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 Russell 2000 ETF
IWM
|
+$146M |
| 2 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$108M |
| 3 |
Apple
AAPL
|
+$62.9M |
| 4 |
Tesla
TSLA
|
+$51.9M |
| 5 |
Micron Technology
MU
|
+$39.5M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$108M |
| 2 |
Meta Platforms (Facebook)
META
|
+$104M |
| 3 |
Advanced Micro Devices
AMD
|
+$92.1M |
| 4 |
Amazon
AMZN
|
+$90.3M |
| 5 |
TSMC
TSM
|
+$82.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 98.28% |
| 2 | Technology | 0.76% |
| 3 | Consumer Discretionary | 0.21% |
| 4 | Communication Services | 0.19% |
| 5 | Healthcare | 0.15% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
5151
Worthington Enterprises
WOR
$3.06B
| $140K | ﹤0.01% |
2,608
-1,053
| -29% | -$58.7K |
|
5152
CALL
908 Devices
MASS
$415M
| $140K | ﹤0.01% |
+16,100
| New | +$124K |
|
5153
CALL
PDS Biotechnology
PDSB
$12.3M
| $140K | ﹤0.01% |
158,800
+158,500
| +52,833% | +$168K |
|
5154
PUT
AtriCure
ATRC
$2.62B
| $140K | ﹤0.01% |
5,000
| – | – |
|
|
KRMN
5155
PUT
Karman Holdings
KRMN
$5.3B
| $140K | ﹤0.01% |
2,800
+2,600
| +1,300% | +$168K |
|
5156
PUT
First Trust Exchange-Traded Fund VI Multi-Asset Diversified Income Index Fund
MDIV
$432M
| $140K | ﹤0.01% |
2,000
+1,900
| +1,900% | +$31.4K |
|
5157
iShares Copper and Metals Mining ETF
ICOP
$499M
| $140K | ﹤0.01% |
2,838
-4,736
| -63% | -$247K |
|
5158
CALL
iShares 25+ Year Treasury STRIPS Bond ETF
GOVZ
$328M
| $140K | ﹤0.01% |
+3,800
| New | +$137K |
|
|
APPX
5159
Tradr 2X Long APP Daily ETF
APPX
$86.8M
| $140K | ﹤0.01% |
3,452
+2,273
| +193% | +$86.6K |
|
|
BBNX
5160
CALL
Beta Bionics
BBNX
$874M
| $139K | ﹤0.01% |
8,900
+3,700
| +71% | +$44K |
|
5161
PUT
Teleflex
TFX
$5.86B
| $139K | ﹤0.01% |
1,100
| – | – |
|
5162
CALL
Verra Mobility
VRRM
$619M
| $139K | ﹤0.01% |
32,800
-18,400
| -36% | -$194K |
|
|
AVGG
5163
Leverage Shares 2X Long AVGO Daily ETF
AVGG
$44.3M
| $139K | ﹤0.01% |
5,093
+2,872
| +129% | +$94.2K |
|
5164
CALL
Skywest
SKYW
$3.85B
| $139K | ﹤0.01% |
1,400
-2,600
| -65% | -$231K |
|
|
QNT
5165
PUT
Quantinuum Inc
QNT
$1.83B
| $139K | ﹤0.01% |
+1,700
| New | +$109K |
|
5166
PUT
Altimmune
ALT
$665M
| $139K | ﹤0.01% |
45,700
-29,300
| -39% | -$87.5K |
|
|
XRN
5167
CALL
Chiron Real Estate Inc
XRN
$489M
| $139K | ﹤0.01% |
3,700
+3,000
| +429% | +$106K |
|
5168
Freshworks
FRSH
$3.32B
| $139K | ﹤0.01% |
13,709
+11,069
| +419% | +$98.6K |
|
5169
CALL
Harmony Biosciences
HRMY
$2.46B
| $138K | ﹤0.01% |
3,800
-14,400
| -79% | -$454K |
|
5170
Plexus
PLXS
$6.56B
| $138K | ﹤0.01% |
460
-18,227
| -98% | -$4.75M |
|
|
WCC
5171
CALL
WESCO International
WCC
$17.1B
| $138K | ﹤0.01% |
400
-2,000
| -83% | -$679K |
|
5172
CALL
Designer Brands
DBI
$267M
| $138K | ﹤0.01% |
23,700
+23,500
| +11,750% | +$165K |
|
5173
CALL
Kyverna Therapeutics
KYTX
$510M
| $138K | ﹤0.01% |
15,500
-12,300
| -44% | -$109K |
|
5174
CALL
Akebia Therapeutics
AKBA
$270M
| $138K | ﹤0.01% |
121,000
+39,900
| +49% | +$47.5K |
|
|
SEPN
5175
CALL
Septerna Inc
SEPN
$1.72B
| $137K | ﹤0.01% |
4,100
+1,700
| +71% | +$48.2K |
|
Similar funds
Simplex Trading's Q2 2026 Portfolio in Review
As of Q2 2026, Simplex Trading held 10,638 positions worth $171B, up 14% from $149B the previous quarter. Its ten largest holdings account for 50% of the portfolio.
Simplex Trading's Q2 2026 filing shows 1,714 new, 3,712 increased, 3,486 reduced and 1,487 closed positions. Its largest new stake was Micron Technology: 52,682 shares worth $60.8M. The largest sale was State Street SPDR S&P 500 ETF Trust, an estimated $108M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, down from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- Simplex Trading's largest Q2 2026 buy was Micron Technology: 52,682 shares worth $60.8M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q2 2026, an estimated $146M increase.
- Simplex Trading's biggest Q2 2026 reduction was State Street SPDR S&P 500 ETF Trust, cutting an estimated $108M.
- Simplex Trading fully exited Intel in Q2 2026, selling an estimated $76.6M.
- Simplex Trading's ten largest holdings make up 50% of its $171B portfolio in Q2 2026.
- Simplex Trading opened 1,714 new positions and closed 1,487 in Q2 2026.
- Simplex Trading's portfolio value rose 14% quarter-over-quarter to $171B.
Based on Simplex Trading's 13F filing for Q2 2026, filed 12 Aug 2026.