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 | |
|---|---|---|---|---|---|---|
3876
PUT
Xponential Fitness
XPOF
$282M
| $356K | ﹤0.01% |
47,600
-1,600
| -3% | -$13.3K |
|
|
LAZR
3877
PUT
DELISTED
Luminar Technologies
LAZR
| $355K | ﹤0.01% |
123,900
-49,700
| -29% | -$189K |
|
3878
Rockwell Automation
ROK
$52.4B
| $355K | ﹤0.01% |
+1,071
| New | +$305K |
|
3879
CALL
Smith & Wesson
SWBI
$657M
| $355K | ﹤0.01% |
41,000
-15,200
| -27% | -$144K |
|
3880
Palladyne AI
PDYN
$239M
| $355K | ﹤0.01% |
41,066
+24,515
| +148% | +$174K |
|
3881
PUT
Aehr Test Systems
AEHR
$2.27B
| $354K | ﹤0.01% |
27,400
-3,100
| -10% | -$29.5K |
|
3882
PUT
Check Point Software Technologies
CHKP
$14.1B
| $354K | ﹤0.01% |
1,600
+300
| +23% | +$66K |
|
3883
Doximity
DOCS
$3.85B
| $354K | ﹤0.01% |
+5,786
| New | +$323K |
|
|
KREF
3884
KKR Real Estate Finance Trust
KREF
$471M
| $354K | ﹤0.01% |
40,458
+25,682
| +174% | +$236K |
|
|
CMPS
3885
CALL
Compass Pathways
CMPS
$1.46B
| $352K | ﹤0.01% |
125,800
+64,400
| +105% | +$242K |
|
3886
PUT
QuinStreet
QNST
$916M
| $352K | ﹤0.01% |
21,900
+13,700
| +167% | +$220K |
|
3887
CALL
Rocket Pharmaceuticals
RCKT
$343M
| $352K | ﹤0.01% |
144,000
+58,600
| +69% | +$297K |
|
3888
CALL
Radian Group
RDN
$5.22B
| $352K | ﹤0.01% |
9,800
-400
| -4% | -$13.4K |
|
|
SUPV
3889
CALL
Grupo Supervielle
SUPV
$842M
| $352K | ﹤0.01% |
33,300
-13,800
| -29% | -$187K |
|
|
JNPR
3890
DELISTED
Juniper Networks
JNPR
| $351K | ﹤0.01% |
8,794
+7,893
| +876% | +$283K |
|
3891
CALL
Kingstone Companies
KINS
$292M
| $351K | ﹤0.01% |
22,800
+5,800
| +34% | +$96.2K |
|
3892
CALL
STAG Industrial
STAG
$7.79B
| $351K | ﹤0.01% |
9,700
-11,600
| -54% | -$401K |
|
3893
PUT
Avery Dennison
AVY
$12.9B
| $350K | ﹤0.01% |
2,000
+1,900
| +1,900% | +$333K |
|
3894
CALL
Comstock
LODE
$215M
| $350K | ﹤0.01% |
92,500
-79,000
| -46% | -$220K |
|
3895
CALL
Tucows
TCX
$101M
| $350K | ﹤0.01% |
17,800
+17,600
| +8,800% | +$315K |
|
3896
Appian
APPN
$2.01B
| $349K | ﹤0.01% |
11,708
-11,944
| -50% | -$359K |
|
|
3897
PUT
Appian
APPN
$2.01B
| $349K | ﹤0.01% |
11,700
-34,600
| -75% | -$1.04M |
|
3898
CALL
Humacyte
HUMA
$170M
| $349K | ﹤0.01% |
167,200
-60,000
| -26% | -$115K |
|
3899
CALL
Ryder
R
$9.98B
| $349K | ﹤0.01% |
2,200
+1,300
| +144% | +$191K |
|
3900
Companhia Siderúrgica Nacional
SID
$1.46B
| $349K | ﹤0.01% |
249,365
-49,306
| -17% | -$76.2K |
|
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.