |
1,878
+1,675
| +825% | +$256K |
|
5106
CALL
Laser Photonics
LASE
$49.2M
| $89.7K | ﹤0.01% |
36,300
-64,700
| -64% | -$217K |
|
|
NTSK
5107
PUT
Netskope Inc
NTSK
$5.09B
| $89.5K | ﹤0.01% |
5,100
+3,400
| +200% | +$70.9K |
|
5108
ProQR Therapeutics
PRQR
$243M
| $89.4K | ﹤0.01% |
+44,269
| New | +$103K |
|
|
NFLW
5109
Roundhill NFLX WeeklyPay ETF
NFLW
$6.67M
| $89.3K | ﹤0.01% |
+3,260
| New | +$112K |
|
5110
Rentokil
RTO
$11.8B
| $89.2K | ﹤0.01% |
+3,027
| New | +$84.1K |
|
5111
CALL
Roper Technologies
ROP
$38.8B
| $89K | ﹤0.01% |
200
-4,100
| -95% | -$1.9M |
|
5112
MYR Group
MYRG
$5.19B
| $88.9K | ﹤0.01% |
407
+107
| +36% | +$23.3K |
|
5113
PUT
Hubbell
HUBB
$25B
| $88.8K | ﹤0.01% |
200
+100
| +100% | +$43.8K |
|
5114
PUT
Credit Acceptance
CACC
$5.95B
| $88.7K | ﹤0.01% |
200
-1,000
| -83% | -$464K |
|
5115
Meritage Homes
MTH
$4.58B
| $88.6K | ﹤0.01% |
1,346
-10,629
| -89% | -$736K |
|
5116
Quantum-Si Incorporated
QSI
$155M
| $88.6K | ﹤0.01% |
80,507
-73,576
| -48% | -$120K |
|
5117
Amplify Blockchain Technology ETF
BLOK
$1.08B
| $88.5K | ﹤0.01% |
1,556
-1,461
| -48% | -$94.3K |
|
5118
PUT
loanDepot
LDI
$532M
| $88.4K | ﹤0.01% |
42,700
-92,800
| -68% | -$258K |
|
5119
CALL
Axcelis
ACLS
$4.01B
| $88.4K | ﹤0.01% |
1,100
-3,300
| -75% | -$276K |
|
5120
CALL
Kyverna Therapeutics
KYTX
$444M
| $88.4K | ﹤0.01% |
9,400
-16,200
| -63% | -$120K |
|
5121
CALL
Navigator Holdings
NVGS
$1.38B
| $88.3K | ﹤0.01% |
5,100
+1,800
| +55% | +$30.1K |
|
5122
PUT
GoPro
GPRO
$130M
| $88.3K | ﹤0.01% |
62,600
-23,000
| -27% | -$41.7K |
|
|
NSLR
5123
Neostellar Capital Corp
NSLR
$269M
| $88.2K | ﹤0.01% |
+9,347
| New | +$88K |
|
5124
CALL
Consolidated Water Co
CWCO
$467M
| $88.2K | ﹤0.01% |
2,500
-100
| -4% | -$3.49K |
|
5125
PUT
Ingredion
INGR
$6.27B
| $88.2K | ﹤0.01% |
800
-3,200
| -80% | -$361K |
|
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.