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 | |
|---|---|---|---|---|---|---|
651
PUT
Five Below
FIVE
$11.3B
| $6.43M | 0.01% |
337
-12
| -3% | -$2.26K |
|
652
CALL
Generac Holdings
GNRC
$12.2B
| $6.42M | 0.01% |
196
+125
| +176% | +$36.8K |
|
653
CALL
Exelon
EXC
$48.6B
| $6.42M | 0.01% |
2,057
+75
| +4% | +$2.25K |
|
|
PPLC
654
PUT
DELISTED
PortfolioPlus S&P 500 ETF
PPLC
| $6.41M | 0.01% |
998
-159
| -14% | -$1.02M |
|
655
PUT
Kimberly-Clark
KMB
$36.3B
| $6.4M | 0.01% |
460
-345
| -43% | -$45.8K |
|
656
Lucid Motors
LCID
$2.48B
| $6.39M | 0.01% |
+27,578
| New | +$7.37M |
|
657
CALL
Halliburton
HAL
$27.9B
| $6.38M | 0.01% |
2,974
+605
| +26% | +$12.7K |
|
658
PUT
Centene
CNC
$31.3B
| $6.38M | 0.01% |
+998
| New | +$61.8K |
|
659
PUT
Affirm
AFRM
$24B
| $6.36M | 0.01% |
+899
| New | +$87.4K |
|
660
PUT
Novartis
NVS
$295B
| $6.35M | 0.01% |
743
+284
| +62% | +$25.5K |
|
661
PUT
Trip.com Group
TCOM
$27.7B
| $6.35M | 0.01% |
1,602
-879
| -35% | -$32.5K |
|
|
AZPN
662
PUT
DELISTED
ASPEN TECHNOLOGY INC
AZPN
| $6.34M | 0.01% |
439
+117
| +36% | +$1.69M |
|
663
PUT
Corteva
CTVA
$59.2B
| $6.33M | 0.01% |
1,359
+1,303
| +2,327% | +$57.6K |
|
664
PUT
C3.ai
AI
$1.29B
| $6.33M | 0.01% |
961
+451
| +88% | +$52.5K |
|
665
CALL
Zebra Technologies
ZBRA
$12.5B
| $6.31M | 0.01% |
130
+97
| +294% | +$43.3K |
|
666
PUT
Tractor Supply
TSCO
$16B
| $6.27M | 0.01% |
1,770
-455
| -20% | -$14.5K |
|
|
RWT
667
PUT
Redwood Trust
RWT
$622M
| $6.25M | 0.01% |
6,003
-311
| -5% | -$2.99K |
|
668
PUT
BioMarin Pharmaceuticals
BMRN
$11.4B
| $6.24M | 0.01% |
827
+185
| +29% | +$15.1K |
|
669
PUT
Chegg
CHGG
$114M
| $6.24M | 0.01% |
728
+88
| +14% | +$8.38K |
|
|
TBHC
670
PUT
DELISTED
The Brand House Collective
TBHC
| $6.21M | 0.01% |
2,212
-215
| -9% | -$5.37K |
|
671
PUT
Hasbro
HAS
$12.5B
| $6.2M | 0.01% |
645
-363
| -36% | -$34.5K |
|
672
CALL
Revolve Group
RVLV
$1.77B
| $6.19M | 0.01% |
1,378
+638
| +86% | +$26K |
|
673
CALL
SS&C Technologies
SSNC
$17.8B
| $6.18M | 0.01% |
885
+594
| +204% | +$40.1K |
|
|
FL
674
PUT
DELISTED
Foot Locker
FL
| $6.18M | 0.01% |
+1,099
| New | +$55.8K |
|
675
CALL
3D Systems Corp
DDD
$425M
| $6.18M | 0.01% |
2,252
-19
| -0.8% | -$628 |
|
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.