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 |
iShares Russell 2000 ETF
IWM
|
+$67.5M |
| 2 |
Palantir
PLTR
|
+$64.7M |
| 3 |
PARA
Paramount Global Class B
PARA
|
+$31.5M |
| 4 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$30.7M |
| 5 |
Carnival Corporation Ltd
CCL
|
+$25.7M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Amazon
AMZN
|
+$66M |
| 2 |
Tesla
TSLA
|
+$53.7M |
| 3 |
Alphabet (Google) Class C
GOOG
|
+$38.1M |
| 4 |
Invesco QQQ Trust
QQQ
|
+$37.6M |
| 5 |
AutoZone
AZO
|
+$28.5M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.65% |
| 2 | Consumer Discretionary | 0.49% |
| 3 | Healthcare | 0.32% |
| 4 | Financials | 0.3% |
| 5 | Industrials | 0.29% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
|
SRC
4451
PUT
DELISTED
SPIRIT REALTY CAPITAL, INC.
SRC
| $242K | ﹤0.01% |
57
+13
| +30% | +$532 |
|
|
TLMD
4452
CALL
DELISTED
SOC Telemed, Inc. Class A Common Stock
TLMD
| $242K | ﹤0.01% |
385
+365
| +1,825% | +$2.74K |
|
4453
CALL
Adaptive Biotechnologies
ADPT
$3.61B
| $241K | ﹤0.01% |
60
-138
| -70% | -$7.47K |
|
4454
PUT
Apogee Enterprises
APOG
$833M
| $241K | ﹤0.01% |
59
-50
| -46% | -$1.89K |
|
4455
CRISPR Therapeutics
CRSP
$4.69B
| $241K | ﹤0.01% |
1,980
-11,953
| -86% | -$1.8M |
|
4456
CALL
Warrior Met Coal
HCC
$4.17B
| $241K | ﹤0.01% |
141
-7
| -5% | -$148 |
|
4457
PUT
Sabra Healthcare REIT
SBRA
$5.56B
| $241K | ﹤0.01% |
139
-11
| -7% | -$193 |
|
4458
Stem
STEM
$44.3M
| $241K | ﹤0.01% |
+455
| New | +$292K |
|
4459
PUT
Evolus
EOLS
$397M
| $240K | ﹤0.01% |
+185
| New | +$1.71K |
|
4460
CALL
Ethan Allen Interiors
ETD
$600M
| $240K | ﹤0.01% |
87
-61
| -41% | -$1.53K |
|
4461
Itron
ITRI
$4.48B
| $240K | ﹤0.01% |
+2,713
| New | +$268K |
|
4462
PUT
Leslie's
LESL
$8.33M
| $240K | ﹤0.01% |
+5
| New | +$2.55K |
|
4463
CALL
Manchester United
MANU
$4.03B
| $240K | ﹤0.01% |
153
+105
| +219% | +$1.77K |
|
|
MGIC
4464
CALL
DELISTED
Magic Software Enterprises
MGIC
| $240K | ﹤0.01% |
158
+147
| +1,336% | +$2.42K |
|
4465
PUT
Mercury Systems
MRCY
$5.41B
| $240K | ﹤0.01% |
34
-16
| -32% | -$1.16K |
|
4466
ScottsMiracle-Gro
SMG
$4.09B
| $240K | ﹤0.01% |
982
-2,127
| -68% | -$482K |
|
4467
WillScot Mobile Mini Holdings
WSC
$4.37B
| $240K | ﹤0.01% |
+8,649
| New | +$227K |
|
4468
Clarivate
CLVT
$1.38B
| $239K | ﹤0.01% |
+9,060
| New | +$248K |
|
|
DESP
4469
CALL
DELISTED
Despegar.com
DESP
| $239K | ﹤0.01% |
176
+123
| +232% | +$1.57K |
|
4470
Eversource Energy
ES
$28.1B
| $239K | ﹤0.01% |
2,770
-225
| -8% | -$19.1K |
|
4471
PUT
Idacorp
IDA
$8B
| $239K | ﹤0.01% |
+24
| New | +$2.19K |
|
4472
CALL
Nice
NICE
$6.15B
| $239K | ﹤0.01% |
11
-10
| -48% | -$2.5K |
|
4473
QuantumScape Corp
QS
$3.05B
| $239K | ﹤0.01% |
5,350
-15,359
| -74% | -$805K |
|
4474
PUT
uniQure
QURE
$2.78B
| $239K | ﹤0.01% |
71
-190
| -73% | -$6.81K |
|
|
THR
4475
CALL
DELISTED
Thermon Group Holdings
THR
| $239K | ﹤0.01% |
+123
| New | +$2.24K |
|
Similar funds
Simplex Trading's Q1 2021 Portfolio in Review
As of Q1 2021, Simplex Trading held 10,706 positions worth $55.7B, down 28% from $77.2B the previous quarter. Its ten largest holdings account for 43% of the portfolio.
Simplex Trading withdrew a net $23.5B in Q1 2021, closing 1,706 positions and reducing 3,151 holdings. Its most notable exit was Alphabet (Google) Class C, an estimated $38.1M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.65% of assets, up from 0.37% a quarter earlier, followed by Consumer Discretionary and Healthcare.
Against the trend, Simplex Trading opened a new position in Pfizer worth $16.8M.
- Simplex Trading's largest Q1 2021 buy was Pfizer: 464,628 shares worth $16.8M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q1 2021, an estimated $67.5M increase.
- Simplex Trading's biggest Q1 2021 reduction was Amazon, cutting an estimated $66M.
- Simplex Trading fully exited Alphabet (Google) Class C in Q1 2021, selling an estimated $38.1M.
- Simplex Trading's ten largest holdings make up 43% of its $55.7B portfolio in Q1 2021.
- Simplex Trading opened 2,258 new positions and closed 1,706 in Q1 2021.
- Simplex Trading's portfolio value fell 28% quarter-over-quarter to $55.7B.
Based on Simplex Trading's 13F filing for Q1 2021, filed 26 Apr 2021.