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 | |
|---|---|---|---|---|---|---|
|
MCFE
1926
DELISTED
McAfee Corp. Class A Common Stock
MCFE
| $1.52M | ﹤0.01% |
66,877
+58,565
| +705% | +$1.22M |
|
|
MGLN
1927
PUT
DELISTED
Magellan Health Services, Inc.
MGLN
| $1.52M | ﹤0.01% |
163
+162
| +16,200% | +$15.2K |
|
1928
eHealth
EHTH
$42.5M
| $1.52M | ﹤0.01% |
20,875
+13,721
| +192% | +$877K |
|
1929
CALL
argenx
ARGX
$57.4B
| $1.51M | ﹤0.01% |
55
-19
| -26% | -$6K |
|
1930
CALL
Axalta
AXTA
$7.01B
| $1.51M | ﹤0.01% |
512
-347
| -40% | -$9.94K |
|
1931
PUT
Rapid7
RPD
$634M
| $1.51M | ﹤0.01% |
203
-126
| -38% | -$10.5K |
|
1932
RTX Corp
RTX
$287B
| $1.51M | ﹤0.01% |
19,597
+19,364
| +8,311% | +$1.41M |
|
|
XEC
1933
CALL
DELISTED
CIMAREX ENERGY CO
XEC
| $1.51M | ﹤0.01% |
255
-447
| -64% | -$23.9K |
|
1934
CALL
Cardlytics
CDLX
$21M
| $1.51M | ﹤0.01% |
14
-8
| -36% | -$10.6K |
|
|
HA
1935
CALL
DELISTED
Hawaiian Holdings, Inc.
HA
| $1.51M | ﹤0.01% |
567
+254
| +81% | +$6.02K |
|
|
ROIC
1936
PUT
DELISTED
Retail Opportunity Investments Corp.
ROIC
| $1.51M | ﹤0.01% |
952
+860
| +935% | +$13.2K |
|
1937
CALL
MasTec
MTZ
$26.7B
| $1.51M | ﹤0.01% |
161
+39
| +32% | +$3.34K |
|
1938
CALL
Bumble
BMBL
$367M
| $1.5M | ﹤0.01% |
+241
| New | +$16.2K |
|
1939
Perion Network
PERI
$367M
| $1.5M | ﹤0.01% |
83,961
-5,190
| -6% | -$93.7K |
|
1940
PUT
Cirrus Logic
CRUS
$6.74B
| $1.5M | ﹤0.01% |
177
-255
| -59% | -$22.1K |
|
|
BLDP
1941
PUT
Ballard Power Systems
BLDP
$874M
| $1.5M | ﹤0.01% |
616
+302
| +96% | +$9.03K |
|
1942
PUT
Danaos Corp
DAC
$2.55B
| $1.5M | ﹤0.01% |
302
+295
| +4,214% | +$11K |
|
|
INFN
1943
CALL
DELISTED
Infinera Corporation Common Stock
INFN
| $1.5M | ﹤0.01% |
1,555
-174
| -10% | -$1.71K |
|
|
OZON
1944
DELISTED
Ozon Holdings PLC American Depositary Shares, each ADS representing one ordinary share
OZON
| $1.5M | ﹤0.01% |
26,711
+20,371
| +321% | +$1.12M |
|
|
SAND
1945
CALL
DELISTED
Sandstorm Gold
SAND
| $1.5M | ﹤0.01% |
2,200
+769
| +54% | +$5.16K |
|
|
TGNA
1946
DELISTED
TEGNA Inc
TGNA
| $1.49M | ﹤0.01% |
79,381
+75,501
| +1,946% | +$1.32M |
|
|
1947
PUT
Perion Network
PERI
$367M
| $1.49M | ﹤0.01% |
834
-511
| -38% | -$9.23K |
|
|
TWOU
1948
PUT
DELISTED
2U Inc
TWOU
| $1.49M | ﹤0.01% |
13
+1
| +8% | +$1.27K |
|
1949
PUT
Academy Sports + Outdoors
ASO
$2.89B
| $1.49M | ﹤0.01% |
552
+457
| +481% | +$10.9K |
|
1950
CALL
Huntington Bancshares
HBAN
$35.1B
| $1.49M | ﹤0.01% |
947
+128
| +16% | +$1.92K |
|
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.