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 | |
|---|---|---|---|---|---|---|
1676
CALL
Eastern Bankshares
EBC
$5.25B
| $1.87M | ﹤0.01% |
968
+915
| +1,726% | +$15.9K |
|
|
HOME
1677
PUT
DELISTED
At Home Group Inc.
HOME
| $1.86M | ﹤0.01% |
650
-129
| -17% | -$3.24K |
|
|
VCVC
1678
CALL
DELISTED
10X Capital Venture Acquisition Corp
VCVC
| $1.86M | ﹤0.01% |
+1,864
| New | +$21.1K |
|
1679
PUT
CoreCivic
CXW
$3.1B
| $1.86M | ﹤0.01% |
2,059
+504
| +32% | +$3.88K |
|
1680
TripAdvisor
TRIP
$1.59B
| $1.86M | ﹤0.01% |
34,646
-4,731
| -12% | -$203K |
|
1681
PUT
Spruce Power Holding Corp
SPRU
$39.9M
| $1.86M | ﹤0.01% |
259
+17
| +7% | +$2.25K |
|
1682
PUT
Takeda Pharmaceutical
TAK
$55.1B
| $1.86M | ﹤0.01% |
1,020
+745
| +271% | +$13.4K |
|
|
IAA
1683
CALL
DELISTED
IAA, Inc. Common Stock
IAA
| $1.86M | ﹤0.01% |
337
+308
| +1,062% | +$18.3K |
|
1684
CALL
Republic Services
RSG
$66.7B
| $1.86M | ﹤0.01% |
187
+114
| +156% | +$10.7K |
|
|
BFX
1685
DELISTED
BowFlex Inc.
BFX
| $1.86M | ﹤0.01% |
118,796
+91,843
| +341% | +$1.97M |
|
|
CTLT
1686
CALL
DELISTED
CATALENT, INC.
CTLT
| $1.85M | ﹤0.01% |
176
+46
| +35% | +$5.13K |
|
1687
PUT
Joby Aviation
JOBY
$6.82B
| $1.85M | ﹤0.01% |
+1,825
| New | +$22.1K |
|
1688
PUT
Sibanye-Stillwater
SBSW
$5.92B
| $1.85M | ﹤0.01% |
1,037
-575
| -36% | -$10.1K |
|
1689
CALL
Wabtec
WAB
$51.1B
| $1.85M | ﹤0.01% |
234
+93
| +66% | +$7.22K |
|
1690
Roblox
RBLX
$34B
| $1.85M | ﹤0.01% |
+28,537
| New | +$1.99M |
|
1691
CALL
Bloom Energy
BE
$52.6B
| $1.85M | ﹤0.01% |
683
-608
| -47% | -$19.8K |
|
1692
CALL
MGIC Investment
MTG
$6.27B
| $1.84M | ﹤0.01% |
1,332
-962
| -42% | -$12.3K |
|
1693
PUT
ProShares Ultra Bloomberg Natural Gas
BOIL
$417M
| $1.84M | ﹤0.01% |
2
-10
| -83% | -$47.4K |
|
|
ETWO
1694
CALL
DELISTED
E2open Parent Holdings
ETWO
| $1.84M | ﹤0.01% |
+1,851
| New | +$18.9K |
|
1695
PUT
Ericsson
ERIC
$30.7B
| $1.84M | ﹤0.01% |
1,397
-410
| -23% | -$5.22K |
|
1696
Sonos
SONO
$1.75B
| $1.84M | ﹤0.01% |
49,179
-54,881
| -53% | -$1.85M |
|
1697
PUT
Herbalife
HLF
$1.23B
| $1.84M | ﹤0.01% |
415
-84
| -17% | -$4.14K |
|
|
AGC
1698
CALL
DELISTED
Altimeter Growth Corp
AGC
| $1.84M | ﹤0.01% |
+1,573
| New | +$21.1K |
|
|
DM
1699
CALL
DELISTED
Desktop Metal, Inc.
DM
| $1.84M | ﹤0.01% |
123
-68
| -36% | -$15K |
|
1700
iShares MSCI Taiwan ETF
EWT
$10B
| $1.84M | ﹤0.01% |
30,636
-13,847
| -31% | -$805K |
|
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.