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 |
iShares Russell 2000 ETF
IWM
|
+$146M |
| 2 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$108M |
| 3 |
Apple
AAPL
|
+$62.9M |
| 4 |
Tesla
TSLA
|
+$51.9M |
| 5 |
Micron Technology
MU
|
+$39.5M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$108M |
| 2 |
Meta Platforms (Facebook)
META
|
+$104M |
| 3 |
Advanced Micro Devices
AMD
|
+$92.1M |
| 4 |
Amazon
AMZN
|
+$90.3M |
| 5 |
TSMC
TSM
|
+$82.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 98.28% |
| 2 | Technology | 0.76% |
| 3 | Consumer Discretionary | 0.21% |
| 4 | Communication Services | 0.19% |
| 5 | Healthcare | 0.15% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
1226
PUT
Las Vegas Sands
LVS
$25.3B
| $4.86M | ﹤0.01% |
105,200
-84,500
| -45% | -$4.38M |
|
1227
PUT
MetLife
MET
$62.1B
| $4.85M | ﹤0.01% |
57,300
-6,000
| -9% | -$484K |
|
1228
CALL
Shoals Technologies Group
SHLS
$1.26B
| $4.85M | ﹤0.01% |
489,700
+48,000
| +11% | +$436K |
|
1229
CALL
ArcelorMittal
MT
$53.2B
| $4.85M | ﹤0.01% |
80,500
+1,100
| +1% | +$68.8K |
|
1230
PUT
Alaska Air
ALK
$4.57B
| $4.84M | ﹤0.01% |
92,800
-89,400
| -49% | -$3.82M |
|
1231
Astera Labs
ALAB
$63.3B
| $4.83M | ﹤0.01% |
10,006
-81,860
| -89% | -$21.7M |
|
1232
PUT
Suncor Energy
SU
$79.8B
| $4.83M | ﹤0.01% |
90,000
-15,800
| -15% | -$1M |
|
|
DFTX
1233
PUT
Definium Therapeutics
DFTX
$4.86B
| $4.83M | ﹤0.01% |
102,700
+33,600
| +49% | +$830K |
|
1234
CALL
Kymera Therapeutics
KYMR
$9.31B
| $4.83M | ﹤0.01% |
42,100
+26,600
| +172% | +$2.29M |
|
1235
CALL
BioMarin Pharmaceuticals
BMRN
$11.7B
| $4.82M | ﹤0.01% |
84,300
+27,300
| +48% | +$1.5M |
|
1236
CALL
Keurig Dr Pepper
KDP
$43.5B
| $4.82M | ﹤0.01% |
147,300
-4,500
| -3% | -$131K |
|
1237
CALL
Fastly Inc
FSLY
$3.98B
| $4.82M | ﹤0.01% |
262,400
+40,500
| +18% | +$880K |
|
1238
PUT
CRH
CRH
$56.6B
| $4.82M | ﹤0.01% |
45,000
-1,700
| -4% | -$187K |
|
1239
Axsome Therapeutics
AXSM
$10.2B
| $4.81M | ﹤0.01% |
+19,643
| New | +$4.26M |
|
1240
CALL
Insmed
INSM
$25.7B
| $4.8M | ﹤0.01% |
45,000
+26,300
| +141% | +$3.18M |
|
1241
PUT
NetApp
NTAP
$39.5B
| $4.8M | ﹤0.01% |
31,000
+12,600
| +68% | +$1.65M |
|
1242
PUT
SiTime
SITM
$19.9B
| $4.77M | ﹤0.01% |
6,400
+5,800
| +967% | +$3.66M |
|
1243
CALL
Dover
DOV
$25.8B
| $4.75M | ﹤0.01% |
21,200
+19,800
| +1,414% | +$4.31M |
|
1244
Under Armour
UAA
$1.9B
| $4.74M | ﹤0.01% |
741,338
-155,703
| -17% | -$923K |
|
1245
PUT
Align Technology
ALGN
$10.4B
| $4.72M | ﹤0.01% |
28,000
-800
| -3% | -$139K |
|
1246
CALL
Expedia Group
EXPE
$31.7B
| $4.71M | ﹤0.01% |
18,400
-800
| -4% | -$190K |
|
1247
PUT
Blue Owl Capital
OWL
$6.37B
| $4.7M | ﹤0.01% |
536,600
-835,300
| -61% | -$7.94M |
|
1248
CALL
Boston Properties
BXP
$10.1B
| $4.69M | ﹤0.01% |
70,800
+48,700
| +220% | +$2.91M |
|
1249
CALL
Cintas
CTAS
$79.9B
| $4.69M | ﹤0.01% |
27,600
+16,900
| +158% | +$2.92M |
|
1250
PUT
Sphere Entertainment
SPHR
$5.07B
| $4.69M | ﹤0.01% |
27,100
+7,800
| +40% | +$1.09M |
|
Similar funds
Simplex Trading's Q2 2026 Portfolio in Review
As of Q2 2026, Simplex Trading held 10,638 positions worth $171B, up 14% from $149B the previous quarter. Its ten largest holdings account for 50% of the portfolio.
Simplex Trading's Q2 2026 filing shows 1,714 new, 3,712 increased, 3,486 reduced and 1,487 closed positions. Its largest new stake was Micron Technology: 52,682 shares worth $60.8M. The largest sale was State Street SPDR S&P 500 ETF Trust, an estimated $108M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, down from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- Simplex Trading's largest Q2 2026 buy was Micron Technology: 52,682 shares worth $60.8M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q2 2026, an estimated $146M increase.
- Simplex Trading's biggest Q2 2026 reduction was State Street SPDR S&P 500 ETF Trust, cutting an estimated $108M.
- Simplex Trading fully exited Intel in Q2 2026, selling an estimated $76.6M.
- Simplex Trading's ten largest holdings make up 50% of its $171B portfolio in Q2 2026.
- Simplex Trading opened 1,714 new positions and closed 1,487 in Q2 2026.
- Simplex Trading's portfolio value rose 14% quarter-over-quarter to $171B.
Based on Simplex Trading's 13F filing for Q2 2026, filed 12 Aug 2026.