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 | |
|---|---|---|---|---|---|---|
1701
CALL
Transmedics
TMDX
$2.5B
| $3.87M | ﹤0.01% |
34,500
+400
| +1% | +$46.8K |
|
1702
CALL
Floor & Decor
FND
$5.81B
| $3.86M | ﹤0.01% |
52,400
+6,100
| +13% | +$500K |
|
|
JMIA
1703
PUT
Jumia Technologies
JMIA
$726M
| $3.86M | ﹤0.01% |
332,500
+250,500
| +305% | +$1.83M |
|
1704
PUT
Old Dominion Freight Line
ODFL
$48.5B
| $3.86M | ﹤0.01% |
27,400
+5,700
| +26% | +$873K |
|
1705
CALL
Fastenal
FAST
$54B
| $3.84M | ﹤0.01% |
78,400
-9,500
| -11% | -$449K |
|
1706
CALL
Motorola Solutions
MSI
$69.4B
| $3.84M | ﹤0.01% |
8,400
-3,300
| -28% | -$1.49M |
|
1707
CALL
Boyd Gaming
BYD
$6.47B
| $3.84M | ﹤0.01% |
44,400
-1,300
| -3% | -$109K |
|
1708
CALL
Exelixis
EXEL
$13.9B
| $3.84M | ﹤0.01% |
92,900
-19,700
| -17% | -$792K |
|
|
1709
PUT
Fastenal
FAST
$54B
| $3.83M | ﹤0.01% |
78,200
-1,100
| -1% | -$52K |
|
1710
Arm
ARM
$278B
| $3.83M | ﹤0.01% |
+27,036
| New | +$3.94M |
|
|
SERV
1711
PUT
Serve Robotics
SERV
$409M
| $3.83M | ﹤0.01% |
328,900
+119,000
| +57% | +$1.3M |
|
|
GRAL
1712
CALL
GRAIL Inc
GRAL
$2.91B
| $3.83M | ﹤0.01% |
64,700
-800
| -1% | -$30.6K |
|
1713
CALL
Capri Holdings
CPRI
$1.77B
| $3.82M | ﹤0.01% |
192,000
+8,700
| +5% | +$174K |
|
1714
Hilton Worldwide
HLT
$74B
| $3.82M | ﹤0.01% |
14,729
-2,821
| -16% | -$763K |
|
1715
CALL
Monster Beverage
MNST
$91.4B
| $3.82M | ﹤0.01% |
56,700
-23,200
| -29% | -$1.45M |
|
1716
Advance Auto Parts
AAP
$3.37B
| $3.8M | ﹤0.01% |
61,942
-62,820
| -50% | -$3.71M |
|
1717
PUT
Strive Inc
ASST
$961M
| $3.8M | ﹤0.01% |
76,030
+73,265
| +2,650% | +$6.96M |
|
1718
PUT
Ouster
OUST
$2.29B
| $3.79M | ﹤0.01% |
140,200
+85,400
| +156% | +$2.38M |
|
|
WRD
1719
PUT
WeRide Inc
WRD
$1.75B
| $3.79M | ﹤0.01% |
382,900
+118,800
| +45% | +$1.13M |
|
1720
PUT
Cencora
COR
$60.3B
| $3.78M | ﹤0.01% |
12,100
+2,600
| +27% | +$765K |
|
1721
PUT
Liquidia Corp
LQDA
$7.67B
| $3.78M | ﹤0.01% |
166,100
-37,800
| -19% | -$820K |
|
1722
Direxion Daily CSI China Internet Index Bull 2X ETF
CWEB
$218M
| $3.77M | ﹤0.01% |
+65,534
| New | +$3.06M |
|
1723
CALL
Nasdaq
NDAQ
$51.5B
| $3.77M | ﹤0.01% |
42,600
+15,200
| +55% | +$1.41M |
|
|
ETNB
1724
PUT
DELISTED
89bio
ETNB
| $3.77M | ﹤0.01% |
256,200
+230,400
| +893% | +$2.35M |
|
1725
PUT
OneMain Financial
OMF
$6.9B
| $3.77M | ﹤0.01% |
66,700
+3,000
| +5% | +$177K |
|
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.