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 | |
|---|---|---|---|---|---|---|
7151
CALL
Getty Images
GETY
$159M
| $7.77K | ﹤0.01% |
5,800
-308,300
| -98% | -$531K |
|
7152
WEX
WEX
$6.42B
| $7.75K | ﹤0.01% |
52
-40
| -43% | -$6.03K |
|
7153
PUT
Westrock Coffee
WEST
$798M
| $7.73K | ﹤0.01% |
1,900
+1,400
| +280% | +$6.13K |
|
7154
Metropolitan Bank Holding Corp
MCB
$1.15B
| $7.71K | ﹤0.01% |
101
+3
| +3% | +$222 |
|
7155
PUT
Progyny
PGNY
$2.46B
| $7.7K | ﹤0.01% |
300
-5,500
| -95% | -$126K |
|
|
VIVO
7156
PUT
VivoPower PLC
VIVO
$97.4M
| $7.7K | ﹤0.01% |
3,400
-2,600
| -43% | -$8.93K |
|
7157
Tuttle Capital Daily 2X Inverse Regional Banks ETF
SKRE
$5.07M
| $7.68K | ﹤0.01% |
+843
| New | +$8.44K |
|
7158
Equitable Holdings
EQH
$13.2B
| $7.67K | ﹤0.01% |
+161
| New | +$7.63K |
|
|
7159
CALL
Metropolitan Bank Holding Corp
MCB
$1.15B
| $7.64K | ﹤0.01% |
+100
| New | +$7.41K |
|
7160
CALL
Kartoon Studios
TOON
$34M
| $7.63K | ﹤0.01% |
+10,600
| New | +$7.82K |
|
7161
CALL
SelectQuote
SLQT
$122M
| $7.61K | ﹤0.01% |
5,400
+1,800
| +50% | +$3.01K |
|
7162
iShares Mortgage Real Estate ETF
REM
$549M
| $7.61K | ﹤0.01% |
343
-4,114
| -92% | -$91.5K |
|
|
SLI
7163
Standard Lithium
SLI
$475M
| $7.6K | ﹤0.01% |
1,700
-181,968
| -99% | -$771K |
|
|
UCTT
7164
PUT
Ultra Clean Holdings
UCTT
$3.12B
| $7.6K | ﹤0.01% |
300
-400
| -57% | -$10.6K |
|
7165
Atomera
ATOM
$173M
| $7.57K | ﹤0.01% |
3,426
-34,286
| -91% | -$104K |
|
7166
Arq
ARQ
$83.3M
| $7.56K | ﹤0.01% |
+2,311
| New | +$11.3K |
|
7167
CALL
Origin Bancorp
OBK
$1.7B
| $7.52K | ﹤0.01% |
+200
| New | +$7.17K |
|
7168
PUT
Cognyte Software
CGNT
$655M
| $7.52K | ﹤0.01% |
800
-400
| -33% | -$3.46K |
|
7169
PUT
nLIGHT
LASR
$3.33B
| $7.5K | ﹤0.01% |
200
-100
| -33% | -$3.34K |
|
7170
PUT
Element Solutions
ESI
$8.48B
| $7.5K | ﹤0.01% |
300
-11,800
| -98% | -$306K |
|
7171
PUT
Dole
DOLE
$1.38B
| $7.5K | ﹤0.01% |
500
-24,600
| -98% | -$343K |
|
7172
CALL
Anixa Biosciences
ANIX
$118M
| $7.49K | ﹤0.01% |
2,400
+500
| +26% | +$2.05K |
|
7173
CALL
Mayville Engineering Co
MEC
$648M
| $7.49K | ﹤0.01% |
+400
| New | +$6.52K |
|
7174
PUT
Myers Industries
MYE
$1.24B
| $7.49K | ﹤0.01% |
400
| – | – |
|
7175
SPS Commerce
SPSC
$2.55B
| $7.49K | ﹤0.01% |
84
+73
| +664% | +$6.77K |
|
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.