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 |
NVIDIA
NVDA
|
+$172M |
| 2 |
Apple
AAPL
|
+$156M |
| 3 |
Broadcom
AVGO
|
+$101M |
| 4 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$57.2M |
| 5 |
UnitedHealth
UNH
|
+$55.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$140M |
| 2 |
Amazon
AMZN
|
+$47.9M |
| 3 |
Netflix
NFLX
|
+$38.3M |
| 4 |
TSMC
TSM
|
+$37.3M |
| 5 |
Pfizer
PFE
|
+$36.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.74% |
| 2 | Communication Services | 0.19% |
| 3 | Consumer Discretionary | 0.18% |
| 4 | Healthcare | 0.17% |
| 5 | Financials | 0.14% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
8151
KT
KT
$8.84B
| $2K | ﹤0.01% |
132
+129
| +4,300% | +$2.45K |
|
8152
Key Tronic
KTCC
$40.3M
| $2K | ﹤0.01% |
+1,021
| New | +$2.71K |
|
8153
CALL
Laser Photonics
LASE
$54.2M
| $2K | ﹤0.01% |
900
-7,700
| -90% | -$20.2K |
|
8154
CALL
Leslie's
LESL
$11.6M
| $2K | ﹤0.01% |
+250
| New | +$3.29K |
|
|
8155
Leslie's
LESL
$11.6M
| $2K | ﹤0.01% |
314
-449
| -59% | -$5.91K |
|
8156
PUT
Lincoln Educational Services
LINC
$1.29B
| $2K | ﹤0.01% |
100
-4,000
| -98% | -$80.2K |
|
8157
Pulmonx
LUNG
$49.4M
| $2K | ﹤0.01% |
1,114
-13,055
| -92% | -$51.5K |
|
8158
Lyell Immunopharma
LYEL
$309M
| $2K | ﹤0.01% |
298
+248
| +496% | +$2.26K |
|
|
8159
PUT
Lyell Immunopharma
LYEL
$309M
| $2K | ﹤0.01% |
+300
| New | +$2.73K |
|
8160
MetroCity Bankshares
MCBS
$1.05B
| $2K | ﹤0.01% |
+80
| New | +$2.22K |
|
|
8161
PUT
MetroCity Bankshares
MCBS
$1.05B
| $2K | ﹤0.01% |
+100
| New | +$2.77K |
|
8162
PUT
Matthews China Innovators Active ETF
MCHS
$20.6M
| $2K | ﹤0.01% |
+100
| New | +$2.75K |
|
8163
PUT
Mizuho Financial
MFG
$129B
| $2K | ﹤0.01% |
+500
| New | +$2.59K |
|
8164
PUT
Medallion Financial
MFIN
$226M
| $2K | ﹤0.01% |
300
-4,400
| -94% | -$39.9K |
|
8165
MoneyHero
MNY
$42.3M
| $2K | ﹤0.01% |
3,636
-2,594
| -42% | -$1.95K |
|
|
8166
PUT
MoneyHero
MNY
$42.3M
| $2K | ﹤0.01% |
3,300
| – | – |
|
|
NFGC
8167
PUT
New Found Gold
NFGC
$534M
| $2K | ﹤0.01% |
1,800
-2,200
| -55% | -$2.84K |
|
8168
PUT
Natural Health Trends
NHTC
$15.4M
| $2K | ﹤0.01% |
500
+100
| +25% | +$480 |
|
8169
CALL
Nerdy
NRDY
$107M
| $2K | ﹤0.01% |
1,800
-300
| -14% | -$479 |
|
8170
NRX Pharmaceuticals
NRXP
$161M
| $2K | ﹤0.01% |
690
+57
| +9% | +$143 |
|
8171
Insperity
NSP
$1.85B
| $2K | ﹤0.01% |
42
-137
| -77% | -$9.57K |
|
8172
Bank of N.T. Butterfield & Son
NTB
$2.42B
| $2K | ﹤0.01% |
+63
| New | +$2.58K |
|
8173
PUT
NETSCOUT
NTCT
$2.86B
| $2K | ﹤0.01% |
100
-700
| -88% | -$15.6K |
|
8174
CALL
Nu Skin
NUS
$247M
| $2K | ﹤0.01% |
300
-1,100
| -79% | -$7.72K |
|
|
NVX
8175
NOVONIX
NVX
$102M
| $2K | ﹤0.01% |
+2,193
| New | +$2.52K |
|
Similar funds
Simplex Trading's Q2 2025 Portfolio in Review
As of Q2 2025, Simplex Trading held 10,048 positions worth $175B, up 12% from $156B the previous quarter. Its ten largest holdings account for 47% of the portfolio.
Simplex Trading withdrew a net $10.5B in Q2 2025, closing 1,431 positions and reducing 3,590 holdings. Its most notable exit was Constellation Energy, an estimated $35.8M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.74% of assets, up from 0.41% a quarter earlier, followed by Communication Services and Consumer Discretionary.
Against the trend, Simplex Trading opened a new position in State Street SPDR S&P 500 ETF Trust worth $61.9M.
- Simplex Trading's largest Q2 2025 buy was State Street SPDR S&P 500 ETF Trust: 100,129 shares worth $61.9M.
- Simplex Trading added most to NVIDIA in Q2 2025, an estimated $172M increase.
- Simplex Trading's biggest Q2 2025 reduction was iShares 20+ Year Treasury Bond ETF, cutting an estimated $140M.
- Simplex Trading fully exited Constellation Energy in Q2 2025, selling an estimated $35.8M.
- Simplex Trading's ten largest holdings make up 47% of its $175B portfolio in Q2 2025.
- Simplex Trading opened 1,525 new positions and closed 1,431 in Q2 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $175B.
Based on Simplex Trading's 13F filing for Q2 2025, filed 5 Aug 2025.