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 | |
|---|---|---|---|---|---|---|
76
PUT
Carvana
CVNA
$47B
| $198M | 0.11% |
2,346,000
+49,000
| +2% | +$3.64M |
|
77
PUT
Coinbase
COIN
$46.3B
| $195M | 0.11% |
863,600
-166,300
| -16% | -$49.6M |
|
78
CALL
CrowdStrike
CRWD
$195B
| $193M | 0.11% |
1,647,200
+38,000
| +2% | +$4.84M |
|
|
79
Apple
AAPL
$4.81T
| $193M | 0.11% |
708,741
-444,753
| -39% | -$119M |
|
80
PUT
Bank of America
BAC
$430B
| $184M | 0.1% |
3,343,800
-799,000
| -19% | -$42.2M |
|
|
KFYP
81
CALL
DELISTED
KraneShares CICC China Leaders 100 Index ETF
KFYP
| $183M | 0.1% |
5,366,400
+219,200
| +4% | +$7.46M |
|
82
CALL
Salesforce
CRM
$139B
| $181M | 0.1% |
684,300
-226,400
| -25% | -$56.3M |
|
83
CALL
Goldman Sachs
GS
$320B
| $180M | 0.1% |
204,800
-17,300
| -8% | -$14.1M |
|
84
PUT
Eli Lilly
LLY
$1.02T
| $180M | 0.1% |
167,100
-71,600
| -30% | -$68.5M |
|
85
PUT
Direxion Daily Technology Bull 3x ETF
TECL
$5.6B
| $179M | 0.1% |
3,863,000
-82,600
| -2% | -$10.6M |
|
|
86
CALL
Carvana
CVNA
$47B
| $169M | 0.1% |
2,002,000
-31,500
| -2% | -$2.34M |
|
|
87
PUT
CrowdStrike
CRWD
$195B
| $166M | 0.09% |
1,413,200
-270,400
| -16% | -$34.4M |
|
88
CALL
Iris Energy
IREN
$14.8B
| $165M | 0.09% |
4,377,800
+745,300
| +21% | +$38.4M |
|
89
CALL
Walmart Inc
WMT
$878B
| $163M | 0.09% |
1,467,400
-354,000
| -19% | -$38M |
|
90
CALL
Qualcomm
QCOM
$183B
| $162M | 0.09% |
947,100
+298,700
| +46% | +$51.2M |
|
91
CALL
iShares Morningstar Value ETF
ILCV
$1.3B
| $152M | 0.09% |
1,885,000
-857,000
| -31% | -$79.3M |
|
92
CALL
Nike
NKE
$63.7B
| $152M | 0.09% |
2,379,700
-1,013,600
| -30% | -$66.1M |
|
93
PUT
Berkshire Hathaway Class B
BRK.B
$1.06T
| $150M | 0.08% |
298,600
-18,500
| -6% | -$9.2M |
|
94
CALL
ProShares UltraPro Short QQQ
SQQQ
$1.99B
| $150M | 0.08% |
+2,236,100
| New | +$158M |
|
95
PUT
Wells Fargo
WFC
$261B
| $149M | 0.08% |
1,603,500
-111,800
| -7% | -$9.71M |
|
96
PUT
ExxonMobil
XOM
$629B
| $149M | 0.08% |
1,248,200
-106,400
| -8% | -$12.3M |
|
97
CALL
ASML
ASML
$692B
| $146M | 0.08% |
136,700
-79,200
| -37% | -$82.6M |
|
98
PUT
Booking.com
BKNG
$139B
| $146M | 0.08% |
682,500
-102,500
| -13% | -$21.1M |
|
|
99
PUT
Salesforce
CRM
$139B
| $145M | 0.08% |
549,000
+40,400
| +8% | +$10M |
|
|
100
CALL
Direxion Daily Technology Bull 3x ETF
TECL
$5.6B
| $145M | 0.08% |
2,753,800
-238,700
| -8% | -$30.5M |
|
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.