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 | |
|---|---|---|---|---|---|---|
201
CALL
Illumina
ILMN
$29.1B
| $31.8M | 0.06% |
851
-35
| -4% | -$14.3K |
|
202
CALL
Western Digital
WDC
$189B
| $31.8M | 0.06% |
6,301
+1,160
| +23% | +$54.2K |
|
203
CALL
iShares MSCI Australia ETF
EWA
$1.34B
| $31.5M | 0.06% |
37,367
+3,656
| +11% | +$90.9K |
|
204
CALL
Abbott
ABT
$174B
| $31.4M | 0.06% |
+2,622
| New | +$311K |
|
205
CALL
Zscaler
ZS
$24B
| $31.3M | 0.06% |
1,823
+629
| +53% | +$125K |
|
206
CALL
Zillow
Z
$7.29B
| $31.2M | 0.06% |
2,400
-1,935
| -45% | -$287K |
|
207
CALL
iShares Core MSCI Emerging Markets ETF
IEMG
$154B
| $31.2M | 0.06% |
4,852
+4
| +0.1% | +$263 |
|
208
PUT
WIX.com
WIX
$2.14B
| $30.9M | 0.06% |
1,106
-322
| -23% | -$92K |
|
|
TYNS
209
PUT
DELISTED
Direxion Daily 7-10 Year Treasury Bear 1X Shares
TYNS
| $30.6M | 0.06% |
3,372
+1,282
| +61% | +$11.6M |
|
210
CALL
American Tower
AMT
$76.1B
| $30.5M | 0.05% |
1,276
+512
| +67% | +$114K |
|
211
CALL
Lucid Motors
LCID
$2.86B
| $30.4M | 0.05% |
+1,313
| New | +$351K |
|
212
PUT
lululemon athletica
LULU
$13.2B
| $30.4M | 0.05% |
992
-299
| -23% | -$98.2K |
|
213
PUT
VanEck Durable High Dividend ETF
DURA
$38.1M
| $30.2M | 0.05% |
1,843
-1,100
| -37% | -$31.7K |
|
|
X
214
PUT
DELISTED
US Steel
X
| $30.1M | 0.05% |
11,490
+2,286
| +25% | +$45.1K |
|
215
CALL
Novavax
NVAX
$1.33B
| $30M | 0.05% |
1,656
-508
| -23% | -$101K |
|
216
CALL
Proshares UltraShort Technology
REW
$3.27M
| $30M | 0.05% |
1,522
+852
| +127% | +$181K |
|
217
PUT
Southwest Airlines
LUV
$23.8B
| $29.6M | 0.05% |
4,843
+580
| +14% | +$30.9K |
|
218
CALL
Bristol-Myers Squibb
BMY
$124B
| $29.5M | 0.05% |
4,666
+262
| +6% | +$16.3K |
|
219
CALL
Trade Desk
TTD
$8.58B
| $29M | 0.05% |
4,450
-270
| -6% | -$20.9K |
|
220
CALL
Direxion Daily Technology Bull 3x ETF
TECL
$5.6B
| $28.9M | 0.05% |
20,200
-89,890
| -82% | -$3.74M |
|
221
CALL
Etsy
ETSY
$7.97B
| $28.4M | 0.05% |
1,408
-109
| -7% | -$22.8K |
|
222
PUT
Elevance Health
ELV
$85.3B
| $28.4M | 0.05% |
791
+212
| +37% | +$68.2K |
|
223
PUT
eBay
EBAY
$50.2B
| $28.4M | 0.05% |
+4,636
| New | +$269K |
|
224
PUT
Strategy Inc
MSTR
$37B
| $28.3M | 0.05% |
4,170
+2,170
| +109% | +$153K |
|
|
ATVI
225
PUT
DELISTED
Activision Blizzard
ATVI
| $28.2M | 0.05% |
3,031
-2,738
| -47% | -$257K |
|
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.