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 |
GE Aerospace
GE
|
+$36M |
| 2 |
Advanced Micro Devices
AMD
|
+$19.4M |
| 3 |
iShares MSCI EAFE ETF
EFA
|
+$10.2M |
| 4 |
Micron Technology
MU
|
+$6.31M |
| 5 |
Alibaba
BABA
|
+$6.19M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
NVIDIA
NVDA
|
+$25.9M |
| 2 |
SPDR Gold Trust
GLD
|
+$15.3M |
| 3 |
Amazon
AMZN
|
+$9.53M |
| 4 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$9.03M |
| 5 |
State Street Technology Select Sector SPDR ETF
XLK
|
+$7.73M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.49% |
| 2 | Consumer Discretionary | 0.39% |
| 3 | Communication Services | 0.27% |
| 4 | Healthcare | 0.25% |
| 5 | Financials | 0.25% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
951
CALL
United Parks & Resorts
PRKS
$2.08B
| $6.92M | 0.01% |
135,100
+1,400
| +1% | +$70.5K |
|
952
PUT
Nexstar Media Group
NXST
$5.53B
| $6.9M | 0.01% |
45,600
| – | – |
|
|
ATVI
953
DELISTED
Activision Blizzard
ATVI
| $6.9M | 0.01% |
73,444
-12,927
| -15% | -$1.08M |
|
954
PUT
Dave & Buster's
PLAY
$339M
| $6.88M | 0.01% |
168,800
+2,400
| +1% | +$86.8K |
|
955
CALL
Stellantis
STLA
$16.7B
| $6.85M | 0.01% |
345,500
| – | – |
|
956
PUT
Parker-Hannifin
PH
$124B
| $6.85M | 0.01% |
22,300
+500
| +2% | +$149K |
|
|
GTM
957
PUT
ZoomInfo Technologies
GTM
$849M
| $6.83M | 0.01% |
132,900
+100
| +0.1% | +$5.98K |
|
958
CALL
Trimble
TRMB
$11.7B
| $6.83M | 0.01% |
82,800
| – | – |
|
959
CALL
Sonos
SONO
$1.73B
| $6.82M | 0.01% |
191,200
+25,600
| +15% | +$922K |
|
|
SRNE
960
CALL
DELISTED
Sorrento Therapeutics, Inc.
SRNE
| $6.81M | 0.01% |
620,000
+36,100
| +6% | +$306K |
|
961
PUT
Albemarle
ALB
$13.8B
| $6.81M | 0.01% |
39,600
+800
| +2% | +$171K |
|
962
CALL
Suncor Energy
SU
$78.4B
| $6.81M | 0.01% |
279,100
+200
| +0.1% | +$4K |
|
963
SoFi Technologies
SOFI
$21.4B
| $6.8M | 0.01% |
372,678
+18,794
| +5% | +$295K |
|
964
CALL
Vroom Inc
VRM
$38.1M
| $6.79M | 0.01% |
1,996
-2
| -0.1% | -$5.09K |
|
965
PUT
Truist Financial
TFC
$62.5B
| $6.77M | 0.01% |
120,213
+645
| +0.5% | +$36K |
|
966
Shopify
SHOP
$145B
| $6.75M | 0.01% |
46,320
+1,870
| +4% | +$280K |
|
|
KL
967
CALL
DELISTED
Kirkland Lake Gold Ltd Ordinary
KL
| $6.75M | 0.01% |
175,900
-400
| -0.2% | -$16.2K |
|
968
Southwest Airlines
LUV
$21.9B
| $6.73M | 0.01% |
124,961
-7,193
| -5% | -$363K |
|
969
PUT
Tractor Supply
TSCO
$15.9B
| $6.71M | 0.01% |
178,500
+500
| +0.3% | +$19.4K |
|
970
Las Vegas Sands
LVS
$30.5B
| $6.7M | 0.01% |
126,147
-4,110
| -3% | -$176K |
|
971
Chewy
CHWY
$8.38B
| $6.7M | 0.01% |
83,102
-6,910
| -8% | -$572K |
|
972
PUT
Floor & Decor
FND
$5.73B
| $6.69M | 0.01% |
63,300
| – | – |
|
973
Norwegian Cruise Line
NCLH
$8.59B
| $6.68M | 0.01% |
226,519
-25,321
| -10% | -$644K |
|
974
PUT
Aptiv
APTV
$11.9B
| $6.67M | 0.01% |
42,000
| – | – |
|
975
PUT
Cameco
CCJ
$38.9B
| $6.61M | 0.01% |
341,200
+8,000
| +2% | +$151K |
|
Similar funds
Simplex Trading's Q3 2021 Portfolio in Review
As of Q3 2021, Simplex Trading held 10,062 positions worth $107B, up 3.4% from $104B the previous quarter. Its ten largest holdings account for 41% of the portfolio.
Trading was light in Q3 2021: portfolio turnover was 3.5%. Simplex Trading opened 86 new positions and exited 271, leaving the 10,062-position portfolio largely intact.
By sector, the portfolio is most concentrated in Technology at 0.49% of assets, up from 0.47% a quarter earlier, followed by Consumer Discretionary and Communication Services.
- Simplex Trading's largest Q3 2021 buy was Olo Inc: 143,230 shares worth $4.91M.
- Simplex Trading added most to GE Aerospace in Q3 2021, an estimated $36M increase.
- Simplex Trading's biggest Q3 2021 reduction was NVIDIA, cutting an estimated $25.9M.
- Simplex Trading fully exited Amazon in Q3 2021, selling an estimated $9.53M.
- Simplex Trading's ten largest holdings make up 41% of its $107B portfolio in Q3 2021.
- Simplex Trading opened 86 new positions and closed 271 in Q3 2021.
- Simplex Trading's portfolio value rose 3.4% quarter-over-quarter to $107B.
Based on Simplex Trading's 13F filing for Q3 2021, filed 28 Oct 2021.