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 | |
|---|---|---|---|---|---|---|
826
iShares MSCI Australia ETF
EWA
$1.34B
| $4.97M | 0.01% |
200,510
+31,336
| +19% | +$779K |
|
827
MGM Resorts International
MGM
$11.7B
| $4.97M | 0.01% |
130,813
+130,505
| +42,372% | +$4.55M |
|
828
CALL
Sonos
SONO
$1.75B
| $4.97M | 0.01% |
1,326
-265
| -17% | -$8.94K |
|
829
CALL
Nutanix
NTNX
$14.9B
| $4.96M | 0.01% |
1,868
-515
| -22% | -$15.7K |
|
830
CALL
Royal Gold
RGLD
$17.1B
| $4.96M | 0.01% |
461
-43
| -9% | -$4.59K |
|
|
NVTA
831
CALL
DELISTED
Invitae Corporation
NVTA
| $4.95M | 0.01% |
1,295
-701
| -35% | -$31.9K |
|
832
PUT
MarketAxess Holdings
MKTX
$4.15B
| $4.93M | 0.01% |
99
+30
| +43% | +$16K |
|
833
CALL
Parker-Hannifin
PH
$125B
| $4.92M | 0.01% |
156
+30
| +24% | +$8.66K |
|
834
CALL
Huntington Ingalls Industries
HII
$11.3B
| $4.92M | 0.01% |
239
+130
| +119% | +$23.3K |
|
835
CALL
The Greenbrier Companies
GBX
$1.61B
| $4.92M | 0.01% |
1,041
+965
| +1,270% | +$41.2K |
|
|
AYX
836
PUT
DELISTED
Alteryx Inc
AYX
| $4.91M | 0.01% |
592
+105
| +22% | +$11.1K |
|
837
CALL
Aflac
AFL
$63.9B
| $4.9M | 0.01% |
957
+171
| +22% | +$8.21K |
|
838
PUT
Apollo Global Management
APO
$70.7B
| $4.89M | 0.01% |
1,041
+736
| +241% | +$35.8K |
|
839
PUT
PagSeguro Digital
PAGS
$2.57B
| $4.89M | 0.01% |
1,056
+199
| +23% | +$10.7K |
|
|
RDS.A
840
DELISTED
Royal Dutch Shell PLC ADS Class A
RDS.A
| $4.88M | 0.01% |
+124,530
| New | +$5.01M |
|
|
TIGR
841
PUT
UP Fintech Holding
TIGR
$845M
| $4.88M | 0.01% |
2,743
+1,862
| +211% | +$37.9K |
|
842
CALL
Dominion Energy
D
$62.5B
| $4.88M | 0.01% |
642
-220
| -26% | -$16K |
|
843
CALL
Dick's Sporting Goods
DKS
$18.4B
| $4.85M | 0.01% |
637
-313
| -33% | -$22.5K |
|
844
CALL
Restaurant Brands International
QSR
$25.1B
| $4.83M | 0.01% |
743
-222
| -23% | -$13.8K |
|
845
PUT
FuelCell Energy
FCEL
$1.7B
| $4.82M | 0.01% |
112
+39
| +53% | +$20.9K |
|
846
CALL
Danaher
DHR
$135B
| $4.82M | 0.01% |
241
-51
| -17% | -$10.4K |
|
847
PUT
Stanley Black & Decker
SWK
$14.2B
| $4.81M | 0.01% |
241
-185
| -43% | -$33.5K |
|
848
CALL
Vanguard Consumer Discretionary ETF
VCR
$5.84B
| $4.81M | 0.01% |
278
+62
| +29% | +$18K |
|
849
PUT
Ziff Davis
ZD
$1.9B
| $4.81M | 0.01% |
461
+240
| +109% | +$22.6K |
|
850
CALL
Boston Scientific
BSX
$65.8B
| $4.8M | 0.01% |
1,242
-892
| -42% | -$33.8K |
|
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.