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 | |
|---|---|---|---|---|---|---|
6851
PUT
SIGA Technologies
SIGA
$240M
| $34K | ﹤0.01% |
3,800
-1,900
| -33% | -$15.2K |
|
6852
CALL
Sprout Social
SPT
$530M
| $34K | ﹤0.01% |
2,700
+1,400
| +108% | +$22.9K |
|
6853
Sasol
SSL
$7.4B
| $34K | ﹤0.01% |
5,544
+2,868
| +107% | +$16.8K |
|
6854
PUT
Teradata
TDC
$2.88B
| $34K | ﹤0.01% |
1,600
-1,800
| -53% | -$38.7K |
|
6855
CALL
Teekay
TK
$996M
| $34K | ﹤0.01% |
4,200
-99,800
| -96% | -$794K |
|
6856
CALL
Taysha Gene Therapies
TSHA
$1.61B
| $34K | ﹤0.01% |
10,500
-200
| -2% | -$566 |
|
|
TONX
6857
TON Strategy Co
TONX
$168M
| $34K | ﹤0.01% |
+4,951
| New | +$57.8K |
|
6858
PUT
Vista Gold
VGZ
$250M
| $34K | ﹤0.01% |
16,300
+13,300
| +443% | +$17.3K |
|
|
WCN
6859
Waste Connections
WCN
$43.6B
| $34K | ﹤0.01% |
199
+152
| +323% | +$27.7K |
|
6860
CALL
Select Water Solutions
WTTR
$2.22B
| $34K | ﹤0.01% |
3,200
+2,700
| +540% | +$24.7K |
|
6861
CALL
Westwater Resources
WWR
$49.7M
| $34K | ﹤0.01% |
36,700
+23,600
| +180% | +$17.7K |
|
|
YRD
6862
PUT
Yiren Digital
YRD
$93.6M
| $34K | ﹤0.01% |
5,900
+1,900
| +48% | +$11.3K |
|
|
BTCL
6863
CALL
T-Rex 2X Long Bitcoin Daily Target ETF
BTCL
$22.2M
| $34K | ﹤0.01% |
1,100
+200
| +22% | +$11.7K |
|
|
TTAM
6864
CALL
Titan America SA
TTAM
$2.94B
| $34K | ﹤0.01% |
+2,300
| New | +$33.9K |
|
6865
CALL
Assured Guaranty
AGO
$3.73B
| $33K | ﹤0.01% |
400
+100
| +33% | +$8.31K |
|
6866
PUT
Alpha and Omega Semiconductor
AOSL
$829M
| $33K | ﹤0.01% |
1,200
+1,000
| +500% | +$27.8K |
|
6867
CALL
Appian
APPN
$2.11B
| $33K | ﹤0.01% |
1,100
-2,500
| -69% | -$75.1K |
|
6868
CALL
Algonquin Power & Utilities
AQN
$4.59B
| $33K | ﹤0.01% |
6,300
-800
| -11% | -$4.6K |
|
6869
Xtrackers Harvest CSI 500 China A-Shares Small Cap ETF
ASHS
$32.4M
| $33K | ﹤0.01% |
+892
| New | +$29.7K |
|
6870
CALL
Concrete Pumping Holdings
BBCP
$491M
| $33K | ﹤0.01% |
+4,700
| New | +$32.7K |
|
|
BHR
6871
PUT
Braemar Hotels & Resorts
BHR
$163M
| $33K | ﹤0.01% |
12,200
-200
| -2% | -$506 |
|
|
CMRC
6872
Commerce.com Inc Series 1
CMRC
$272M
| $33K | ﹤0.01% |
+6,617
| New | +$31.8K |
|
6873
VanEck ChiNext Innovators ETF
CNXT
$104M
| $33K | ﹤0.01% |
+753
| New | +$26.4K |
|
6874
CALL
DNOW Inc
DNOW
$2.44B
| $33K | ﹤0.01% |
2,200
-2,100
| -49% | -$31.7K |
|
6875
Evolus
EOLS
$397M
| $33K | ﹤0.01% |
5,389
-24,361
| -82% | -$190K |
|
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.