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 | |
|---|---|---|---|---|---|---|
5751
PUT
Mativ Holdings
MATV
$481M
| $51K | ﹤0.01% |
8,300
+8,200
| +8,200% | +$67K |
|
5752
PUT
Mercer International
MERC
$42.3M
| $51K | ﹤0.01% |
8,400
-29,100
| -78% | -$195K |
|
5753
NewAmsterdam Pharma
NAMS
$3.25B
| $51K | ﹤0.01% |
2,528
+1,454
| +135% | +$32.3K |
|
5754
CALL
Park Hotels & Resorts
PK
$3.03B
| $51K | ﹤0.01% |
4,800
+2,800
| +140% | +$35.4K |
|
|
PSTL
5755
CALL
Postal Realty Trust
PSTL
$694M
| $51K | ﹤0.01% |
3,600
-13,500
| -79% | -$181K |
|
5756
Quantum-Si Incorporated
QSI
$155M
| $51K | ﹤0.01% |
42,909
-263,860
| -86% | -$506K |
|
5757
Real Brokerage
REAX
$349M
| $51K | ﹤0.01% |
12,765
-9,589
| -43% | -$45.5K |
|
5758
PUT
SkyWater Technology
SKYT
$1.6B
| $51K | ﹤0.01% |
7,300
-14,100
| -66% | -$138K |
|
5759
State Street SPDR Portfolio Intermediate Term Treasury ETF
SPTI
$10.4B
| $51K | ﹤0.01% |
1,791
+1,700
| +1,868% | +$47.8K |
|
5760
CALL
Stoneridge
SRI
$195M
| $51K | ﹤0.01% |
11,300
-29,600
| -72% | -$151K |
|
5761
CALL
Astronics
ATRO
$3.43B
| $50K | ﹤0.01% |
2,520
+2,040
| +425% | +$34.3K |
|
5762
CALL
Belden
BDC
$4.83B
| $50K | ﹤0.01% |
500
-800
| -62% | -$88.7K |
|
|
CCRN
5763
PUT
DELISTED
Cross Country Healthcare
CCRN
| $50K | ﹤0.01% |
3,400
+700
| +26% | +$12K |
|
5764
CALL
Cardiff Oncology
CRDF
$66.5M
| $50K | ﹤0.01% |
16,100
-92,400
| -85% | -$365K |
|
5765
PUT
Endava
DAVA
$158M
| $50K | ﹤0.01% |
2,600
-2,100
| -45% | -$58.3K |
|
|
EFC
5766
CALL
Ellington Financial
EFC
$1.67B
| $50K | ﹤0.01% |
3,800
-7,100
| -65% | -$91.8K |
|
|
FFWM
5767
DELISTED
First Foundation Inc
FFWM
| $50K | ﹤0.01% |
+9,783
| New | +$52.5K |
|
5768
PUT
FormFactor
FORM
$8.28B
| $50K | ﹤0.01% |
1,800
-1,800
| -50% | -$66.2K |
|
5769
NGL Energy Partners
NGL
$2.05B
| $50K | ﹤0.01% |
11,039
-3,468
| -24% | -$17.2K |
|
5770
CALL
Spectrum Brands
SPB
$2.04B
| $50K | ﹤0.01% |
700
-3,500
| -83% | -$275K |
|
5771
CALL
Entrada Therapeutics
TRDA
$264M
| $50K | ﹤0.01% |
5,600
+4,400
| +367% | +$54.8K |
|
5772
PUT
LendingTree
TREE
$447M
| $50K | ﹤0.01% |
1,000
-29,600
| -97% | -$1.32M |
|
5773
Sixth Street Specialty
TSLX
$1.63B
| $50K | ﹤0.01% |
+2,258
| New | +$50.3K |
|
5774
PUT
Westlake Corp
WLK
$9.03B
| $50K | ﹤0.01% |
500
-10,800
| -96% | -$1.2M |
|
5775
iShares Global Timber & Forestry ETF
WOOD
$268M
| $50K | ﹤0.01% |
669
+384
| +135% | +$30K |
|
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.