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 | |
|---|---|---|---|---|---|---|
7751
American Express Global Business Travel
GBTG
$4.93B
| $12K | ﹤0.01% |
1,524
+333
| +28% | +$2.47K |
|
7752
CALL
Helix Energy Solutions
HLX
$1.45B
| $12K | ﹤0.01% |
1,900
+1,200
| +171% | +$7.55K |
|
7753
Identive
INVE
$65.1M
| $12K | ﹤0.01% |
3,738
+2,204
| +144% | +$7.9K |
|
|
LADR
7754
Ladder Capital
LADR
$1.24B
| $12K | ﹤0.01% |
+1,133
| New | +$12.7K |
|
7755
Lesaka Technologies
LSAK
$392M
| $12K | ﹤0.01% |
3,062
+2,644
| +633% | +$11.9K |
|
7756
CALL
MGP Ingredients
MGPI
$379M
| $12K | ﹤0.01% |
500
-3,200
| -86% | -$92.8K |
|
7757
PUT
Miller Industries
MLR
$585M
| $12K | ﹤0.01% |
+300
| New | +$12.6K |
|
7758
PUT
Mueller Water Products
MWA
$3.93B
| $12K | ﹤0.01% |
500
-500
| -50% | -$12.8K |
|
7759
Nexa Resources
NEXA
$1.68B
| $12K | ﹤0.01% |
2,506
+2,105
| +525% | +$10.4K |
|
7760
NetSol Technologies
NTWK
$51.1M
| $12K | ﹤0.01% |
+2,654
| New | +$11.1K |
|
|
NVNO
7761
enVVeno Medical
NVNO
$7M
| $12K | ﹤0.01% |
+393
| New | +$40.1K |
|
7762
PUT
Organogenesis Holdings
ORGO
$329M
| $12K | ﹤0.01% |
3,000
-500
| -14% | -$2.32K |
|
7763
PUT
Oshkosh
OSK
$9.58B
| $12K | ﹤0.01% |
100
-2,400
| -96% | -$318K |
|
7764
One Stop Systems
OSS
$309M
| $12K | ﹤0.01% |
2,337
-11,221
| -83% | -$61.4K |
|
7765
PUT
Pacira BioSciences
PCRX
$1.04B
| $12K | ﹤0.01% |
500
+100
| +25% | +$2.46K |
|
7766
PDS Biotechnology
PDSB
$36.9M
| $12K | ﹤0.01% |
+12,405
| New | +$14.6K |
|
7767
CALL
Power Integrations
POWI
$3.37B
| $12K | ﹤0.01% |
300
-400
| -57% | -$19.3K |
|
7768
Prairie Operating Co
PROP
$71.9M
| $12K | ﹤0.01% |
+6,285
| New | +$17.9K |
|
|
PSTL
7769
PUT
Postal Realty Trust
PSTL
$724M
| $12K | ﹤0.01% |
+800
| New | +$12.1K |
|
|
HTT
7770
PUT
High Templar Tech Ltd
HTT
$382M
| $12K | ﹤0.01% |
2,900
-181,600
| -98% | -$728K |
|
7771
PUT
Resideo Technologies
REZI
$5.31B
| $12K | ﹤0.01% |
+300
| New | +$9.37K |
|
7772
PUT
Rackspace Technology
RXT
$972M
| $12K | ﹤0.01% |
8,600
+100
| +1% | +$134 |
|
|
SEM
7773
PUT
DELISTED
Select Medical
SEM
| $12K | ﹤0.01% |
+1,000
| New | +$13.3K |
|
7774
Snap-on
SNA
$20.9B
| $12K | ﹤0.01% |
+36
| New | +$11.8K |
|
7775
Teleflex
TFX
$5.92B
| $12K | ﹤0.01% |
100
-57
| -36% | -$6.91K |
|
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.