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 | |
|---|---|---|---|---|---|---|
4601
Iridium Communications
IRDM
$4.7B
| $270K | ﹤0.01% |
+15,516
| New | +$383K |
|
4602
PUT
Morgan Stanley Direct Lending Fund
MSDL
$1.25B
| $270K | ﹤0.01% |
16,800
-22,400
| -57% | -$409K |
|
4603
Open Text
OTEX
$6.28B
| $270K | ﹤0.01% |
+7,242
| New | +$232K |
|
4604
CALL
Praxis Precision Medicines
PRAX
$8.11B
| $270K | ﹤0.01% |
5,100
+1,300
| +34% | +$63K |
|
4605
PUT
A2Z Smart Technologies
AZ
$241M
| $269K | ﹤0.01% |
33,700
+1,100
| +3% | +$10.4K |
|
4606
Denison Mines
DNN
$2.43B
| $269K | ﹤0.01% |
+97,984
| New | +$217K |
|
|
SJT
4607
CALL
San Juan Basin Royalty Trust
SJT
$119M
| $269K | ﹤0.01% |
44,600
-7,000
| -14% | -$41.2K |
|
4608
CALL
Vitesse Energy
VTS
$644M
| $269K | ﹤0.01% |
11,600
+2,200
| +23% | +$54.1K |
|
4609
CALL
Arq
ARQ
$83.3M
| $269K | ﹤0.01% |
37,700
+20,400
| +118% | +$135K |
|
4610
PUT
Genco Shipping & Trading
GNK
$1.1B
| $268K | ﹤0.01% |
15,100
+10,800
| +251% | +$179K |
|
4611
CALL
W.R. Berkley
WRB
$28.1B
| $268K | ﹤0.01% |
3,500
-1,500
| -30% | -$107K |
|
4612
PUT
Xperi
XPER
$364M
| $268K | ﹤0.01% |
41,400
-15,600
| -27% | -$103K |
|
4613
CALL
EverQuote
EVER
$949M
| $267K | ﹤0.01% |
11,700
+2,500
| +27% | +$60.4K |
|
4614
Howard Hughes
HHH
$3.94B
| $267K | ﹤0.01% |
3,256
-12,063
| -79% | -$893K |
|
4615
PUT
Precigen
PGEN
$1.94B
| $267K | ﹤0.01% |
81,200
-125,200
| -61% | -$353K |
|
|
ONIT
4616
CALL
Onity Group
ONIT
$342M
| $267K | ﹤0.01% |
+6,700
| New | +$269K |
|
4617
CALL
Hartford Financial Services
HIG
$39.9B
| $266K | ﹤0.01% |
2,000
+1,300
| +186% | +$167K |
|
4618
Cipher Digital
CIFR
$7.24B
| $265K | ﹤0.01% |
21,061
-139,117
| -87% | -$1.05M |
|
4619
iShares MSCI Mexico ETF
EWW
$1.89B
| $265K | ﹤0.01% |
+3,898
| New | +$243K |
|
|
PPLI
4620
PUT
People Inc
PPLI
$3.12B
| $265K | ﹤0.01% |
7,800
-300
| -4% | -$11.2K |
|
4621
CALL
Intapp
INTA
$2.44B
| $265K | ﹤0.01% |
6,500
+4,500
| +225% | +$195K |
|
4622
Absci
ABSI
$1.17B
| $264K | ﹤0.01% |
87,162
-57,361
| -40% | -$159K |
|
4623
JELD-WEN Holding
JELD
$110M
| $264K | ﹤0.01% |
53,817
+51,241
| +1,989% | +$274K |
|
4624
PUT
Fortress Biotech
FBIO
$111M
| $263K | ﹤0.01% |
+71,400
| New | +$181K |
|
4625
CALL
Hagerty
HGTY
$1.21B
| $263K | ﹤0.01% |
21,900
+19,300
| +742% | +$214K |
|
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.