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 | |
|---|---|---|---|---|---|---|
901
PUT
BJs Wholesale Club
BJ
$11.7B
| $9.23M | 0.01% |
102,500
-500
| -0.5% | -$45.9K |
|
902
Oscar Health
OSCR
$8.72B
| $9.19M | 0.01% |
639,236
+218,403
| +52% | +$3.78M |
|
903
CALL
NexGen Energy
NXE
$6.2B
| $9.18M | 0.01% |
997,300
+541,000
| +119% | +$4.78M |
|
904
Abercrombie & Fitch
ANF
$4.04B
| $9.12M | 0.01% |
+72,486
| New | +$6.34M |
|
905
PUT
Monster Beverage
MNST
$91.5B
| $9.12M | 0.01% |
119,000
+40,100
| +51% | +$2.87M |
|
|
TIGR
906
CALL
UP Fintech Holding
TIGR
$870M
| $9.1M | 0.01% |
951,800
+73,800
| +8% | +$705K |
|
907
PUT
BHP
BHP
$212B
| $9.1M | 0.01% |
150,700
-5,800
| -4% | -$330K |
|
908
XPeng
XPEV
$12.2B
| $9.08M | 0.01% |
447,752
+222,785
| +99% | +$4.83M |
|
|
EXK
909
CALL
Endeavour Silver
EXK
$2.34B
| $9.08M | 0.01% |
966,000
+289,300
| +43% | +$2.45M |
|
|
CDTX
910
PUT
DELISTED
Cidara Therapeutics
CDTX
| $9.08M | 0.01% |
41,100
+13,500
| +49% | +$2.18M |
|
911
CALL
NuScale Power
SMR
$3.05B
| $9.07M | 0.01% |
639,900
+30,700
| +5% | +$878K |
|
|
CRCL
912
Circle Internet Group
CRCL
$15.5B
| $9.06M | 0.01% |
+114,194
| New | +$11.8M |
|
913
PUT
Shell
SHEL
$243B
| $9.05M | 0.01% |
123,100
-30,100
| -20% | -$2.22M |
|
914
PUT
Stellantis
STLA
$16.7B
| $9.02M | 0.01% |
828,100
-5,300
| -0.6% | -$57K |
|
915
CALL
HCA Healthcare
HCA
$83.5B
| $8.96M | 0.01% |
19,200
-12,600
| -40% | -$5.85M |
|
916
CALL
Ares Management
ARES
$27.4B
| $8.95M | 0.01% |
55,400
+21,600
| +64% | +$3.36M |
|
917
PUT
Nutrien
NTR
$32.9B
| $8.95M | 0.01% |
145,000
-800
| -0.5% | -$47.1K |
|
918
CALL
Centrus Energy
LEU
$3.36B
| $8.93M | 0.01% |
36,800
-31,000
| -46% | -$9.36M |
|
919
CALL
Zoetis
ZTS
$31.3B
| $8.92M | 0.01% |
70,900
+36,500
| +106% | +$4.76M |
|
920
PUT
Global Payments
GPN
$21.3B
| $8.9M | 0.01% |
115,000
-23,100
| -17% | -$1.86M |
|
921
CALL
Gildan
GIL
$9.18B
| $8.9M | 0.01% |
142,500
+140,700
| +7,817% | +$8.36M |
|
922
CALL
Bilibili
BILI
$7.32B
| $8.89M | 0.01% |
361,400
-375,300
| -51% | -$10.1M |
|
923
CALL
Cencora
COR
$59.4B
| $8.88M | 0.01% |
26,300
-16,000
| -38% | -$5.45M |
|
924
PUT
Conagra Brands
CAG
$6.88B
| $8.87M | 0.01% |
512,600
+91,900
| +22% | +$1.63M |
|
925
CALL
NRG Energy
NRG
$30.2B
| $8.82M | 0.01% |
55,400
-63,100
| -53% | -$10.4M |
|
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.