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 | |
|---|---|---|---|---|---|---|
451
CALL
McKesson
MCK
$95.3B
| $26.7M | 0.02% |
32,500
-4,300
| -12% | -$3.51M |
|
452
CALL
Royal Caribbean
RCL
$76.7B
| $26.6M | 0.02% |
95,200
-8,300
| -8% | -$2.34M |
|
453
CALL
Lumentum
LITE
$64.6B
| $26.5M | 0.02% |
72,000
+12,100
| +20% | +$3.11M |
|
454
PUT
Alcoa
AA
$12.2B
| $26.4M | 0.01% |
497,400
-103,000
| -17% | -$4.21M |
|
455
CALL
Futu Holdings
FUTU
$14.9B
| $26.4M | 0.01% |
160,900
-19,400
| -11% | -$3.33M |
|
456
PUT
Roblox
RBLX
$35.5B
| $26.4M | 0.01% |
325,900
-332,000
| -50% | -$35.2M |
|
457
PUT
TJX Companies
TJX
$172B
| $26.4M | 0.01% |
171,700
+42,300
| +33% | +$6.26M |
|
458
CALL
United Airlines
UAL
$38.1B
| $26.4M | 0.01% |
235,800
-565,900
| -71% | -$57.2M |
|
459
CALL
CAVA Group
CAVA
$7.26B
| $26.4M | 0.01% |
449,100
+75,200
| +20% | +$4.19M |
|
460
PUT
Las Vegas Sands
LVS
$30B
| $26.3M | 0.01% |
404,500
+300
| +0.1% | +$18.4K |
|
461
CALL
Devon Energy
DVN
$51.8B
| $26.3M | 0.01% |
718,200
-28,700
| -4% | -$1M |
|
462
CALL
Toronto Dominion Bank
TD
$200B
| $26.3M | 0.01% |
279,000
+33,000
| +13% | +$2.79M |
|
463
Bloom Energy
BE
$62.1B
| $26.2M | 0.01% |
301,347
+243,304
| +419% | +$25.6M |
|
|
AXON
464
PUT
Axon Enterprise
AXON
$39.6B
| $26M | 0.01% |
45,800
+7,100
| +18% | +$4.41M |
|
465
CALL
Dollar Tree
DLTR
$23.5B
| $25.9M | 0.01% |
210,800
-64,500
| -23% | -$6.91M |
|
466
PUT
EQT Corp
EQT
$33.8B
| $25.9M | 0.01% |
496,200
-52,700
| -10% | -$2.96M |
|
467
CALL
Ulta Beauty
ULTA
$20.8B
| $25.9M | 0.01% |
42,800
+8,800
| +26% | +$4.84M |
|
468
PUT
Pan American Silver
PAAS
$19.1B
| $25.8M | 0.01% |
498,900
+13,200
| +3% | +$553K |
|
469
Eos Energy Enterprises
EOSE
$1.41B
| $25.8M | 0.01% |
2,248,934
+1,045,312
| +87% | +$15M |
|
470
CALL
Kimberly-Clark
KMB
$36.1B
| $25.8M | 0.01% |
255,300
+219,000
| +603% | +$24M |
|
471
CALL
ProShares Ultra Bloomberg Natural Gas
BOIL
$422M
| $25.6M | 0.01% |
495,350
-271,400
| -35% | -$16.6M |
|
472
Oracle
ORCL
$362B
| $25.6M | 0.01% |
131,399
+107,940
| +460% | +$25.7M |
|
473
PUT
Sea Limited
SE
$64.2B
| $25.4M | 0.01% |
199,000
-90,200
| -31% | -$13.4M |
|
474
CALL
Estee Lauder
EL
$29.9B
| $25.3M | 0.01% |
241,200
-110,400
| -31% | -$10.7M |
|
|
HUT
475
PUT
Hut 8
HUT
$12.4B
| $25.2M | 0.01% |
548,400
+35,900
| +7% | +$1.58M |
|
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.