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 | |
|---|---|---|---|---|---|---|
776
PUT
Interactive Brokers
IBKR
$40.9B
| $5.3M | 0.01% |
2,904
+2,344
| +419% | +$42.2K |
|
777
CALL
Diageo
DEO
$46.2B
| $5.29M | 0.01% |
322
-13
| -4% | -$2.13K |
|
778
CALL
Nokia
NOK
$50.8B
| $5.26M | 0.01% |
13,289
+7,833
| +144% | +$32.7K |
|
779
CALL
Genuine Parts
GPC
$17.1B
| $5.26M | 0.01% |
+455
| New | +$48.4K |
|
780
PUT
Dynatrace
DT
$12.1B
| $5.25M | 0.01% |
1,089
+254
| +30% | +$12.3K |
|
781
PUT
Sunrun
RUN
$2.37B
| $5.25M | 0.01% |
+1,577
| New | +$110K |
|
782
Cisco
CSCO
$450B
| $5.24M | 0.01% |
101,382
-156,312
| -61% | -$7.34M |
|
783
CALL
GSK
GSK
$103B
| $5.23M | 0.01% |
1,173
-574
| -33% | -$26.1K |
|
784
Bristol-Myers Squibb
BMY
$127B
| $5.22M | 0.01% |
82,740
-33,996
| -29% | -$2.12M |
|
785
CALL
Innovative Industrial Properties
IIPR
$1.78B
| $5.21M | 0.01% |
289
+193
| +201% | +$37K |
|
786
PUT
AvalonBay Communities
AVB
$27.1B
| $5.2M | 0.01% |
282
+143
| +103% | +$25K |
|
787
CALL
Southern Company
SO
$110B
| $5.2M | 0.01% |
837
-761
| -48% | -$45.6K |
|
788
PUT
Crown Castle
CCI
$32.7B
| $5.2M | 0.01% |
302
-812
| -73% | -$130K |
|
789
CALL
Five Below
FIVE
$11.2B
| $5.19M | 0.01% |
272
+87
| +47% | +$16.4K |
|
790
PUT
F5
FFIV
$22.1B
| $5.17M | 0.01% |
248
-162
| -40% | -$31.9K |
|
791
CALL
BILL Holdings
BILL
$4.33B
| $5.17M | 0.01% |
355
+273
| +333% | +$40.9K |
|
792
CALL
Conagra Brands
CAG
$7.07B
| $5.15M | 0.01% |
+1,371
| New | +$48.5K |
|
793
Datadog
DDOG
$87.9B
| $5.15M | 0.01% |
61,834
+28,743
| +87% | +$2.77M |
|
794
PUT
BJs Wholesale Club
BJ
$11.9B
| $5.15M | 0.01% |
1,148
+408
| +55% | +$17.1K |
|
795
PUT
NCR Voyix
VYX
$1.06B
| $5.15M | 0.01% |
2,210
+1,599
| +262% | +$35.2K |
|
796
PUT
Bloom Energy
BE
$52.6B
| $5.14M | 0.01% |
1,902
-125
| -6% | -$4.08K |
|
|
797
CALL
Interactive Brokers
IBKR
$40.9B
| $5.14M | 0.01% |
2,816
+1,500
| +114% | +$27K |
|
798
CALL
LyondellBasell Industries
LYB
$19.5B
| $5.14M | 0.01% |
494
-356
| -42% | -$35.3K |
|
|
MMP
799
CALL
DELISTED
Magellan Midstream Partners, L.P.
MMP
| $5.14M | 0.01% |
1,185
-38
| -3% | -$1.66K |
|
800
PUT
Royal Bank of Canada
RY
$291B
| $5.13M | 0.01% |
556
+499
| +875% | +$43.4K |
|
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.