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 | |
|---|---|---|---|---|---|---|
7051
AMERISAFE
AMSF
$569M
| $27K | ﹤0.01% |
+621
| New | +$27.8K |
|
7052
Anixa Biosciences
ANIX
$117M
| $27K | ﹤0.01% |
+8,184
| New | +$25.9K |
|
7053
CALL
Alpha and Omega Semiconductor
AOSL
$830M
| $27K | ﹤0.01% |
1,000
-3,900
| -80% | -$108K |
|
7054
PUT
AppFolio
APPF
$6.71B
| $27K | ﹤0.01% |
+100
| New | +$27K |
|
7055
PUT
Arena Group
AREN
$53.3M
| $27K | ﹤0.01% |
5,000
-8,600
| -63% | -$53.5K |
|
7056
PUT
United States Brent Oil Fund
BNO
$776M
| $27K | ﹤0.01% |
900
-400
| -31% | -$12.1K |
|
7057
CALL
Perspective Therapeutics
CATX
$318M
| $27K | ﹤0.01% |
7,900
+4,300
| +119% | +$15.7K |
|
|
CHCT
7058
CALL
Community Healthcare Trust
CHCT
$541M
| $27K | ﹤0.01% |
1,800
+300
| +20% | +$4.7K |
|
7059
CALL
Clearfield
CLFD
$396M
| $27K | ﹤0.01% |
800
-400
| -33% | -$14.9K |
|
7060
PUT
Contango Silver & Gold Inc
CTGO
$519M
| $27K | ﹤0.01% |
+1,100
| New | +$23.4K |
|
|
CWBC
7061
CALL
Community West Bancshares
CWBC
$694M
| $27K | ﹤0.01% |
+1,300
| New | +$26.8K |
|
|
DAO
7062
Youdao
DAO
$1.92B
| $27K | ﹤0.01% |
+2,758
| New | +$24.6K |
|
|
DVAX
7063
PUT
DELISTED
Dynavax Technologies
DVAX
| $27K | ﹤0.01% |
2,800
-3,500
| -56% | -$36.4K |
|
7064
PUT
Vaalco Energy
EGY
$554M
| $27K | ﹤0.01% |
6,900
+1,000
| +17% | +$3.86K |
|
7065
PUT
Evolus
EOLS
$392M
| $27K | ﹤0.01% |
4,500
-7,000
| -61% | -$54.6K |
|
7066
Vertical Aerospace
EVTL
$157M
| $27K | ﹤0.01% |
5,260
+4,377
| +496% | +$24.3K |
|
7067
PUT
MicroSectors FANG+ ETNs due Jan 8 2038
FNGS
$538M
| $27K | ﹤0.01% |
400
+300
| +300% | +$20K |
|
|
IMMP
7068
CALL
Immutep
IMMP
$56.1M
| $27K | ﹤0.01% |
15,900
-2,900
| -15% | -$4.92K |
|
7069
Ironwood Pharmaceuticals
IRWD
$596M
| $27K | ﹤0.01% |
20,739
+19,963
| +2,573% | +$20.7K |
|
7070
CALL
Ispire Technology
ISPR
$87.2M
| $27K | ﹤0.01% |
10,700
+10,300
| +2,575% | +$29.9K |
|
7071
J&J Snack Foods
JJSF
$1.52B
| $27K | ﹤0.01% |
284
+197
| +226% | +$21.8K |
|
7072
CALL
Korn Ferry
KFY
$4.32B
| $27K | ﹤0.01% |
400
-400
| -50% | -$29.2K |
|
7073
Koppers
KOP
$944M
| $27K | ﹤0.01% |
989
+908
| +1,121% | +$28K |
|
7074
LENSAR
LNSR
$63.9M
| $27K | ﹤0.01% |
+2,192
| New | +$27.8K |
|
7075
Marcus Corp
MCS
$764M
| $27K | ﹤0.01% |
+1,765
| New | +$28.3K |
|
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.