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 | |
|---|---|---|---|---|---|---|
4651
CALL
Spectrum Brands
SPB
$2.04B
| $212K | ﹤0.01% |
25
| – | – |
|
4652
CALL
XPEL
XPEL
$1.22B
| $212K | ﹤0.01% |
41
-7
| -15% | -$377 |
|
|
AMBR
4653
Amber International Holding Ltd
AMBR
$134M
| $212K | ﹤0.01% |
1,809
+1,709
| +1,709% | +$236K |
|
|
EVA
4654
CALL
DELISTED
Enviva Inc.
EVA
| $212K | ﹤0.01% |
44
-34
| -44% | -$1.68K |
|
4655
PUT
Alector
ALEC
$180M
| $211K | ﹤0.01% |
105
-38
| -27% | -$681 |
|
4656
PUT
Black Stone Minerals
BSM
$3.14B
| $211K | ﹤0.01% |
243
+174
| +252% | +$1.54K |
|
4657
International Seaways
INSW
$4.71B
| $211K | ﹤0.01% |
+10,936
| New | +$203K |
|
4658
IonQ
IONQ
$13.4B
| $211K | ﹤0.01% |
+19,629
| New | +$228K |
|
4659
CALL
VICI Properties
VICI
$29B
| $211K | ﹤0.01% |
75
+61
| +436% | +$1.66K |
|
|
SEAH
4660
PUT
DELISTED
Sports Entertainment Acquisition Corp.
SEAH
| $211K | ﹤0.01% |
+216
| New | +$2.21K |
|
4661
PUT
Floor & Decor
FND
$5.98B
| $210K | ﹤0.01% |
22
-43
| -66% | -$4.19K |
|
4662
CALL
Green Dot
GDOT
$743M
| $210K | ﹤0.01% |
46
-191
| -81% | -$9.95K |
|
4663
Hudbay
HBM
$10.1B
| $210K | ﹤0.01% |
30,631
+30,601
| +102,003% | +$210K |
|
4664
Leidos
LDOS
$14.1B
| $210K | ﹤0.01% |
+2,188
| New | +$221K |
|
|
PLYA
4665
CALL
DELISTED
Playa Hotels & Resorts
PLYA
| $210K | ﹤0.01% |
289
+285
| +7,125% | +$1.88K |
|
|
DOOR
4666
DELISTED
MASONITE INTERNATIONAL CORP
DOOR
| $210K | ﹤0.01% |
+1,830
| New | +$199K |
|
|
PCSB
4667
CALL
DELISTED
PCSB Financial Corporation
PCSB
| $210K | ﹤0.01% |
+127
| New | +$2.08K |
|
|
CVA
4668
DELISTED
Covanta Holding Corporation
CVA
| $210K | ﹤0.01% |
+15,198
| New | +$217K |
|
|
ACB
4669
Aurora Cannabis
ACB
$175M
| $209K | ﹤0.01% |
2,251
+51
| +2% | +$5.7K |
|
|
SLAI
4670
CALL
DELISTED
SOLAI Ltd ADS
SLAI
| $209K | ﹤0.01% |
1
-2
| -67% | -$2.53K |
|
|
ONT
4671
Onterris Inc
ONT
$731M
| $209K | ﹤0.01% |
4,184
+2,777
| +197% | +$117K |
|
4672
Progyny
PGNY
$2.47B
| $209K | ﹤0.01% |
4,713
-2,668
| -36% | -$125K |
|
4673
CALL
TFS Financial
TFSL
$5.06B
| $209K | ﹤0.01% |
103
-126
| -55% | -$2.46K |
|
4674
Workiva
WK
$3.29B
| $209K | ﹤0.01% |
2,371
-9,596
| -80% | -$950K |
|
|
TECX
4675
CALL
Tectonic Therapeutic
TECX
$538M
| $209K | ﹤0.01% |
14
+11
| +367% | +$1.79K |
|
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.