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 | |
|---|---|---|---|---|---|---|
276
PUT
Rivian
RIVN
$25B
| $53.4M | 0.03% |
3,889,200
+696,400
| +22% | +$9.45M |
|
277
CALL
Blackstone
BX
$151B
| $53.1M | 0.03% |
354,900
-123,300
| -26% | -$16.9M |
|
278
PUT
American Express
AXP
$238B
| $52.8M | 0.03% |
165,500
+30,000
| +22% | +$8.44M |
|
279
CALL
Microchip Technology
MCHP
$46.3B
| $52.5M | 0.03% |
745,800
-30,900
| -4% | -$1.7M |
|
280
PUT
KKR & Co
KKR
$85.7B
| $52.4M | 0.03% |
393,600
-24,400
| -6% | -$2.86M |
|
281
PUT
DoorDash
DASH
$77.8B
| $52.4M | 0.03% |
212,400
+41,200
| +24% | +$8.26M |
|
282
CALL
Iris Energy
IREN
$15B
| $52.2M | 0.03% |
3,583,400
+997,400
| +39% | +$8.1M |
|
|
NBIS
283
CALL
Nebius Group N.V.
NBIS
$57.5B
| $52M | 0.03% |
940,200
-329,900
| -26% | -$11.4M |
|
284
PUT
IonQ
IONQ
$13.2B
| $51.8M | 0.03% |
1,205,900
+348,000
| +41% | +$11.7M |
|
285
PUT
AbbVie
ABBV
$450B
| $51.7M | 0.03% |
278,500
-164,400
| -37% | -$30.6M |
|
286
PUT
Direxion Daily S&P Oil & Gas Exp. & Prod. Bull 2X ETF
GUSH
$254M
| $51.4M | 0.03% |
2,595,600
+104,500
| +4% | +$2.2M |
|
|
OKLO
287
PUT
Oklo
OKLO
$7.72B
| $51.3M | 0.03% |
916,100
+514,800
| +128% | +$19.9M |
|
|
SCIU
288
CALL
DELISTED
Global X Scientific Beta US ETF
SCIU
| $51.1M | 0.03% |
1,339,000
+289,300
| +28% | +$11M |
|
289
CALL
Accenture
ACN
$85.6B
| $50.8M | 0.03% |
169,900
-6,300
| -4% | -$1.92M |
|
290
PUT
Applied Materials
AMAT
$445B
| $50.3M | 0.03% |
274,600
-49,900
| -15% | -$7.91M |
|
|
291
CALL
Rivian
RIVN
$25B
| $50.2M | 0.03% |
3,653,900
-674,500
| -16% | -$9.15M |
|
292
PUT
Baidu
BIDU
$36.7B
| $50M | 0.03% |
583,000
-145,300
| -20% | -$12.5M |
|
293
PUT
McDonald's
MCD
$188B
| $49.9M | 0.03% |
203,700
-86,100
| -30% | -$26.5M |
|
|
TEM
294
CALL
Tempus AI
TEM
$8.47B
| $49.6M | 0.03% |
780,800
+219,900
| +39% | +$12.6M |
|
295
CALL
Eaton
ETN
$158B
| $49.5M | 0.03% |
138,800
-95,100
| -41% | -$29.3M |
|
296
PUT
United Airlines
UAL
$38.1B
| $49.5M | 0.03% |
760,300
-60,600
| -7% | -$4.46M |
|
297
PUT
Delta Air Lines
DAL
$55.2B
| $49.5M | 0.03% |
1,006,100
+303,200
| +43% | +$13.9M |
|
298
CALL
Caterpillar
CAT
$413B
| $49M | 0.03% |
126,200
-54,100
| -30% | -$18M |
|
|
299
PUT
Iris Energy
IREN
$15B
| $48.9M | 0.03% |
3,357,400
+625,800
| +23% | +$5.08M |
|
300
CALL
Constellation Energy
CEG
$97.7B
| $48.8M | 0.03% |
200,100
+17,800
| +10% | +$4.71M |
|
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.