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 | |
|---|---|---|---|---|---|---|
8751
CALL
Aurinia Pharmaceuticals
AUPH
$1.97B
| – | – |
-688
| Closed | -$951K |
|
|
8752
Aurinia Pharmaceuticals
AUPH
$1.97B
| $0 | ﹤0.01% |
30,386
-18,839
| -38% | -$273K |
|
|
8753
PUT
Aurinia Pharmaceuticals
AUPH
$1.97B
| – | – |
-431
| Closed | -$596K |
|
8754
AeroVironment
AVAV
$7.57B
| – | – |
-3,010
| Closed | -$352K |
|
8755
CALL
Broadcom
AVGO
$1.82T
| – | – |
-8,070
| Closed | -$35.3M |
|
|
8756
Broadcom
AVGO
$1.82T
| $0 | ﹤0.01% |
103,370
-233,040
| -69% | -$10.8M |
|
|
8757
PUT
Broadcom
AVGO
$1.82T
| – | – |
-29,170
| Closed | -$128M |
|
8758
CALL
Anavex Life Sciences
AVXL
$222M
| – | – |
-22
| Closed | -$11K |
|
|
8759
Anavex Life Sciences
AVXL
$222M
| $0 | ﹤0.01% |
25,163
-32,040
| -56% | -$350K |
|
|
8760
PUT
Anavex Life Sciences
AVXL
$222M
| – | – |
-590
| Closed | -$318K |
|
8761
Axos Financial
AX
$5.45B
| – | – |
-419
| Closed | -$18.9K |
|
8762
PUT
Axogen
AXGN
$2.1B
| – | – |
-5
| Closed | -$8K |
|
8763
CALL
AstraZeneca
AZN
$263B
| – | – |
-3,061
| Closed | -$30.6M |
|
|
8764
AstraZeneca
AZN
$263B
| $0 | ﹤0.01% |
25,732
-85,035
| -77% | -$8.55M |
|
|
8765
PUT
AstraZeneca
AZN
$263B
| – | – |
-1,926
| Closed | -$19.3M |
|
8766
CALL
Azenta
AZTA
$1.26B
| – | – |
-5
| Closed | -$33K |
|
|
8767
Azenta
AZTA
$1.26B
| $0 | ﹤0.01% |
7,071
+1,710
| +32% | +$138K |
|
|
8768
PUT
Azenta
AZTA
$1.26B
| – | – |
-25
| Closed | -$169K |
|
|
AZUL
8769
DELISTED
Azul
AZUL
| – | – |
-47,709
| Closed | -$1.04M |
|
8770
CALL
Alibaba
BABA
$269B
| – | – |
-29,297
| Closed | -$682M |
|
|
8771
Alibaba
BABA
$269B
| $0 | ﹤0.01% |
42,485
-101,145
| -70% | -$24.8M |
|
|
8772
PUT
Alibaba
BABA
$269B
| – | – |
-30,883
| Closed | -$719M |
|
8773
Bally's
BALY
$672M
| – | – |
-10,098
| Closed | -$599K |
|
8774
Banc of California
BANC
$3.28B
| – | – |
-4,823
| Closed | -$89.6K |
|
|
BAND
8775
Bandwidth Inc
BAND
$1.91B
| – | – |
-7,381
| Closed | -$1.14M |
|
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.