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 | |
|---|---|---|---|---|---|---|
5126
PUT
Brookfield Renewable
BEPC
$6.08B
| $88.2K | ﹤0.01% |
2,300
-1,700
| -43% | -$68.4K |
|
5127
CALL
Sturm, Ruger & Co
RGR
$594M
| $88.2K | ﹤0.01% |
2,700
-25,400
| -90% | -$941K |
|
5128
CALL
The Bancorp
TBBK
$2.79B
| $87.8K | ﹤0.01% |
1,300
-600
| -32% | -$41.4K |
|
5129
CALL
Pediatrix Medical
MD
$2.18B
| $87.7K | ﹤0.01% |
4,100
-300
| -7% | -$6.15K |
|
5130
PIMCO 15+ Year US TIPS Index Exchange-Traded Fund
LTPZ
$690M
| $87.5K | ﹤0.01% |
+1,690
| New | +$89.8K |
|
5131
CALL
Crexendo
CXDO
$223M
| $87.3K | ﹤0.01% |
13,500
-11,700
| -46% | -$76.6K |
|
|
DHC
5132
PUT
Diversified Healthcare Trust
DHC
$2.15B
| $87.3K | ﹤0.01% |
18,000
+400
| +2% | +$1.81K |
|
5133
PUT
Procore
PCOR
$8.26B
| $87.3K | ﹤0.01% |
1,200
| – | – |
|
|
SLI
5134
PUT
Standard Lithium
SLI
$502M
| $87.2K | ﹤0.01% |
19,500
+1,200
| +7% | +$5.08K |
|
5135
Gulfport Energy Corp
GPOR
$2.9B
| $87.1K | ﹤0.01% |
+419
| New | +$83.5K |
|
5136
CALL
Coherus Oncology
CHRS
$217M
| $87K | ﹤0.01% |
61,300
-1,400
| -2% | -$2.04K |
|
5137
CALL
Impinj
PI
$4.62B
| $87K | ﹤0.01% |
500
-5,000
| -91% | -$891K |
|
|
ELME
5138
CALL
Elme Communities
ELME
$143M
| $87K | ﹤0.01% |
+5,000
| New | +$84.8K |
|
5139
Personalis
PSNL
$1.35B
| $86.9K | ﹤0.01% |
10,923
+4,847
| +80% | +$42.4K |
|
5140
CALL
One Stop Systems
OSS
$303M
| $86.9K | ﹤0.01% |
12,100
-6,000
| -33% | -$35.5K |
|
|
NAKA
5141
Nakamoto Inc
NAKA
$82.7M
| $86.9K | ﹤0.01% |
6,185
-3,876
| -39% | -$101K |
|
5142
GraniteShares ETF Trust GraniteShares 2x Long BABA Daily ETF
BABX
$110M
| $86.7K | ﹤0.01% |
+2,407
| New | +$110K |
|
5143
PUT
Manhattan Associates
MANH
$11.2B
| $86.7K | ﹤0.01% |
+500
| New | +$91.4K |
|
|
LGO
5144
CALL
Largo
LGO
$59.8M
| $86.5K | ﹤0.01% |
92,300
+71,700
| +348% | +$85.1K |
|
5145
PUT
Phreesia
PHR
$663M
| $86.3K | ﹤0.01% |
5,100
-13,400
| -72% | -$276K |
|
5146
Achieve Life Sciences
ACHV
$659M
| $86.2K | ﹤0.01% |
+17,338
| New | +$75.6K |
|
|
PKST
5147
PUT
DELISTED
Peakstone Realty Trust
PKST
| $86.1K | ﹤0.01% |
6,000
+5,600
| +1,400% | +$77.2K |
|
|
TRTX
5148
CALL
TPG RE Finance Trust
TRTX
$612M
| $86.1K | ﹤0.01% |
10,000
+5,200
| +108% | +$46.1K |
|
|
PDM
5149
CALL
Piedmont Realty Trust
PDM
$1.21B
| $85.9K | ﹤0.01% |
10,300
-7,400
| -42% | -$61.8K |
|
5150
Goldman Sachs ETF Trust Goldman Sachs S&P 500 Premium Income ETF
GPIX
$4.9B
| $85.9K | ﹤0.01% |
1,626
+72
| +5% | +$3.77K |
|
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.