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 | |
|---|---|---|---|---|---|---|
3926
CALL
Hagerty
HGTY
$1.22B
| $269K | ﹤0.01% |
20,000
-1,900
| -9% | -$23.7K |
|
3927
PUT
Zevra Therapeutics
ZVRA
$568M
| $269K | ﹤0.01% |
30,000
+8,100
| +37% | +$76.6K |
|
3928
CALL
Inhibrx
INBX
$1.16B
| $269K | ﹤0.01% |
3,400
+3,300
| +3,300% | +$225K |
|
|
3929
PUT
Inhibrx
INBX
$1.16B
| $269K | ﹤0.01% |
3,400
+3,200
| +1,600% | +$218K |
|
|
FOLD
3930
DELISTED
Amicus Therapeutics
FOLD
| $269K | ﹤0.01% |
+18,857
| New | +$185K |
|
3931
Garrett Motion
GTX
$5.41B
| $268K | ﹤0.01% |
15,403
+7,633
| +98% | +$122K |
|
3932
Philips
PHG
$25.3B
| $268K | ﹤0.01% |
10,271
-30,817
| -75% | -$822K |
|
|
BTCI
3933
NEOS Bitcoin High Income ETF
BTCI
$1.09B
| $268K | ﹤0.01% |
6,091
-3,548
| -37% | -$183K |
|
3934
PUT
PVH
PVH
$3.98B
| $268K | ﹤0.01% |
4,000
-13,100
| -77% | -$1.02M |
|
|
STEX
3935
Streamex Corp
STEX
$69M
| $268K | ﹤0.01% |
88,463
+56,027
| +173% | +$251K |
|
3936
PUT
Atlanta Braves Holdings Series B
BATRK
$3.26B
| $268K | ﹤0.01% |
6,300
-27,400
| -81% | -$1.08M |
|
3937
PUT
Kemper
KMPR
$1.8B
| $268K | ﹤0.01% |
+6,600
| New | +$283K |
|
3938
Ashland
ASH
$3.33B
| $267K | ﹤0.01% |
4,543
-2,962
| -39% | -$157K |
|
|
TMQ
3939
PUT
Trilogy Metals
TMQ
$498M
| $266K | ﹤0.01% |
61,800
+61,200
| +10,200% | +$288K |
|
3940
PUT
Westlake Corp
WLK
$9.21B
| $266K | ﹤0.01% |
3,600
+2,100
| +140% | +$149K |
|
3941
CALL
Pinnacle West Capital
PNW
$12.5B
| $266K | ﹤0.01% |
3,000
-8,600
| -74% | -$770K |
|
|
JOYY
3942
PUT
JOYY Inc
JOYY
$3.72B
| $266K | ﹤0.01% |
4,100
-24,100
| -85% | -$1.47M |
|
3943
TMC The Metals Company
TMC
$1.48B
| $265K | ﹤0.01% |
42,890
-405,726
| -90% | -$2.85M |
|
3944
Sterling Infrastructure
STRL
$15.4B
| $265K | ﹤0.01% |
864
-804
| -48% | -$277K |
|
|
CYBR
3945
DELISTED
CyberArk
CYBR
| $265K | ﹤0.01% |
+593
| New | +$285K |
|
3946
CALL
BlackSky Technology
BKSY
$854M
| $264K | ﹤0.01% |
14,100
-50,000
| -78% | -$1.02M |
|
3947
CALL
Offerpad Solutions
OPAD
$18.4M
| $264K | ﹤0.01% |
21,840
+2,970
| +16% | +$65.7K |
|
|
SAIL
3948
SailPoint Inc
SAIL
$9.04B
| $264K | ﹤0.01% |
+13,059
| New | +$272K |
|
3949
CVR Energy
CVI
$3.49B
| $264K | ﹤0.01% |
10,374
-5,936
| -36% | -$202K |
|
|
TGEN
3950
CALL
Tecogen Inc
TGEN
$89.2M
| $263K | ﹤0.01% |
53,300
-8,700
| -14% | -$65.3K |
|
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.