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 | |
|---|---|---|---|---|---|---|
3526
CALL
Upexi
UPXI
$64.7M
| $398K | ﹤0.01% |
236,700
-336,600
| -59% | -$1.27M |
|
3527
CALL
Vir Biotechnology
VIR
$1.49B
| $397K | ﹤0.01% |
65,900
+51,700
| +364% | +$308K |
|
3528
Direxion Daily NYSE FANG+ Bull 2X ETF
FNGG
$115M
| $397K | ﹤0.01% |
1,926
+1,340
| +229% | +$321K |
|
3529
CALL
ScottsMiracle-Gro
SMG
$4.25B
| $397K | ﹤0.01% |
6,800
-3,500
| -34% | -$196K |
|
3530
CALL
Bank of Hawaii
BOH
$3.17B
| $397K | ﹤0.01% |
5,800
+100
| +2% | +$6.59K |
|
|
KC
3531
CALL
Kingsoft Cloud Holdings
KC
$3.03B
| $396K | ﹤0.01% |
38,300
-6,400
| -14% | -$78.6K |
|
3532
CALL
AppFolio
APPF
$6.31B
| $396K | ﹤0.01% |
+1,700
| New | +$404K |
|
3533
CALL
Eastern Bankshares
EBC
$5.39B
| $394K | ﹤0.01% |
21,400
+19,500
| +1,026% | +$357K |
|
3534
CALL
Absci
ABSI
$1.21B
| $394K | ﹤0.01% |
113,000
+15,700
| +16% | +$57.2K |
|
3535
CALL
Sabre
SABR
$743M
| $394K | ﹤0.01% |
289,400
-27,300
| -9% | -$47K |
|
3536
CALL
Vanguard FTSE Developed Markets ETF
VEA
$225B
| $394K | ﹤0.01% |
6,300
+3,700
| +142% | +$227K |
|
3537
National Grid
NGG
$81.3B
| $393K | ﹤0.01% |
5,083
-6,676
| -57% | -$502K |
|
|
FLY
3538
Firefly Aerospace
FLY
$3.17B
| $392K | ﹤0.01% |
17,531
-26,860
| -61% | -$622K |
|
3539
PUT
Matthews International
MATW
$900M
| $392K | ﹤0.01% |
15,000
-8,000
| -35% | -$196K |
|
3540
Jacobs Solutions
J
$16.6B
| $392K | ﹤0.01% |
+2,957
| New | +$434K |
|
3541
Lufax Holding
LU
$1.33B
| $391K | ﹤0.01% |
152,713
-159,797
| -51% | -$472K |
|
3542
CALL
WEC Energy
WEC
$37B
| $390K | ﹤0.01% |
3,700
-2,300
| -38% | -$255K |
|
3543
Kemper
KMPR
$1.82B
| $390K | ﹤0.01% |
+9,614
| New | +$412K |
|
3544
Graphic Packaging
GPK
$3.45B
| $389K | ﹤0.01% |
25,846
+21,456
| +489% | +$353K |
|
3545
Ligand Pharmaceuticals
LGND
$5.94B
| $389K | ﹤0.01% |
2,055
+408
| +25% | +$78.4K |
|
3546
SiTime
SITM
$14.7B
| $389K | ﹤0.01% |
1,100
+88
| +9% | +$27.5K |
|
|
RDTL
3547
GraniteShares 2x Long RDDT Daily ETF
RDTL
$44.9M
| $388K | ﹤0.01% |
+7,735
| New | +$346K |
|
3548
CALL
Old Republic International
ORI
$10.8B
| $388K | ﹤0.01% |
8,500
-7,500
| -47% | -$326K |
|
3549
PUT
Coursera
COUR
$1.68B
| $388K | ﹤0.01% |
52,700
-29,800
| -36% | -$260K |
|
3550
CALL
Orion
OEC
$400M
| $388K | ﹤0.01% |
73,400
+16,700
| +29% | +$90.6K |
|
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.