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 | |
|---|---|---|---|---|---|---|
6526
PUT
GSI Technology
GSIT
$206M
| $31K | ﹤0.01% |
12,000
-23,600
| -66% | -$59.3K |
|
6527
CALL
Healthcare Services Group
HCSG
$1.6B
| $31K | ﹤0.01% |
3,000
| – | – |
|
6528
CALL
Hyliion Holdings
HYLN
$594M
| $31K | ﹤0.01% |
38,600
-22,400
| -37% | -$15.9K |
|
6529
CALL
Innovative Solutions & Support
ISSC
$318M
| $31K | ﹤0.01% |
3,700
-800
| -18% | -$6.08K |
|
6530
PUT
MDU Resources
MDU
$4.28B
| $31K | ﹤0.01% |
2,888
-181
| -6% | -$1.91K |
|
6531
CALL
Manitowoc
MTW
$501M
| $31K | ﹤0.01% |
1,900
-14,000
| -88% | -$204K |
|
6532
CALL
N-able
NABL
$835M
| $31K | ﹤0.01% |
2,400
+2,200
| +1,100% | +$27.9K |
|
6533
PUT
Oceaneering
OII
$4.71B
| $31K | ﹤0.01% |
1,500
-1,900
| -56% | -$42.1K |
|
6534
CALL
Puma Biotechnology
PBYI
$399M
| $31K | ﹤0.01% |
7,200
+5,000
| +227% | +$16.6K |
|
6535
CALL
Precigen
PGEN
$1.92B
| $31K | ﹤0.01% |
23,700
| – | – |
|
6536
Praxis Precision Medicines
PRAX
$8.14B
| $31K | ﹤0.01% |
+1,392
| New | +$25.1K |
|
6537
SiTime
SITM
$14B
| $31K | ﹤0.01% |
255
+205
| +410% | +$23.2K |
|
|
SOHU
6538
Sohu.com
SOHU
$348M
| $31K | ﹤0.01% |
3,160
-3,345
| -51% | -$29.9K |
|
6539
PUT
Spire
SR
$4.91B
| $31K | ﹤0.01% |
500
+100
| +25% | +$5.97K |
|
|
TGB
6540
CALL
Trekor Metals
TGB
$2.45B
| $31K | ﹤0.01% |
22,800
-400
| -2% | -$491 |
|
6541
ProShares VIX Mid-Term Futures ETF
VIXM
$56.4M
| $31K | ﹤0.01% |
1,861
-5,417
| -74% | -$100K |
|
6542
Vanda Pharmaceuticals
VNDA
$303M
| $31K | ﹤0.01% |
7,405
+6,124
| +478% | +$24.7K |
|
6543
CALL
Vestis
VSTS
$2.05B
| $31K | ﹤0.01% |
+1,500
| New | +$25.7K |
|
6544
PUT
Weis Markets
WMK
$1.93B
| $31K | ﹤0.01% |
500
+400
| +400% | +$25.5K |
|
|
WSR
6545
PUT
DELISTED
Whitestone REIT
WSR
| $31K | ﹤0.01% |
2,600
+1,300
| +100% | +$13.9K |
|
|
RPT
6546
Rithm Property Trust
RPT
$95.4M
| $31K | ﹤0.01% |
991
+420
| +74% | +$12.9K |
|
|
EGRX
6547
PUT
DELISTED
Eagle Pharmaceuticals, Inc.
EGRX
| $31K | ﹤0.01% |
+6,000
| New | +$59.2K |
|
|
NS
6548
PUT
DELISTED
NuStar Energy L.P.
NS
| $31K | ﹤0.01% |
1,700
-500
| -23% | -$8.93K |
|
|
THRX
6549
PUT
DELISTED
Theseus Pharmaceuticals, Inc. Common Stock
THRX
| $31K | ﹤0.01% |
+7,900
| New | +$24.1K |
|
6550
PUT
Aldeyra Therapeutics
ALDX
$93.5M
| $30K | ﹤0.01% |
8,600
-23,100
| -73% | -$71.3K |
|
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.