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 | |
|---|---|---|---|---|---|---|
5826
PUT
Aviat Networks
AVNW
$271M
| $65K | ﹤0.01% |
2,000
-1,100
| -35% | -$32.8K |
|
|
CMRC
5827
PUT
Commerce.com Inc Series 1
CMRC
$257M
| $65K | ﹤0.01% |
6,700
-400
| -6% | -$3.72K |
|
5828
CALL
Citi Trends
CTRN
$559M
| $65K | ﹤0.01% |
2,300
-3,400
| -60% | -$82.6K |
|
5829
nLIGHT
LASR
$3.92B
| $65K | ﹤0.01% |
+4,869
| New | +$54.5K |
|
5830
CALL
908 Devices
MASS
$314M
| $65K | ﹤0.01% |
5,800
-6,200
| -52% | -$42.4K |
|
5831
PUT
Radiant Logistics
RLGT
$386M
| $65K | ﹤0.01% |
9,900
-2,400
| -20% | -$14.5K |
|
5832
CALL
Seacoast Banking Corp of Florida
SBCF
$3.34B
| $65K | ﹤0.01% |
+2,300
| New | +$54.1K |
|
5833
PUT
Trinity Capital Inc.
TRIN
$1.58B
| $65K | ﹤0.01% |
4,500
-6,700
| -60% | -$96.3K |
|
5834
PUT
ZipRecruiter
ZIP
$329M
| $65K | ﹤0.01% |
4,700
-1,700
| -27% | -$21K |
|
|
RCM
5835
PUT
DELISTED
R1 RCM Inc. Common Stock
RCM
| $65K | ﹤0.01% |
6,200
+5,400
| +675% | +$61.2K |
|
|
GRCL
5836
PUT
DELISTED
Gracell Biotechnologies Inc. American Depositary Shares
GRCL
| $65K | ﹤0.01% |
+6,500
| New | +$29.5K |
|
|
WE
5837
PUT
DELISTED
WeWork Inc.
WE
| $65K | ﹤0.01% |
236,000
-12,900
| -5% | -$27.6K |
|
5838
Allogene Therapeutics
ALLO
$659M
| $64K | ﹤0.01% |
+20,210
| New | +$57.3K |
|
5839
PUT
Arcos Dorados Holdings
ARCO
$1.72B
| $64K | ﹤0.01% |
+5,100
| New | +$54.6K |
|
5840
PUT
BioCryst Pharmaceuticals
BCRX
$2.31B
| $64K | ﹤0.01% |
10,800
-32,000
| -75% | -$185K |
|
5841
Cemex
CX
$17B
| $64K | ﹤0.01% |
+8,273
| New | +$56.2K |
|
5842
PUT
Diodes
DIOD
$3.85B
| $64K | ﹤0.01% |
800
+700
| +700% | +$51.1K |
|
5843
Krispy Kreme
DNUT
$560M
| $64K | ﹤0.01% |
+4,265
| New | +$56.4K |
|
5844
PUT
Medallion Financial
MFIN
$233M
| $64K | ﹤0.01% |
6,500
-398,100
| -98% | -$3.31M |
|
5845
CALL
Montauk Renewables
MNTK
$259M
| $64K | ﹤0.01% |
7,200
-200
| -3% | -$1.87K |
|
5846
Protagonist Therapeutics
PTGX
$8.65B
| $64K | ﹤0.01% |
+2,834
| New | +$49.6K |
|
5847
CALL
RxSight
RXST
$247M
| $64K | ﹤0.01% |
1,600
-33,300
| -95% | -$977K |
|
5848
PUT
Scholastic
SCHL
$775M
| $64K | ﹤0.01% |
1,700
-700
| -29% | -$26.8K |
|
|
SKE
5849
Skeena Resources
SKE
$3.26B
| $64K | ﹤0.01% |
13,193
+11,712
| +791% | +$49.4K |
|
5850
PUT
Verrica Pharmaceuticals
VRCA
$90.5M
| $64K | ﹤0.01% |
880
-130
| -13% | -$5.34K |
|
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.