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 | |
|---|---|---|---|---|---|---|
7251
PUT
Lightwave Logic
LWLG
$909M
| $11K | ﹤0.01% |
8,900
+2,700
| +44% | +$2.84K |
|
7252
CALL
MasterCraft Boat Holdings
MCFT
$596M
| $11K | ﹤0.01% |
600
-300
| -33% | -$5.13K |
|
7253
CALL
MDU Resources
MDU
$4.37B
| $11K | ﹤0.01% |
700
-2,700
| -79% | -$45.4K |
|
7254
Mercury Systems
MRCY
$6.18B
| $11K | ﹤0.01% |
+212
| New | +$10.3K |
|
7255
CALL
Myers Industries
MYE
$1.22B
| $11K | ﹤0.01% |
+800
| New | +$9.75K |
|
7256
CALL
Oxford Square Capital
OXSQ
$155M
| $11K | ﹤0.01% |
5,200
+3,700
| +247% | +$8.87K |
|
|
PINE
7257
CALL
Alpine Income Property Trust
PINE
$343M
| $11K | ﹤0.01% |
800
| – | – |
|
7258
Perdoceo Education
PRDO
$1.99B
| $11K | ﹤0.01% |
+354
| New | +$10.5K |
|
7259
PUT
Quad
QUAD
$448M
| $11K | ﹤0.01% |
2,000
+600
| +43% | +$3.25K |
|
7260
CALL
Radware
RDWR
$1.24B
| $11K | ﹤0.01% |
400
+200
| +100% | +$4.74K |
|
|
RPTX
7261
DELISTED
Repare Therapeutics
RPTX
| $11K | ﹤0.01% |
8,093
-4,688
| -37% | -$6.12K |
|
7262
CALL
Red Robin
RRGB
$135M
| $11K | ﹤0.01% |
1,900
-25,900
| -93% | -$100K |
|
7263
Invesco S&P 500 Equal Weight Consumer Discretionary ETF
RSPD
$312M
| $11K | ﹤0.01% |
214
+213
| +21,300% | +$10.7K |
|
7264
Revolve Group
RVLV
$1.83B
| $11K | ﹤0.01% |
587
-3,206
| -85% | -$64.9K |
|
7265
CALL
SITE Centers
SITC
$234M
| $11K | ﹤0.01% |
1,000
+700
| +233% | +$8.39K |
|
7266
PUT
Skyward Specialty Insurance
SKWD
$2.47B
| $11K | ﹤0.01% |
+200
| New | +$11.5K |
|
7267
Simulations Plus
SLP
$371M
| $11K | ﹤0.01% |
650
+604
| +1,313% | +$16.9K |
|
7268
CALL
SLR Investment Corp
SLRC
$712M
| $11K | ﹤0.01% |
700
-6,500
| -90% | -$104K |
|
|
SRDX
7269
PUT
DELISTED
Surmodics
SRDX
| $11K | ﹤0.01% |
400
-3,600
| -90% | -$104K |
|
7270
Sasol
SSL
$7.37B
| $11K | ﹤0.01% |
2,676
-8,829
| -77% | -$36.1K |
|
7271
PUT
Taboola.com
TBLA
$1.36B
| $11K | ﹤0.01% |
3,100
-400
| -11% | -$1.3K |
|
7272
PUT
Tronox
TROX
$962M
| $11K | ﹤0.01% |
2,300
+1,600
| +229% | +$8.71K |
|
|
TRUE
7273
CALL
DELISTED
TrueCar
TRUE
| $11K | ﹤0.01% |
6,200
+4,800
| +343% | +$7.33K |
|
7274
CALL
Wabash National
WNC
$525M
| $11K | ﹤0.01% |
1,100
+1,000
| +1,000% | +$9.61K |
|
7275
PUT
W&T Offshore
WTI
$506M
| $11K | ﹤0.01% |
7,200
-3,700
| -34% | -$5.46K |
|
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.