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 | |
|---|---|---|---|---|---|---|
|
EWCZ
8176
DELISTED
European Wax Center
EWCZ
| $446 | ﹤0.01% |
124
-8,563
| -99% | -$32K |
|
8177
Broadwind
BWEN
$112M
| $444 | ﹤0.01% |
157
-2,223
| -93% | -$5.83K |
|
|
SKYA
8178
SkyAI Inc
SKYA
$55.9M
| $442 | ﹤0.01% |
+218
| New | +$841 |
|
|
TOUR
8179
CALL
Tuniu
TOUR
$55M
| $434 | ﹤0.01% |
+70
| New | +$551 |
|
|
AMDD
8180
Direxion Daily AMD Bear 1X ETF
AMDD
$20.7M
| $432 | ﹤0.01% |
+5
| New | +$473 |
|
|
SEV
8181
CALL
Aptera Motors
SEV
$66.8M
| $429 | ﹤0.01% |
+100
| New | +$626 |
|
|
SEV
8182
PUT
Aptera Motors
SEV
$66.8M
| $429 | ﹤0.01% |
+100
| New | +$626 |
|
8183
ABVC BioPharma
ABVC
$26.5M
| $417 | ﹤0.01% |
196
-912
| -82% | -$2.44K |
|
8184
CALL
Duluth Holdings
DLTH
$162M
| $416 | ﹤0.01% |
200
-2,500
| -93% | -$7.4K |
|
|
SMU
8185
Tradr 2X Long SMR Daily ETF
SMU
$49.7M
| $413 | ﹤0.01% |
+13
| New | +$2.46K |
|
8186
PUT
Visteon
VC
$2.82B
| $409 | ﹤0.01% |
100
-2,600
| -96% | -$275K |
|
|
TEF
8187
PUT
DELISTED
Telefonica
TEF
| $405 | ﹤0.01% |
100
-3,500
| -97% | -$15.8K |
|
|
YSG
8188
PUT
Yatsen Holding
YSG
$318M
| $389 | ﹤0.01% |
100
-1,300
| -93% | -$8.26K |
|
|
ETQ
8189
DELISTED
T-Rex 2X Inverse Ether Daily Target ETF
ETQ
| $388 | ﹤0.01% |
+9
| New | +$363 |
|
8190
CALL
Identive
INVE
$65.1M
| $384 | ﹤0.01% |
+100
| New | +$361 |
|
|
8191
PUT
Identive
INVE
$65.1M
| $384 | ﹤0.01% |
100
-400
| -80% | -$1.44K |
|
|
STKL
8192
PUT
DELISTED
SunOpta
STKL
| $380 | ﹤0.01% |
+100
| New | +$454 |
|
8193
CALL
Alpha Teknova
TKNO
$260M
| $380 | ﹤0.01% |
+100
| New | +$487 |
|
8194
CALL
Playboy Inc
PLBY
$143M
| $376 | ﹤0.01% |
200
-11,100
| -98% | -$18.1K |
|
8195
PUT
VTEX
VTEX
$718M
| $376 | ﹤0.01% |
100
-500
| -83% | -$2.05K |
|
8196
PUT
Gerdau
GGB
$9.48B
| $369 | ﹤0.01% |
100
-2,000
| -95% | -$6.99K |
|
8197
Goosehead Insurance
GSHD
$1.47B
| $368 | ﹤0.01% |
5
-953
| -99% | -$67.9K |
|
8198
CALL
Shattuck Labs
STTK
$672M
| $365 | ﹤0.01% |
100
-21,500
| -100% | -$51.3K |
|
8199
PUT
Talkspace
TALK
$874M
| $363 | ﹤0.01% |
+100
| New | +$317 |
|
8200
PUT
BARK
BARK
$76.4M
| $361 | ﹤0.01% |
30
-85
| -74% | -$1.26K |
|
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.