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 | |
|---|---|---|---|---|---|---|
5151
Mineralys Therapeutics
MLYS
$2.23B
| $167K | ﹤0.01% |
+4,423
| New | +$95.7K |
|
5152
CALL
RELX
RELX
$61.9B
| $167K | ﹤0.01% |
3,500
-1,800
| -34% | -$89K |
|
5153
Atomera
ATOM
$197M
| $166K | ﹤0.01% |
37,712
+11,771
| +45% | +$48.3K |
|
5154
AB InBev
BUD
$167B
| $166K | ﹤0.01% |
+2,799
| New | +$176K |
|
5155
PUT
Crinetics Pharmaceuticals
CRNX
$8.87B
| $166K | ﹤0.01% |
4,000
+3,800
| +1,900% | +$122K |
|
5156
PUT
Globant
GLOB
$1.56B
| $166K | ﹤0.01% |
2,900
+1,000
| +53% | +$73.6K |
|
|
NLOP
5157
CALL
Net Lease Office Properties
NLOP
$175M
| $166K | ﹤0.01% |
5,600
-28,400
| -84% | -$891K |
|
5158
PUT
TPG
TPG
$6.87B
| $166K | ﹤0.01% |
2,900
-69,900
| -96% | -$4.13M |
|
5159
CALL
Tronox
TROX
$943M
| $166K | ﹤0.01% |
41,400
+39,400
| +1,970% | +$180K |
|
5160
CALL
WesBanco
WSBC
$3.97B
| $166K | ﹤0.01% |
+5,200
| New | +$166K |
|
|
AIRJ
5161
Montana Technologies Corp
AIRJ
$303M
| $166K | ﹤0.01% |
+35,412
| New | +$166K |
|
5162
PUT
Acadia Healthcare
ACHC
$2.72B
| $165K | ﹤0.01% |
6,700
+4,900
| +272% | +$109K |
|
5163
Atlanta Braves Holdings Series A
BATRA
$3.47B
| $165K | ﹤0.01% |
3,633
+3,370
| +1,281% | +$159K |
|
|
STEX
5164
PUT
Streamex Corp
STEX
$71.7M
| $165K | ﹤0.01% |
+28,700
| New | +$156K |
|
5165
Cheesecake Factory
CAKE
$5.07B
| $165K | ﹤0.01% |
+3,020
| New | +$185K |
|
5166
CALL
Driven Brands
DRVN
$2.33B
| $165K | ﹤0.01% |
10,300
+9,700
| +1,617% | +$169K |
|
5167
Harmony Biosciences
HRMY
$2.02B
| $165K | ﹤0.01% |
+6,003
| New | +$207K |
|
5168
CALL
KB Financial Group
KB
$41.5B
| $165K | ﹤0.01% |
2,000
-8,300
| -81% | -$681K |
|
5169
PUT
Manulife Financial
MFC
$74.4B
| $165K | ﹤0.01% |
5,300
+900
| +20% | +$27.8K |
|
5170
PUT
Bar Harbor Bankshares
BHB
$663M
| $164K | ﹤0.01% |
5,400
+5,300
| +5,300% | +$166K |
|
5171
Dakota Gold
DC
$601M
| $164K | ﹤0.01% |
+36,070
| New | +$152K |
|
5172
PUT
Ecolab
ECL
$77.8B
| $164K | ﹤0.01% |
600
-1,800
| -75% | -$489K |
|
5173
Fossil Group
FOSL
$286M
| $164K | ﹤0.01% |
63,884
+59,014
| +1,212% | +$139K |
|
5174
Lightspeed Commerce
LSPD
$1.28B
| $164K | ﹤0.01% |
14,267
-34,106
| -71% | -$417K |
|
|
LITS
5175
PUT
Lite Strategy Inc
LITS
$32.8M
| $164K | ﹤0.01% |
+68,000
| New | +$280K |
|
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.