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 |
Alibaba
BABA
|
+$120M |
| 2 |
Alphabet (Google) Class A
GOOGL
|
+$93.9M |
| 3 |
Walt Disney
DIS
|
+$71.7M |
| 4 |
KraneShares CSI China Internet ETF
KWEB
|
+$41.7M |
| 5 |
Citigroup
C
|
+$39.4M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$136M |
| 2 |
Amazon
AMZN
|
+$118M |
| 3 |
SPDR Gold Trust
GLD
|
+$56.2M |
| 4 |
Microsoft
MSFT
|
+$52.4M |
| 5 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$45.6M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.33% |
| 2 | Consumer Discretionary | 0.3% |
| 3 | Communication Services | 0.21% |
| 4 | Financials | 0.19% |
| 5 | Healthcare | 0.19% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
1976
CALL
Guidewire Software
GWRE
$11.5B
| $3.11M | ﹤0.01% |
28,500
+18,700
| +191% | +$1.78M |
|
1977
Sarepta Therapeutics
SRPT
$1.66B
| $3.11M | ﹤0.01% |
32,219
+8,660
| +37% | +$831K |
|
1978
PUT
Rambus
RMBS
$10.4B
| $3.1M | ﹤0.01% |
45,500
-42,700
| -48% | -$2.66M |
|
1979
CALL
Frontline
FRO
$8.75B
| $3.1M | ﹤0.01% |
154,800
+91,000
| +143% | +$1.88M |
|
1980
PUT
Elanco Animal Health
ELAN
$12.4B
| $3.08M | ﹤0.01% |
207,000
+49,800
| +32% | +$564K |
|
1981
CALL
Allegion
ALLE
$13B
| $3.08M | ﹤0.01% |
24,300
+21,700
| +835% | +$2.32M |
|
1982
PUT
Lemonade
LMND
$4.62B
| $3.08M | ﹤0.01% |
200,800
+68,400
| +52% | +$1.03M |
|
1983
CALL
Diageo
DEO
$46.2B
| $3.07M | ﹤0.01% |
21,100
-22,600
| -52% | -$3.34M |
|
1984
WEC Energy
WEC
$37.7B
| $3.07M | ﹤0.01% |
36,517
+29,699
| +436% | +$2.45M |
|
1985
Las Vegas Sands
LVS
$30.5B
| $3.07M | ﹤0.01% |
62,436
-30,815
| -33% | -$1.46M |
|
1986
Wolfspeed
WOLF
$1.2B
| $3.06M | ﹤0.01% |
+70,451
| New | +$2.56M |
|
1987
PUT
Lattice Semiconductor
LSCC
$17.6B
| $3.06M | ﹤0.01% |
44,400
+34,500
| +348% | +$2.29M |
|
|
GES
1988
PUT
DELISTED
Guess Inc
GES
| $3.06M | ﹤0.01% |
132,800
+50,000
| +60% | +$1.12M |
|
1989
CALL
Legend Biotech
LEGN
$4.3B
| $3.06M | ﹤0.01% |
50,900
+38,400
| +307% | +$2.43M |
|
1990
CALL
Sprout Social
SPT
$455M
| $3.05M | ﹤0.01% |
49,700
+40,100
| +418% | +$2.11M |
|
1991
PUT
LPL Financial
LPLA
$26.3B
| $3.05M | ﹤0.01% |
13,400
-12,600
| -48% | -$2.83M |
|
1992
iShares Core S&P Total US Stock Market ETF
ITOT
$93.2B
| $3.05M | ﹤0.01% |
+28,979
| New | +$2.84M |
|
1993
CALL
Cincinnati Financial
CINF
$28.3B
| $3.04M | ﹤0.01% |
29,400
+1,900
| +7% | +$193K |
|
|
COOP
1994
CALL
DELISTED
Mr. Cooper
COOP
| $3.04M | ﹤0.01% |
46,700
+27,900
| +148% | +$1.65M |
|
1995
Iovance Biotherapeutics
IOVA
$2.23B
| $3.04M | ﹤0.01% |
374,067
+198,650
| +113% | +$1.04M |
|
1996
PUT
Service Corp International
SCI
$11.4B
| $3.04M | ﹤0.01% |
44,400
+7,600
| +21% | +$458K |
|
1997
CALL
Calix
CALX
$2.27B
| $3.03M | ﹤0.01% |
69,300
+64,600
| +1,374% | +$2.58M |
|
1998
PUT
Prothena Corp
PRTA
$458M
| $3.03M | ﹤0.01% |
83,300
+83,100
| +41,550% | +$3.2M |
|
1999
CALL
Cal-Maine
CALM
$4.28B
| $3.02M | ﹤0.01% |
52,700
+35,400
| +205% | +$1.75M |
|
2000
PUT
HF Sinclair
DINO
$15.9B
| $3.02M | ﹤0.01% |
54,400
+8,900
| +20% | +$485K |
|
Similar funds
Simplex Trading's Q4 2023 Portfolio in Review
As of Q4 2023, Simplex Trading held 10,333 positions worth $156B, up 23% from $127B the previous quarter. Its ten largest holdings account for 42% of the portfolio.
Simplex Trading deployed $15.1B of net new capital in Q4 2023, opening 1,639 new positions and adding to 3,920 existing holdings. Its largest new stake was Walt Disney: 812,984 shares worth $73.4M.
By sector, the portfolio is most concentrated in Technology at 0.33% of assets, down from 0.44% a quarter earlier, followed by Consumer Discretionary and Communication Services.
On the sell side, the largest reduction was iShares 20+ Year Treasury Bond ETF, an estimated $136M trimmed.
- Simplex Trading's largest Q4 2023 buy was Walt Disney: 812,984 shares worth $73.4M.
- Simplex Trading added most to Alibaba in Q4 2023, an estimated $120M increase.
- Simplex Trading's biggest Q4 2023 reduction was iShares 20+ Year Treasury Bond ETF, cutting an estimated $136M.
- Simplex Trading fully exited Amazon in Q4 2023, selling an estimated $118M.
- Simplex Trading's ten largest holdings make up 42% of its $156B portfolio in Q4 2023.
- Simplex Trading opened 1,639 new positions and closed 1,508 in Q4 2023.
- Simplex Trading's portfolio value rose 23% quarter-over-quarter to $156B.
Based on Simplex Trading's 13F filing for Q4 2023, filed 2 Feb 2024.