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 | |
|---|---|---|---|---|---|---|
2476
ImmunityBio
IBRX
$7.44B
| $936K | ﹤0.01% |
39,460
-28,528
| -42% | -$740K |
|
2477
CALL
Nu Skin
NUS
$247M
| $936K | ﹤0.01% |
177
+161
| +1,006% | +$8.77K |
|
2478
CALL
Brookfield
BN
$102B
| $934K | ﹤0.01% |
392
-148
| -27% | -$3.3K |
|
2479
CALL
NNN REIT
NNN
$9.39B
| $934K | ﹤0.01% |
212
-160
| -43% | -$6.7K |
|
2480
CALL
Hain Celestial
HAIN
$47.8M
| $933K | ﹤0.01% |
214
-147
| -41% | -$6.25K |
|
2481
CALL
Tyler Technologies
TYL
$12.2B
| $933K | ﹤0.01% |
22
-5
| -19% | -$2.16K |
|
2482
PUT
BlackLine
BL
$1.69B
| $932K | ﹤0.01% |
86
+42
| +95% | +$5.24K |
|
2483
PUT
Pitney Bowes
PBI
$2.42B
| $932K | ﹤0.01% |
1,132
-1,261
| -53% | -$10.8K |
|
2484
CALL
PROG Holdings
PRG
$1.75B
| $932K | ﹤0.01% |
218
+104
| +91% | +$5.19K |
|
2485
CALL
Tradeweb Markets
TW
$21.3B
| $932K | ﹤0.01% |
126
+14
| +13% | +$962 |
|
2486
PUT
Yeti Holdings
YETI
$3.82B
| $931K | ﹤0.01% |
+129
| New | +$9.19K |
|
2487
Cadence Design Systems
CDNS
$90B
| $930K | ﹤0.01% |
+6,793
| New | +$911K |
|
2488
CALL
Pinnacle West Capital
PNW
$12.9B
| $927K | ﹤0.01% |
114
+9
| +9% | +$696 |
|
2489
Yum! Brands
YUM
$41B
| $926K | ﹤0.01% |
+8,563
| New | +$906K |
|
2490
PUT
Sasol
SSL
$7.58B
| $925K | ﹤0.01% |
639
-145
| -18% | -$1.85K |
|
|
REGI
2491
PUT
DELISTED
Renewable Energy Group, Inc.
REGI
| $924K | ﹤0.01% |
140
+19
| +16% | +$1.63K |
|
2492
PUT
Amphenol
APH
$188B
| $923K | ﹤0.01% |
280
+80
| +40% | +$2.6K |
|
2493
CALL
Ryman Hospitality Properties
RHP
$8.4B
| $922K | ﹤0.01% |
119
-46
| -28% | -$3.4K |
|
2494
HF Sinclair
DINO
$15.9B
| $920K | ﹤0.01% |
25,735
-1,007
| -4% | -$33.6K |
|
2495
CALL
Western Midstream Partners
WES
$19.6B
| $920K | ﹤0.01% |
495
-89
| -15% | -$1.51K |
|
|
CALY
2496
Callaway Golf Company
CALY
$3.26B
| $919K | ﹤0.01% |
34,388
+132
| +0.4% | +$3.73K |
|
|
SII
2497
CALL
Sprott
SII
$2.65B
| $919K | ﹤0.01% |
242
+21
| +10% | +$731 |
|
2498
PUT
ProShares Ultra S&P500
SSO
$7.71B
| $919K | ﹤0.01% |
1,432
-5,020
| -78% | -$122K |
|
2499
Xos
XOS
$27.7M
| $919K | ﹤0.01% |
+3,091
| New | +$1M |
|
|
NNDM
2500
CALL
Nano Dimension
NNDM
$309M
| $918K | ﹤0.01% |
1,069
-276
| -21% | -$3.17K |
|
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.