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 | |
|---|---|---|---|---|---|---|
|
SERV
1526
PUT
Serve Robotics
SERV
$409M
| $3.6M | ﹤0.01% |
346,900
+18,000
| +5% | +$216K |
|
1527
Occidental Petroleum
OXY
$57B
| $3.6M | ﹤0.01% |
87,446
+72,458
| +483% | +$3.02M |
|
1528
PUT
Nice
NICE
$5.29B
| $3.59M | ﹤0.01% |
31,800
-13,200
| -29% | -$1.59M |
|
1529
PUT
Lemonade
LMND
$4.62B
| $3.59M | ﹤0.01% |
50,500
-35,000
| -41% | -$2.35M |
|
1530
CALL
Wave Life Sciences
WVE
$1.12B
| $3.58M | ﹤0.01% |
210,800
+128,800
| +157% | +$1.31M |
|
1531
CALL
Insulet
PODD
$11.3B
| $3.58M | ﹤0.01% |
12,600
+11,700
| +1,300% | +$3.66M |
|
1532
CALL
NOV
NOV
$7.45B
| $3.58M | ﹤0.01% |
229,000
+195,300
| +580% | +$2.9M |
|
1533
CALL
Hudbay
HBM
$9.92B
| $3.57M | ﹤0.01% |
180,000
-18,300
| -9% | -$309K |
|
1534
PUT
Bank OZK
OZK
$5.49B
| $3.57M | ﹤0.01% |
77,600
+33,300
| +75% | +$1.56M |
|
1535
PUT
Schwab US Broad Market ETF
SCHB
$42.8B
| $3.56M | ﹤0.01% |
127,200
+8,800
| +7% | +$229K |
|
1536
Norfolk Southern
NSC
$78.8B
| $3.56M | ﹤0.01% |
12,319
+3,407
| +38% | +$985K |
|
1537
Align Technology
ALGN
$12B
| $3.56M | ﹤0.01% |
22,776
+13,373
| +142% | +$1.92M |
|
1538
PUT
Eldorado Gold
EGO
$8.31B
| $3.55M | ﹤0.01% |
98,900
-16,900
| -15% | -$506K |
|
1539
CALL
Polestar Automotive Holding UK
PSNY
$1.98B
| $3.55M | ﹤0.01% |
166,100
+158,563
| +2,104% | +$3.31M |
|
1540
PUT
Hormel Foods
HRL
$13.9B
| $3.53M | ﹤0.01% |
149,100
+49,100
| +49% | +$1.15M |
|
1541
PUT
Zeta Global
ZETA
$4.77B
| $3.53M | ﹤0.01% |
173,400
+15,600
| +10% | +$291K |
|
1542
PUT
KeyCorp
KEY
$24.3B
| $3.52M | ﹤0.01% |
170,500
+48,800
| +40% | +$909K |
|
1543
PUT
Intellia Therapeutics
NTLA
$1.5B
| $3.51M | ﹤0.01% |
390,200
+145,900
| +60% | +$2.01M |
|
1544
Progressive
PGR
$124B
| $3.5M | ﹤0.01% |
+15,358
| New | +$3.47M |
|
1545
CALL
GDS Holdings
GDS
$6.34B
| $3.49M | ﹤0.01% |
99,900
-85,200
| -46% | -$2.95M |
|
1546
CALL
FMC
FMC
$1.42B
| $3.49M | ﹤0.01% |
251,300
+159,600
| +174% | +$3.04M |
|
1547
CALL
Bio-Rad Laboratories Class A
BIO
$8.42B
| $3.48M | ﹤0.01% |
11,500
+10,500
| +1,050% | +$3.28M |
|
1548
CALL
Agilent Technologies
A
$39.1B
| $3.48M | ﹤0.01% |
25,600
-24,500
| -49% | -$3.52M |
|
1549
Intuitive Surgical
ISRG
$121B
| $3.48M | ﹤0.01% |
6,141
-5,910
| -49% | -$3.15M |
|
1550
Vanguard Total Stock Market ETF
VTI
$654B
| $3.47M | ﹤0.01% |
+10,361
| New | +$3.45M |
|
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.