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 | |
|---|---|---|---|---|---|---|
4401
CALL
State Street Multi-Asset Real Return ETF
RLY
$1.26B
| $169K | ﹤0.01% |
+4,100
| New | +$129K |
|
|
HITI
4402
CALL
High Tide
HITI
$180M
| $169K | ﹤0.01% |
63,800
+48,800
| +325% | +$145K |
|
4403
Agios Pharmaceuticals
AGIO
$2.08B
| $169K | ﹤0.01% |
+6,209
| New | +$218K |
|
4404
CALL
First Busey Corp
BUSE
$2.56B
| $169K | ﹤0.01% |
7,100
+6,500
| +1,083% | +$153K |
|
4405
CALL
Clearwater Paper
CLW
$349M
| $169K | ﹤0.01% |
9,700
+4,700
| +94% | +$86.7K |
|
4406
Unusual Whales Subversive Democratic Trading ETF
NANC
$268M
| $169K | ﹤0.01% |
3,694
+2,933
| +385% | +$133K |
|
4407
PUT
Fulcrum Therapeutics
FULC
$241M
| $169K | ﹤0.01% |
+14,900
| New | +$152K |
|
4408
PUT
HNI Corp
HNI
$3.08B
| $168K | ﹤0.01% |
+4,000
| New | +$169K |
|
4409
Televisa
TV
$1.49B
| $168K | ﹤0.01% |
57,704
+14,475
| +33% | +$39.5K |
|
4410
CALL
AudioEye
AEYE
$71.5M
| $168K | ﹤0.01% |
16,800
+16,600
| +8,300% | +$214K |
|
4411
PUT
Bar Harbor Bankshares
BHB
$665M
| $168K | ﹤0.01% |
5,400
| – | – |
|
4412
PUT
Delcath Systems
DCTH
$400M
| $168K | ﹤0.01% |
16,600
+15,600
| +1,560% | +$155K |
|
4413
ICICI Bank
IBN
$107B
| $168K | ﹤0.01% |
5,625
-318
| -5% | -$9.76K |
|
4414
Atlanta Braves Holdings Series A
BATRA
$3.51B
| $167K | ﹤0.01% |
3,938
+305
| +8% | +$13.1K |
|
|
DENN
4415
PUT
DELISTED
Denny's
DENN
| $167K | ﹤0.01% |
26,900
-19,900
| -43% | -$113K |
|
4416
CALL
Dominari Holdings
DOMH
$50.4M
| $167K | ﹤0.01% |
33,800
-86,600
| -72% | -$442K |
|
|
MBX
4417
CALL
MBX Biosciences
MBX
$3.04B
| $167K | ﹤0.01% |
5,300
-22,100
| -81% | -$536K |
|
4418
Outlook Therapeutics
OTLK
$187M
| $167K | ﹤0.01% |
105,797
+16,556
| +19% | +$26.5K |
|
4419
CALL
Apple Hospitality REIT
APLE
$3.97B
| $167K | ﹤0.01% |
14,100
-6,400
| -31% | -$75.1K |
|
4420
Korea Electric Power
KEP
$14.6B
| $167K | ﹤0.01% |
10,124
-23,622
| -70% | -$374K |
|
|
NA
4421
CALL
Nano Labs
NA
$42.2M
| $167K | ﹤0.01% |
53,000
-21,700
| -29% | -$93.2K |
|
4422
PUT
BBB Foods
TBBB
$4.76B
| $167K | ﹤0.01% |
5,000
+4,800
| +2,400% | +$144K |
|
4423
CALL
Exponent
EXPO
$3.19B
| $167K | ﹤0.01% |
+2,400
| New | +$169K |
|
|
HAPN
4424
PUT
Happen Inc
HAPN
$2.14B
| $167K | ﹤0.01% |
8,800
-5,500
| -38% | -$97.2K |
|
|
ABVX
4425
Abivax
ABVX
$10.4B
| $167K | ﹤0.01% |
+1,235
| New | +$135K |
|
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.