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 | |
|---|---|---|---|---|---|---|
6426
CALL
Encompass Health
EHC
$11B
| $21.2K | ﹤0.01% |
200
-200
| -50% | -$23.2K |
|
6427
CALL
Atlantic Union Bankshares
AUB
$6.02B
| $21.2K | ﹤0.01% |
600
| – | – |
|
6428
AvePoint
AVPT
$2.76B
| $21.2K | ﹤0.01% |
+1,524
| New | +$21.1K |
|
|
BLFY
6429
CALL
DELISTED
Blue Foundry Bancorp
BLFY
| $21.1K | ﹤0.01% |
+1,700
| New | +$17K |
|
6430
TaskUs
TASK
$556M
| $21.1K | ﹤0.01% |
1,792
-4,497
| -72% | -$57.5K |
|
6431
UFP Technologies
UFPT
$1.97B
| $21.1K | ﹤0.01% |
95
-64
| -40% | -$13.7K |
|
6432
Themes Generative Artificial Intelligence ETF
WISE
$27.1M
| $21.1K | ﹤0.01% |
+541
| New | +$23.2K |
|
6433
CALL
Upbound Group
UPBD
$1.13B
| $21.1K | ﹤0.01% |
1,200
-5,200
| -81% | -$101K |
|
|
MNRS
6434
CALL
Grayscale Bitcoin Miners ETF
MNRS
$12.1M
| $21K | ﹤0.01% |
700
+500
| +250% | +$20.1K |
|
6435
CALL
Virtus Newfleet Short Duration High Yield Bond ETF
VSHY
$31M
| $21K | ﹤0.01% |
+500
| New | +$11K |
|
6436
CALL
Mission Produce
AVO
$1.11B
| $20.9K | ﹤0.01% |
1,800
-1,800
| -50% | -$21.6K |
|
6437
PUT
Rackspace Technology
RXT
$1.05B
| $20.9K | ﹤0.01% |
21,500
+12,900
| +150% | +$16.2K |
|
|
API
6438
Agora
API
$338M
| $20.9K | ﹤0.01% |
+5,125
| New | +$18.8K |
|
6439
CALL
Arcturus Therapeutics
ARCT
$164M
| $20.8K | ﹤0.01% |
3,400
-42,900
| -93% | -$463K |
|
6440
Home BancShares
HOMB
$6.23B
| $20.8K | ﹤0.01% |
750
-1,953
| -72% | -$54.2K |
|
6441
PUT
Sasol
SSL
$7.5B
| $20.8K | ﹤0.01% |
3,200
+2,800
| +700% | +$17.7K |
|
6442
PUT
Hyster-Yale Materials Handling
HY
$599M
| $20.8K | ﹤0.01% |
+700
| New | +$23.1K |
|
|
CUK
6443
DELISTED
Carnival PLC
CUK
| $20.7K | ﹤0.01% |
+683
| New | +$17.6K |
|
6444
CALL
TherapeuticsMD
TXMD
$23.5M
| $20.7K | ﹤0.01% |
+12,700
| New | +$18.4K |
|
6445
CALL
Cineverse
CNVS
$56.2M
| $20.7K | ﹤0.01% |
9,800
+8,400
| +600% | +$22.8K |
|
6446
PUT
AutoNation
AN
$7.11B
| $20.6K | ﹤0.01% |
100
-5,300
| -98% | -$1.1M |
|
6447
CALL
Zevia
ZVIA
$122M
| $20.6K | ﹤0.01% |
8,900
+1,500
| +20% | +$3.73K |
|
6448
CALL
PROG Holdings
PRG
$1.75B
| $20.6K | ﹤0.01% |
700
-1,500
| -68% | -$44.7K |
|
6449
CALL
Worthington Enterprises
WOR
$2.75B
| $20.6K | ﹤0.01% |
400
-9,100
| -96% | -$502K |
|
6450
ProShares UltraShort Euro
EUO
$34.7M
| $20.6K | ﹤0.01% |
+727
| New | +$20.9K |
|
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.