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 | |
|---|---|---|---|---|---|---|
5176
Nomad Foods
NOMD
$1.66B
| $164K | ﹤0.01% |
12,541
+12,272
| +4,562% | +$192K |
|
|
PPIH
5177
Perma-Pipe International
PPIH
$196M
| $164K | ﹤0.01% |
+7,020
| New | +$181K |
|
5178
PUT
PubMatic
PUBM
$585M
| $164K | ﹤0.01% |
19,900
-32,900
| -62% | -$335K |
|
5179
PUT
Sky Harbour Group
SKYH
$369M
| $164K | ﹤0.01% |
16,700
+6,400
| +62% | +$65.3K |
|
5180
CALL
Synaptics
SYNA
$4.19B
| $164K | ﹤0.01% |
2,400
-5,300
| -69% | -$360K |
|
5181
Adtran
ADTN
$689M
| $163K | ﹤0.01% |
17,440
+14,731
| +544% | +$137K |
|
5182
CALL
Crexendo
CXDO
$223M
| $163K | ﹤0.01% |
25,200
+10,600
| +73% | +$65.7K |
|
5183
PUT
Shoals Technologies Group
SHLS
$1.47B
| $163K | ﹤0.01% |
22,000
-2,400
| -10% | -$14.8K |
|
5184
Tyson Foods
TSN
$20.4B
| $163K | ﹤0.01% |
3,013
-15,019
| -83% | -$829K |
|
5185
PUT
USA Compression Partners
USAC
$3.79B
| $163K | ﹤0.01% |
6,800
-600
| -8% | -$14.4K |
|
|
EMPD
5186
PUT
Empery Digital
EMPD
$79.8M
| $163K | ﹤0.01% |
+21,800
| New | +$197K |
|
|
MASI
5187
CALL
DELISTED
Masimo
MASI
| $162K | ﹤0.01% |
1,100
-300
| -21% | -$45.4K |
|
5188
PUT
Unisys
UIS
$209M
| $162K | ﹤0.01% |
41,600
+10,100
| +32% | +$41K |
|
|
DYNC
5189
PUT
Dynamix Corp
DYNC
$240M
| $162K | ﹤0.01% |
+15,600
| New | +$168K |
|
|
MTSR
5190
CALL
DELISTED
Metsera Inc
MTSR
| $162K | ﹤0.01% |
3,100
+600
| +24% | +$22.1K |
|
|
AKRO
5191
PUT
DELISTED
Akero Therapeutics
AKRO
| $161K | ﹤0.01% |
3,400
-19,400
| -85% | -$939K |
|
5192
Clearwater Paper
CLW
$339M
| $161K | ﹤0.01% |
7,769
+7,359
| +1,795% | +$178K |
|
|
BRSL
5193
Brightstar Lottery PLC
BRSL
$1.84B
| $161K | ﹤0.01% |
9,378
-24,826
| -73% | -$397K |
|
5194
CALL
Northwest Natural Holdings
NWN
$2.06B
| $161K | ﹤0.01% |
3,600
+2,400
| +200% | +$99.6K |
|
5195
Silicon Laboratories
SLAB
$7.17B
| $161K | ﹤0.01% |
+1,231
| New | +$168K |
|
|
GMEU
5196
PUT
T-REX 2X Long GME Daily Target ETF
GMEU
$20.9M
| $161K | ﹤0.01% |
6,500
+5,500
| +550% | +$79.2K |
|
5197
CALL
Brookfield Infrastructure
BIPC
$5.2B
| $160K | ﹤0.01% |
3,900
-1,700
| -30% | -$68.9K |
|
5198
PUT
Badger Meter
BMI
$3.89B
| $160K | ﹤0.01% |
+900
| New | +$177K |
|
5199
CALL
Essex Property Trust
ESS
$18.3B
| $160K | ﹤0.01% |
600
| – | – |
|
|
GTLS
5200
PUT
DELISTED
Chart Industries
GTLS
| $160K | ﹤0.01% |
800
-500
| -38% | -$95K |
|
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.