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 | |
|---|---|---|---|---|---|---|
3976
PUT
MACOM Technology Solutions
MTSI
$19B
| $381K | ﹤0.01% |
4,100
-1,000
| -20% | -$82.2K |
|
|
SRCL
3977
CALL
DELISTED
Stericycle Inc
SRCL
| $381K | ﹤0.01% |
7,700
-2,100
| -21% | -$94.2K |
|
|
AIV
3978
Aimco
AIV
$375M
| $380K | ﹤0.01% |
48,625
+4,430
| +10% | +$29.9K |
|
3979
PUT
Cogent Communications
CCOI
$649M
| $380K | ﹤0.01% |
5,000
+1,700
| +52% | +$114K |
|
3980
Remitly
RELY
$4.91B
| $380K | ﹤0.01% |
+19,591
| New | +$439K |
|
3981
CALL
Suburban Propane Partners
SPH
$1.24B
| $380K | ﹤0.01% |
21,400
-19,000
| -47% | -$324K |
|
3982
CALL
Donaldson
DCI
$11.1B
| $379K | ﹤0.01% |
5,800
+4,900
| +544% | +$299K |
|
3983
PUT
Legend Biotech
LEGN
$3.68B
| $379K | ﹤0.01% |
6,300
+3,400
| +117% | +$215K |
|
|
RYZB
3984
PUT
DELISTED
RayzeBio, Inc. Common Stock
RYZB
| $379K | ﹤0.01% |
+6,100
| New | +$152K |
|
|
ARI
3985
PUT
Apollo Commercial Real Estate
ARI
$881M
| $378K | ﹤0.01% |
32,200
-400
| -1% | -$4.28K |
|
|
BLDP
3986
CALL
Ballard Power Systems
BLDP
$808M
| $378K | ﹤0.01% |
102,200
+19,800
| +24% | +$70.4K |
|
3987
Global Ship Lease
GSL
$1.57B
| $378K | ﹤0.01% |
19,075
+5,379
| +39% | +$97.9K |
|
3988
CALL
Brookfield Infrastructure
BIPC
$5.23B
| $377K | ﹤0.01% |
10,700
+4,700
| +78% | +$150K |
|
3989
Genius Sports
GENI
$1.95B
| $377K | ﹤0.01% |
61,088
+23,053
| +61% | +$124K |
|
3990
Option Care Health
OPCH
$3.53B
| $377K | ﹤0.01% |
+11,193
| New | +$344K |
|
3991
PUT
Fortuna Silver Mines
FSM
$2.55B
| $376K | ﹤0.01% |
97,600
+10,600
| +12% | +$35.4K |
|
3992
CALL
Harmony Gold Mining
HMY
$9.7B
| $376K | ﹤0.01% |
61,300
-151,000
| -71% | -$794K |
|
3993
PUT
Vanguard Total International Stock ETF
VXUS
$153B
| $376K | ﹤0.01% |
6,500
+5,800
| +829% | +$317K |
|
3994
PUT
Zumiez
ZUMZ
$347M
| $376K | ﹤0.01% |
18,500
+4,700
| +34% | +$84.2K |
|
3995
PUT
2x Bitcoin ETF
BITX
$899M
| $375K | ﹤0.01% |
16,500
+16,200
| +5,400% | +$297K |
|
|
DFTX
3996
CALL
Definium Therapeutics
DFTX
$5.57B
| $375K | ﹤0.01% |
323,400
+8,200
| +3% | +$24.7K |
|
3997
Microvision
MVIS
$86.6M
| $375K | ﹤0.01% |
141,018
-11,326
| -7% | -$26K |
|
3998
PUT
Replimune Group
REPL
$449M
| $375K | ﹤0.01% |
44,500
-56,800
| -56% | -$659K |
|
|
DENN
3999
PUT
DELISTED
Denny's
DENN
| $374K | ﹤0.01% |
34,400
-100
| -0.3% | -$940 |
|
4000
CALL
Rayonier
RYN
$6.64B
| $374K | ﹤0.01% |
12,345
-2,094
| -15% | -$56K |
|
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.