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 |
NVIDIA
NVDA
|
+$172M |
| 2 |
Apple
AAPL
|
+$156M |
| 3 |
Broadcom
AVGO
|
+$101M |
| 4 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$57.2M |
| 5 |
UnitedHealth
UNH
|
+$55.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$140M |
| 2 |
Amazon
AMZN
|
+$47.9M |
| 3 |
Netflix
NFLX
|
+$38.3M |
| 4 |
TSMC
TSM
|
+$37.3M |
| 5 |
Pfizer
PFE
|
+$36.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.74% |
| 2 | Communication Services | 0.19% |
| 3 | Consumer Discretionary | 0.18% |
| 4 | Healthcare | 0.17% |
| 5 | Financials | 0.14% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
5451
PUT
Hayward Holdings
HAYW
$3.24B
| $80K | ﹤0.01% |
5,800
+5,700
| +5,700% | +$76.8K |
|
5452
Resources Connection
RGP
$151M
| $80K | ﹤0.01% |
15,049
+14,819
| +6,443% | +$80.4K |
|
5453
PUT
Seanergy Maritime Holdings
SHIP
$381M
| $80K | ﹤0.01% |
12,800
+3,900
| +44% | +$23.5K |
|
5454
Sterling Infrastructure
STRL
$18.6B
| $80K | ﹤0.01% |
349
-4,452
| -93% | -$777K |
|
5455
Valmont Industries
VMI
$9.34B
| $80K | ﹤0.01% |
245
-52
| -18% | -$15.9K |
|
5456
Zymeworks
ZYME
$1.61B
| $80K | ﹤0.01% |
6,445
+2,277
| +55% | +$27.1K |
|
5457
PUT
Flywire
FLYW
$1.98B
| $79K | ﹤0.01% |
6,800
-9,400
| -58% | -$95.7K |
|
5458
CALL
Geospace Technologies
GEOS
$93.4M
| $79K | ﹤0.01% |
5,600
+5,100
| +1,020% | +$38.1K |
|
5459
CALL
El Pollo Loco
LOCO
$501M
| $79K | ﹤0.01% |
7,200
+6,900
| +2,300% | +$68.4K |
|
5460
CALL
Phreesia
PHR
$664M
| $79K | ﹤0.01% |
2,800
-4,600
| -62% | -$117K |
|
5461
Ribbon Communications
RBBN
$384M
| $79K | ﹤0.01% |
19,880
+18,687
| +1,566% | +$67.4K |
|
5462
CALL
Avita Medical
RCEL
$133M
| $79K | ﹤0.01% |
+15,000
| New | +$109K |
|
5463
PUT
SES AI
SES
$203M
| $79K | ﹤0.01% |
89,800
+81,600
| +995% | +$68.5K |
|
5464
CALL
VirTra
VTSI
$34.8M
| $79K | ﹤0.01% |
11,300
+6,200
| +122% | +$32.6K |
|
5465
PUT
Arcosa
ACA
$7.13B
| $78K | ﹤0.01% |
900
| – | – |
|
5466
CALL
Mission Produce
AVO
$1.11B
| $78K | ﹤0.01% |
6,700
-7,800
| -54% | -$84.5K |
|
|
AZUL
5467
PUT
DELISTED
Azul
AZUL
| $78K | ﹤0.01% |
156,400
-110,000
| -41% | -$113K |
|
5468
CALL
Compass Minerals
CMP
$1.24B
| $78K | ﹤0.01% |
3,900
-16,500
| -81% | -$267K |
|
5469
PUT
Cousins Properties
CUZ
$5.24B
| $78K | ﹤0.01% |
2,600
-100
| -4% | -$2.82K |
|
|
5470
CALL
Flywire
FLYW
$1.98B
| $78K | ﹤0.01% |
6,700
-700
| -9% | -$7.13K |
|
5471
PUT
Gran Tierra Energy
GTE
$262M
| $78K | ﹤0.01% |
16,500
| – | – |
|
5472
CALL
Janux Therapeutics
JANX
$918M
| $78K | ﹤0.01% |
3,400
+600
| +21% | +$15.8K |
|
5473
PUT
Manhattan Associates
MANH
$11.1B
| $78K | ﹤0.01% |
400
+200
| +100% | +$36.3K |
|
5474
Myriad Genetics
MYGN
$267M
| $78K | ﹤0.01% |
14,791
+13,516
| +1,060% | +$79.8K |
|
5475
CALL
Payoneer
PAYO
$2.42B
| $78K | ﹤0.01% |
11,400
-2,700
| -19% | -$18.3K |
|
Similar funds
Simplex Trading's Q2 2025 Portfolio in Review
As of Q2 2025, Simplex Trading held 10,048 positions worth $175B, up 12% from $156B the previous quarter. Its ten largest holdings account for 47% of the portfolio.
Simplex Trading withdrew a net $10.5B in Q2 2025, closing 1,431 positions and reducing 3,590 holdings. Its most notable exit was Constellation Energy, an estimated $35.8M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.74% of assets, up from 0.41% a quarter earlier, followed by Communication Services and Consumer Discretionary.
Against the trend, Simplex Trading opened a new position in State Street SPDR S&P 500 ETF Trust worth $61.9M.
- Simplex Trading's largest Q2 2025 buy was State Street SPDR S&P 500 ETF Trust: 100,129 shares worth $61.9M.
- Simplex Trading added most to NVIDIA in Q2 2025, an estimated $172M increase.
- Simplex Trading's biggest Q2 2025 reduction was iShares 20+ Year Treasury Bond ETF, cutting an estimated $140M.
- Simplex Trading fully exited Constellation Energy in Q2 2025, selling an estimated $35.8M.
- Simplex Trading's ten largest holdings make up 47% of its $175B portfolio in Q2 2025.
- Simplex Trading opened 1,525 new positions and closed 1,431 in Q2 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $175B.
Based on Simplex Trading's 13F filing for Q2 2025, filed 5 Aug 2025.