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 |
Microsoft
MSFT
|
+$234M |
| 2 |
iShares Russell 2000 ETF
IWM
|
+$97.5M |
| 3 |
Amazon
AMZN
|
+$96.8M |
| 4 |
iShares Bitcoin Trust
IBIT
|
+$80.6M |
| 5 |
Pinduoduo
PDD
|
+$54.9M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$129M |
| 2 |
Alphabet (Google) Class A
GOOGL
|
+$92.9M |
| 3 |
Broadcom
AVGO
|
+$82.9M |
| 4 |
Alphabet (Google) Class C
GOOG
|
+$68.4M |
| 5 |
Meta Platforms (Facebook)
META
|
+$59.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.79% |
| 2 | Consumer Discretionary | 0.3% |
| 3 | Healthcare | 0.25% |
| 4 | Financials | 0.17% |
| 5 | Industrials | 0.09% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
|
UWC
101
PUT
DELISTED
PROSHARES TR ULTRA RUSSELL3000
UWC
| $177M | 0.09% |
1,695,700
+774,200
| +84% | +$80.9M |
|
102
PUT
Boeing
BA
$163B
| $177M | 0.09% |
893,100
-716,400
| -45% | -$162M |
|
103
CALL
Goldman Sachs
GS
$323B
| $177M | 0.09% |
222,100
-113,600
| -34% | -$84.2M |
|
104
PUT
Costco
COST
$409B
| $176M | 0.09% |
197,700
-42,600
| -18% | -$40.8M |
|
105
CALL
Arm
ARM
$306B
| $176M | 0.09% |
1,241,600
+229,800
| +23% | +$33.5M |
|
106
CALL
JD.com
JD
$40.9B
| $174M | 0.09% |
4,986,700
+2,618,800
| +111% | +$85.3M |
|
107
CALL
Adobe
ADBE
$88B
| $174M | 0.09% |
494,200
+286,100
| +137% | +$103M |
|
108
CALL
Cisco
CSCO
$445B
| $174M | 0.09% |
2,546,800
+108,700
| +4% | +$7.41M |
|
109
PUT
CrowdStrike
CRWD
$191B
| $174M | 0.09% |
1,683,600
+1,200
| +0.1% | +$136K |
|
110
PUT
Carvana
CVNA
$45.6B
| $173M | 0.09% |
2,297,000
-1,204,000
| -34% | -$86.1M |
|
111
CALL
Palo Alto Networks
PANW
$273B
| $172M | 0.09% |
847,000
+191,400
| +29% | +$36.6M |
|
112
PUT
Reddit
RDDT
$32.5B
| $172M | 0.09% |
746,700
+342,400
| +85% | +$69.9M |
|
113
CALL
Iris Energy
IREN
$15.3B
| $170M | 0.09% |
3,632,500
+49,100
| +1% | +$1.19M |
|
114
PUT
Booking.com
BKNG
$139B
| $170M | 0.09% |
785,000
-1,317,500
| -63% | -$294M |
|
115
PUT
Bloom Energy
BE
$65B
| $168M | 0.09% |
1,992,200
+1,321,000
| +197% | +$61.3M |
|
116
PUT
Super Micro Computer
SMCI
$20.5B
| $168M | 0.09% |
3,629,700
+281,400
| +8% | +$13.4M |
|
117
CALL
Walt Disney
DIS
$168B
| $168M | 0.09% |
1,466,300
-101,700
| -6% | -$12M |
|
|
ETHA
118
CALL
iShares Ethereum Trust ETF
ETHA
$5.48B
| $167M | 0.09% |
5,315,100
+4,532,500
| +579% | +$134M |
|
119
CALL
ExxonMobil
XOM
$636B
| $165M | 0.08% |
1,525,000
-455,900
| -23% | -$50.7M |
|
|
120
CALL
Super Micro Computer
SMCI
$20.5B
| $165M | 0.08% |
3,440,300
-2,749,400
| -44% | -$131M |
|
121
PUT
Uber
UBER
$144B
| $164M | 0.08% |
1,771,500
-465,300
| -21% | -$43.5M |
|
122
CALL
Baidu
BIDU
$36.7B
| $164M | 0.08% |
1,244,900
+477,800
| +62% | +$47.3M |
|
123
CALL
Lucid Motors
LCID
$2.84B
| $164M | 0.08% |
6,878,800
+6,498,170
| +1,707% | +$147M |
|
124
CALL
SoFi Technologies
SOFI
$22.2B
| $163M | 0.08% |
6,155,400
+1,123,400
| +22% | +$26.7M |
|
|
125
PUT
Arm
ARM
$306B
| $162M | 0.08% |
1,318,500
+202,100
| +18% | +$29.4M |
|
Similar funds
Simplex Trading's Q3 2025 Portfolio in Review
As of Q3 2025, Simplex Trading held 10,358 positions worth $195B, up 12% from $175B the previous quarter. Its ten largest holdings account for 46% of the portfolio.
Simplex Trading's Q3 2025 filing shows 1,743 new, 3,828 increased, 3,250 reduced and 1,308 closed positions. Its largest new stake was Microsoft: 458,309 shares worth $237M. The largest sale was iShares 20+ Year Treasury Bond ETF, an estimated $129M.
By sector, the portfolio is most concentrated in Technology at 0.79% of assets, up from 0.74% a quarter earlier, followed by Consumer Discretionary and Healthcare.
- Simplex Trading's largest Q3 2025 buy was Microsoft: 458,309 shares worth $237M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q3 2025, an estimated $97.5M increase.
- Simplex Trading's biggest Q3 2025 reduction was Alphabet (Google) Class A, cutting an estimated $92.9M.
- Simplex Trading fully exited iShares 20+ Year Treasury Bond ETF in Q3 2025, selling an estimated $129M.
- Simplex Trading's ten largest holdings make up 46% of its $195B portfolio in Q3 2025.
- Simplex Trading opened 1,743 new positions and closed 1,308 in Q3 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $195B.
Based on Simplex Trading's 13F filing for Q3 2025, filed 12 Nov 2025.