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 | |
|---|---|---|---|---|---|---|
3551
PUT
Ironwood Pharmaceuticals
IRWD
$626M
| $439K | ﹤0.01% |
393
+227
| +137% | +$2.4K |
|
3552
PUT
Jacobs Solutions
J
$16.6B
| $439K | ﹤0.01% |
41
-67
| -62% | -$6.4K |
|
|
NSA
3553
CALL
DELISTED
National Storage Affiliates Trust
NSA
| $439K | ﹤0.01% |
110
+64
| +139% | +$2.44K |
|
3554
Universal Display
OLED
$3.85B
| $439K | ﹤0.01% |
1,857
+1,420
| +325% | +$328K |
|
|
LL
3555
CALL
DELISTED
LL Flooring Holdings, Inc.
LL
| $439K | ﹤0.01% |
+175
| New | +$4.85K |
|
3556
CALL
Altimmune
ALT
$581M
| $438K | ﹤0.01% |
+310
| New | +$5.01K |
|
|
SAFM
3557
DELISTED
Sanderson Farms Inc
SAFM
| $438K | ﹤0.01% |
2,816
+2,420
| +611% | +$358K |
|
3558
PUT
Equitable Holdings
EQH
$13.5B
| $437K | ﹤0.01% |
134
-305
| -69% | -$8.79K |
|
3559
CALL
FormFactor
FORM
$6.88B
| $437K | ﹤0.01% |
97
+42
| +76% | +$1.91K |
|
3560
CALL
Knowles
KN
$3.07B
| $437K | ﹤0.01% |
209
-250
| -54% | -$5.09K |
|
|
DSKE
3561
CALL
DELISTED
Daseke, Inc. Common Stock
DSKE
| $437K | ﹤0.01% |
515
+15
| +3% | +$92 |
|
3562
PUT
Invesco
IVZ
$13B
| $436K | ﹤0.01% |
173
-41
| -19% | -$919 |
|
|
MASI
3563
CALL
DELISTED
Masimo
MASI
| $436K | ﹤0.01% |
19
-6
| -24% | -$1.51K |
|
|
ICPT
3564
PUT
DELISTED
Intercept Pharmaceuticals, Inc.
ICPT
| $436K | ﹤0.01% |
189
-89
| -32% | -$2.48K |
|
3565
Acacia Research
ACTG
$447M
| $435K | ﹤0.01% |
65,539
+50,671
| +341% | +$319K |
|
3566
CALL
ADT
ADT
$5.38B
| $435K | ﹤0.01% |
516
-568
| -52% | -$4.92K |
|
|
SHYF
3567
PUT
DELISTED
The Shyft Group
SHYF
| $435K | ﹤0.01% |
117
+3
| +3% | +$101 |
|
3568
CALL
TETRA Technologies
TTI
$1.07B
| $435K | ﹤0.01% |
1,815
+1,765
| +3,530% | +$3.8K |
|
3569
PUT
Essex Property Trust
ESS
$18.9B
| $434K | ﹤0.01% |
16
-16
| -50% | -$4.15K |
|
3570
Lufax Holding
LU
$1.33B
| $434K | ﹤0.01% |
7,478
+6,579
| +732% | +$404K |
|
3571
Ribbon Communications
RBBN
$361M
| $434K | ﹤0.01% |
52,940
+36,933
| +231% | +$306K |
|
3572
CALL
Reynolds Consumer Products
REYN
$5.44B
| $434K | ﹤0.01% |
146
+130
| +813% | +$3.84K |
|
3573
PUT
ADMA Biologics
ADMA
$2.04B
| $433K | ﹤0.01% |
2,464
+1,742
| +241% | +$3.99K |
|
|
MSB
3574
PUT
Mesabi Trust
MSB
$300M
| $433K | ﹤0.01% |
144
+142
| +7,100% | +$3.98K |
|
|
HYRE
3575
PUT
DELISTED
HyreCar Inc. Common Stock
HYRE
| $433K | ﹤0.01% |
442
+327
| +284% | +$3.22K |
|
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.