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 | Miscellaneous | 98.27% |
| 2 | Technology | 0.59% |
| 3 | Consumer Discretionary | 0.21% |
| 4 | Healthcare | 0.2% |
| 5 | Industrials | 0.18% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
751
PUT
Chewy
CHWY
$9.69B
| $12.1M | 0.01% |
365,700
-90,000
| -20% | -$3.12M |
|
752
Energy Transfer Partners
ET
$74B
| $12.1M | 0.01% |
732,464
+402,579
| +122% | +$6.7M |
|
753
CALL
NextNav
NN
$2.56B
| $12.1M | 0.01% |
725,200
-6,900
| -0.9% | -$98K |
|
754
CALL
United Rentals
URI
$62.9B
| $12.1M | 0.01% |
14,900
+600
| +4% | +$521K |
|
755
PUT
Core Scientific
CORZ
$5.75B
| $12M | 0.01% |
824,100
-549,900
| -40% | -$9.59M |
|
756
Avis
CAR
$4.9B
| $12M | 0.01% |
+93,201
| New | +$13M |
|
757
CALL
KE Holdings
BEKE
$19.8B
| $11.9M | 0.01% |
757,900
-140,300
| -16% | -$2.41M |
|
758
Morgan Stanley
MS
$342B
| $11.9M | 0.01% |
+67,226
| New | +$11.2M |
|
|
PPLT
759
CALL
abrdn Physical Platinum Shares ETF
PPLT
$2.23B
| $11.9M | 0.01% |
639,000
+113,000
| +21% | +$1.74M |
|
760
CALL
Peabody Energy
BTU
$3.52B
| $11.9M | 0.01% |
400,400
-122,500
| -23% | -$3.6M |
|
761
CALL
Prologis
PLD
$131B
| $11.8M | 0.01% |
92,500
+5,600
| +6% | +$698K |
|
762
United Parcel Service
UPS
$87B
| $11.8M | 0.01% |
+118,908
| New | +$11.1M |
|
763
3M
MMM
$86.9B
| $11.8M | 0.01% |
73,592
+5,959
| +9% | +$974K |
|
764
CALL
B2Gold
BTG
$7.41B
| $11.8M | 0.01% |
2,612,400
+1,138,500
| +77% | +$5.31M |
|
765
CALL
Joby Aviation
JOBY
$6.67B
| $11.8M | 0.01% |
891,300
-320,000
| -26% | -$4.91M |
|
766
CALL
TE Connectivity
TEL
$60.4B
| $11.8M | 0.01% |
51,700
+45,600
| +748% | +$10.5M |
|
767
PUT
Johnson Controls International
JCI
$87.8B
| $11.7M | 0.01% |
98,100
+37,000
| +61% | +$4.25M |
|
768
PUT
McKesson
MCK
$106B
| $11.7M | 0.01% |
14,300
-9,400
| -40% | -$7.67M |
|
|
ZVOL
769
PUT
Volatility Premium Plus ETF
ZVOL
$17.1M
| $11.7M | 0.01% |
367,200
-105,500
| -22% | -$1.18M |
|
770
CALL
DigitalBridge
DBRG
$2.99B
| $11.7M | 0.01% |
760,200
+387,500
| +104% | +$4.66M |
|
771
CALL
Workday
WDAY
$47.2B
| $11.6M | 0.01% |
54,200
-33,000
| -38% | -$7.5M |
|
772
Amplify Junior Silver Miners ETF
SILJ
$4.16B
| $11.6M | 0.01% |
+418,618
| New | +$10.3M |
|
773
PUT
Macy's
M
$6.06B
| $11.6M | 0.01% |
524,300
+4,600
| +0.9% | +$94.2K |
|
774
CALL
Canadian Natural Resources
CNQ
$104B
| $11.4M | 0.01% |
336,100
-53,300
| -14% | -$1.73M |
|
775
CALL
uniQure
QURE
$3.09B
| $11.4M | 0.01% |
475,300
+242,700
| +104% | +$9.37M |
|
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's Q4 2025 filing shows 1,476 new, 2,599 increased, 4,088 reduced and 2,184 closed positions. Its largest new stake was Western Digital: 341,762 shares worth $58.9M. The largest sale was NVIDIA, an estimated $262M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, up from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- 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.