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 | |
|---|---|---|---|---|---|---|
3126
iShares MSCI Chile ETF
ECH
$999M
| $593K | ﹤0.01% |
+17,318
| New | +$562K |
|
3127
CALL
Lakeland Industries
LAKE
$108M
| $593K | ﹤0.01% |
213
-107
| -33% | -$3.32K |
|
3128
CALL
US Physical Therapy
USPH
$1.21B
| $593K | ﹤0.01% |
57
-46
| -45% | -$5.72K |
|
3129
PUT
Tredegar Corp
TG
$265M
| $592K | ﹤0.01% |
395
-122
| -24% | -$1.95K |
|
|
ATHX
3130
DELISTED
Athersys, Inc. Common Stock
ATHX
| $591K | ﹤0.01% |
13,153
+11,280
| +602% | +$586K |
|
3131
PUT
Popular Inc
BPOP
$11B
| $590K | ﹤0.01% |
84
-118
| -58% | -$7.64K |
|
3132
CALL
Dover
DOV
$27.6B
| $589K | ﹤0.01% |
43
-96
| -69% | -$12.2K |
|
3133
Hyster-Yale Materials Handling
HY
$612M
| $589K | ﹤0.01% |
+6,762
| New | +$592K |
|
3134
PUT
Insmed
INSM
$22.6B
| $589K | ﹤0.01% |
173
+161
| +1,342% | +$6.15K |
|
3135
PUT
ProQR Therapeutics
PRQR
$241M
| $589K | ﹤0.01% |
+892
| New | +$4.56K |
|
3136
PUT
Terex
TEX
$7.78B
| $589K | ﹤0.01% |
128
+37
| +41% | +$1.52K |
|
|
GTHX
3137
CALL
DELISTED
G1 Therapeutics, Inc. Common Stock
GTHX
| $589K | ﹤0.01% |
245
+129
| +111% | +$3K |
|
|
CUB
3138
CALL
DELISTED
Cubic Corporation
CUB
| $589K | ﹤0.01% |
79
+50
| +172% | +$3.41K |
|
3139
Ichor Holdings
ICHR
$2.35B
| $588K | ﹤0.01% |
10,933
+8,993
| +464% | +$383K |
|
3140
CALL
Sinclair Inc
SBGI
$997M
| $588K | ﹤0.01% |
201
-366
| -65% | -$12.2K |
|
3141
PUT
Warner Music
WMG
$14.9B
| $587K | ﹤0.01% |
171
+48
| +39% | +$1.72K |
|
|
NAGE
3142
CALL
Niagen Bioscience
NAGE
$259M
| $587K | ﹤0.01% |
629
+533
| +555% | +$4.22K |
|
|
RIDE
3143
DELISTED
Lordstown Motors Corp. Class A Common Stock
RIDE
| $587K | ﹤0.01% |
3,330
-215
| -6% | -$67.6K |
|
3144
PUT
Pool Corp
POOL
$6.91B
| $586K | ﹤0.01% |
17
-16
| -48% | -$5.57K |
|
|
MGI
3145
PUT
DELISTED
MoneyGram International, Inc. New
MGI
| $586K | ﹤0.01% |
893
+790
| +767% | +$5.78K |
|
|
ADN
3146
CALL
DELISTED
Advent Technologies
ADN
| $585K | ﹤0.01% |
+15
| New | +$6.79K |
|
3147
PUT
Frontline
FRO
$8.74B
| $585K | ﹤0.01% |
819
+346
| +73% | +$2.38K |
|
3148
Nutrien
NTR
$33.2B
| $583K | ﹤0.01% |
10,820
+2,678
| +33% | +$146K |
|
3149
Purple Innovation
PRPL
$34.8M
| $583K | ﹤0.01% |
738
+469
| +174% | +$407K |
|
3150
Playtika
PLTK
$1.51B
| $582K | ﹤0.01% |
+21,399
| New | +$629K |
|
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.