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 | |
|---|---|---|---|---|---|---|
6901
Wipro
WIT
$19.3B
| $11.5K | ﹤0.01% |
4,052
-477
| -11% | -$1.3K |
|
|
BSOL
6902
PUT
Bitwise Solana Staking ETF
BSOL
$553M
| $11.5K | ﹤0.01% |
+700
| New | +$13K |
|
6903
Lakeland Industries
LAKE
$109M
| $11.5K | ﹤0.01% |
1,296
-3,354
| -72% | -$47.1K |
|
6904
IZEA Worldwide
IZEA
$59.2M
| $11.4K | ﹤0.01% |
2,611
-1,501
| -37% | -$7.3K |
|
|
CTEV
6905
Claritev Corp
CTEV
$402M
| $11.4K | ﹤0.01% |
267
+60
| +29% | +$3.05K |
|
|
CORD
6906
T-REX 2X Inverse CRWV Daily Target ETF
CORD
$9.85M
| $11.4K | ﹤0.01% |
+286
| New | +$9.73K |
|
6907
AZZ Inc
AZZ
$4.36B
| $11.4K | ﹤0.01% |
+106
| New | +$11K |
|
|
ARCX
6908
Tradr 2X Long ACHR Daily ETF
ARCX
$6.7M
| $11.4K | ﹤0.01% |
+317
| New | +$20.6K |
|
6909
PUT
American Public Education
APEI
$910M
| $11.3K | ﹤0.01% |
300
-1,100
| -79% | -$39.4K |
|
|
KEUA
6910
DELISTED
KraneShares European Carbon Allowance Strategy ETF
KEUA
| $11.3K | ﹤0.01% |
402
+393
| +4,367% | +$10.7K |
|
|
TRUE
6911
DELISTED
TrueCar
TRUE
| $11.3K | ﹤0.01% |
+5,008
| New | +$10.7K |
|
6912
PUT
Community Trust Bancorp
CTBI
$1.42B
| $11.3K | ﹤0.01% |
200
| – | – |
|
|
PSTL
6913
PUT
Postal Realty Trust
PSTL
$694M
| $11.3K | ﹤0.01% |
700
-100
| -13% | -$1.54K |
|
6914
CALL
C4 Therapeutics
CCCC
$405M
| $11.3K | ﹤0.01% |
5,900
-23,600
| -80% | -$55.9K |
|
6915
Pyxis Oncology
PYXS
$182M
| $11.3K | ﹤0.01% |
9,790
+2,357
| +32% | +$8.31K |
|
|
PNNT
6916
Pennant Park Investment Corp
PNNT
$217M
| $11.1K | ﹤0.01% |
1,870
+1,370
| +274% | +$8.56K |
|
6917
CALL
Elicio Therapeutics
ELTX
$76.4M
| $11.1K | ﹤0.01% |
1,400
+300
| +27% | +$2.72K |
|
|
UDMY
6918
CALL
DELISTED
Udemy
UDMY
| $11.1K | ﹤0.01% |
1,900
-31,400
| -94% | -$183K |
|
6919
Wheels Up
UP
$217M
| $11.1K | ﹤0.01% |
847
-6,777
| -89% | -$154K |
|
6920
Kite Realty
KRG
$5.88B
| $11.1K | ﹤0.01% |
+463
| New | +$10.5K |
|
|
GGRP
6921
Glimpse Group
GGRP
$18.6M
| $11.1K | ﹤0.01% |
11,957
+2,920
| +32% | +$3.71K |
|
|
IRD
6922
CALL
Opus Genetics
IRD
$317M
| $11.1K | ﹤0.01% |
+5,500
| New | +$11.2K |
|
|
OMDA
6923
PUT
Omada Health Inc
OMDA
$1.17B
| $11K | ﹤0.01% |
+700
| New | +$14.2K |
|
|
SEVN
6924
Seven Hills Realty Trust
SEVN
$171M
| $11K | ﹤0.01% |
1,241
+354
| +40% | +$3.32K |
|
6925
PUT
OptimizeRx
OPRX
$118M
| $11K | ﹤0.01% |
900
-4,300
| -83% | -$70.3K |
|
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.