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 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$272M |
| 2 |
Alphabet (Google) Class A
GOOGL
|
+$99M |
| 3 |
NVIDIA
NVDA
|
+$89.9M |
| 4 |
TSMC
TSM
|
+$87.7M |
| 5 |
Amazon
AMZN
|
+$61M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Apple
AAPL
|
+$518M |
| 2 |
Strategy Inc
MSTR
|
+$81.2M |
| 3 |
Alibaba
BABA
|
+$66.7M |
| 4 |
Advanced Micro Devices
AMD
|
+$44.3M |
| 5 |
Uber
UBER
|
+$41.3M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.41% |
| 2 | Consumer Discretionary | 0.22% |
| 3 | Healthcare | 0.17% |
| 4 | Communication Services | 0.15% |
| 5 | Financials | 0.13% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
8126
PUT
Afya
AFYA
$1.27B
| $1K | ﹤0.01% |
100
| – | – |
|
8127
CALL
Airgain
AIRG
$74.3M
| $1K | ﹤0.01% |
500
| – | – |
|
|
ALLK
8128
DELISTED
Allakos
ALLK
| $1K | ﹤0.01% |
8,016
-128,832
| -94% | -$58.2K |
|
8129
Allient
ALNT
$1.47B
| $1K | ﹤0.01% |
+48
| New | +$1.19K |
|
8130
PUT
Annexon
ANNX
$855M
| $1K | ﹤0.01% |
800
-14,900
| -95% | -$49.6K |
|
8131
CALL
Sphere 3D
ANY
$14.6M
| $1K | ﹤0.01% |
460
-11,600
| -96% | -$85.9K |
|
8132
PUT
Apyx Medical
APYX
$165M
| $1K | ﹤0.01% |
1,000
-4,500
| -82% | -$6.2K |
|
8133
CALL
Aqua Metals
AQMS
$9.63M
| $1K | ﹤0.01% |
+90
| New | +$1.85K |
|
|
8134
PUT
Aqua Metals
AQMS
$9.63M
| $1K | ﹤0.01% |
100
-50
| -33% | -$1.03K |
|
|
ARBK
8135
PUT
Argo Blockchain
ARBK
$45.5M
| $1K | ﹤0.01% |
20
-33
| -62% | -$3.39K |
|
8136
Astec Industries
ASTE
$1.3B
| $1K | ﹤0.01% |
53
-1,457
| -96% | -$50.1K |
|
8137
PUT
Atossa Therapeutics
ATOS
$22.8M
| $1K | ﹤0.01% |
+100
| New | +$1.21K |
|
8138
CALL
Aura Biosciences
AURA
$729M
| $1K | ﹤0.01% |
+200
| New | +$1.51K |
|
8139
PUT
Aveanna Healthcare
AVAH
$2.06B
| $1K | ﹤0.01% |
300
| – | – |
|
8140
PUT
Avanos Medical
AVNS
$1.17B
| $1K | ﹤0.01% |
100
-1,000
| -91% | -$15.6K |
|
|
AXDX
8141
DELISTED
Accelerate Diagnostics
AXDX
| $1K | ﹤0.01% |
1,905
+542
| +40% | +$618 |
|
8142
CALL
AXT Inc
AXTI
$3.09B
| $1K | ﹤0.01% |
1,100
-12,800
| -92% | -$24.5K |
|
8143
Belden
BDC
$4B
| $1K | ﹤0.01% |
+19
| New | +$2.11K |
|
8144
CALL
Biodesix
BDSX
$228M
| $1K | ﹤0.01% |
+370
| New | +$7.1K |
|
8145
PUT
Black Diamond Therapeutics
BDTX
$101M
| $1K | ﹤0.01% |
700
-5,700
| -89% | -$12K |
|
8146
Beam Global
BEEM
$22.4M
| $1K | ﹤0.01% |
857
-11,598
| -93% | -$29.9K |
|
|
8147
PUT
Beam Global
BEEM
$22.4M
| $1K | ﹤0.01% |
800
+100
| +14% | +$258 |
|
|
BLDP
8148
PUT
Ballard Power Systems
BLDP
$874M
| $1K | ﹤0.01% |
1,800
+800
| +80% | +$1.13K |
|
8149
CALL
Biomerica
BMRA
$4.88M
| $1K | ﹤0.01% |
+1,525
| New | +$7.54K |
|
|
BPT
8150
PUT
DELISTED
BP Prudhoe Bay Royalty Trust
BPT
| $1K | ﹤0.01% |
2,800
-4,700
| -63% | -$2.66K |
|
Similar funds
Simplex Trading's Q1 2025 Portfolio in Review
As of Q1 2025, Simplex Trading held 10,070 positions worth $156B, down 13% from $179B the previous quarter. Its ten largest holdings account for 51% of the portfolio.
Simplex Trading withdrew a net $7.93B in Q1 2025, closing 1,547 positions and reducing 3,654 holdings. Its most notable exit was Alibaba, an estimated $66.7M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.41% of assets, down from 0.68% a quarter earlier, followed by Consumer Discretionary and Healthcare.
Against the trend, Simplex Trading opened a new position in iShares 20+ Year Treasury Bond ETF worth $278M.
- Simplex Trading's largest Q1 2025 buy was iShares 20+ Year Treasury Bond ETF: 3,057,978 shares worth $278M.
- Simplex Trading added most to NVIDIA in Q1 2025, an estimated $89.9M increase.
- Simplex Trading's biggest Q1 2025 reduction was Apple, cutting an estimated $518M.
- Simplex Trading fully exited Alibaba in Q1 2025, selling an estimated $66.7M.
- Simplex Trading's ten largest holdings make up 51% of its $156B portfolio in Q1 2025.
- Simplex Trading opened 1,566 new positions and closed 1,547 in Q1 2025.
- Simplex Trading's portfolio value fell 13% quarter-over-quarter to $156B.
Based on Simplex Trading's 13F filing for Q1 2025, filed 12 May 2025.