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 | |
|---|---|---|---|---|---|---|
1476
PUT
Polaris
PII
$4.15B
| $3.87M | ﹤0.01% |
61,200
+23,900
| +64% | +$1.57M |
|
1477
Goodyear
GT
$2.07B
| $3.87M | ﹤0.01% |
441,421
+53,781
| +14% | +$424K |
|
1478
CALL
Teladoc Health
TDOC
$1.58B
| $3.86M | ﹤0.01% |
551,800
-41,700
| -7% | -$326K |
|
1479
PUT
NetApp
NTAP
$32.9B
| $3.86M | ﹤0.01% |
36,000
+1,800
| +5% | +$206K |
|
1480
CALL
Henry Schein
HSIC
$9.74B
| $3.85M | ﹤0.01% |
51,000
+19,900
| +64% | +$1.4M |
|
1481
PUT
Elanco Animal Health
ELAN
$12.4B
| $3.85M | ﹤0.01% |
170,100
+147,400
| +649% | +$3.21M |
|
|
SEE
1482
CALL
DELISTED
Sealed Air
SEE
| $3.85M | ﹤0.01% |
92,900
+66,800
| +256% | +$2.58M |
|
|
PRMB
1483
PUT
Primo Brands
PRMB
$8.24B
| $3.83M | ﹤0.01% |
234,400
+213,700
| +1,032% | +$3.95M |
|
1484
PUT
C3.ai
AI
$1.27B
| $3.82M | ﹤0.01% |
283,700
-196,400
| -41% | -$3.13M |
|
1485
PUT
Dominion Energy
D
$62.5B
| $3.82M | ﹤0.01% |
65,200
+26,800
| +70% | +$1.61M |
|
1486
PUT
Cheniere Energy
LNG
$56.5B
| $3.81M | ﹤0.01% |
19,600
-19,700
| -50% | -$4.14M |
|
1487
Corcept Therapeutics
CORT
$10.2B
| $3.8M | ﹤0.01% |
+109,337
| New | +$8.59M |
|
1488
CALL
Paychex
PAYX
$40.4B
| $3.8M | ﹤0.01% |
33,900
-15,800
| -32% | -$1.85M |
|
1489
PUT
Molina Healthcare
MOH
$10.3B
| $3.8M | ﹤0.01% |
21,900
+12,100
| +123% | +$1.99M |
|
1490
CALL
Arbor Realty Trust
ABR
$960M
| $3.78M | ﹤0.01% |
486,600
-232,700
| -32% | -$2.28M |
|
1491
Applied Materials
AMAT
$426B
| $3.76M | ﹤0.01% |
+14,631
| New | +$3.51M |
|
|
GRAL
1492
CALL
GRAIL Inc
GRAL
$2.91B
| $3.76M | ﹤0.01% |
43,900
-20,800
| -32% | -$1.8M |
|
1493
PUT
Incyte
INCY
$23.5B
| $3.75M | ﹤0.01% |
38,000
+22,400
| +144% | +$2.17M |
|
1494
PUT
Veeva Systems
VEEV
$30.3B
| $3.75M | ﹤0.01% |
16,800
+2,800
| +20% | +$743K |
|
1495
CALL
Royal Gold
RGLD
$17.1B
| $3.73M | ﹤0.01% |
16,800
-11,100
| -40% | -$2.2M |
|
|
KEEL
1496
Keel Infrastructure Corp
KEEL
$2.57B
| $3.73M | ﹤0.01% |
1,587,521
+145,524
| +10% | +$498K |
|
1497
PUT
TG Therapeutics
TGTX
$8.58B
| $3.73M | ﹤0.01% |
125,000
-30,500
| -20% | -$996K |
|
1498
Conagra Brands
CAG
$7.07B
| $3.72M | ﹤0.01% |
214,911
+103,207
| +92% | +$1.83M |
|
1499
PUT
Sprouts Farmers Market
SFM
$7.04B
| $3.71M | ﹤0.01% |
46,600
+21,300
| +84% | +$1.91M |
|
|
MPT
1500
CALL
Medical Properties Trust
MPT
$2.89B
| $3.71M | ﹤0.01% |
742,200
-680,000
| -48% | -$3.54M |
|
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.