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 | |
|---|---|---|---|---|---|---|
3576
Alliance Resource Partners
ARLP
$3.3B
| $558K | ﹤0.01% |
+26,358
| New | +$571K |
|
3577
iShares US Treasury Bond ETF
GOVT
$43.8B
| $558K | ﹤0.01% |
24,219
+23,697
| +4,540% | +$527K |
|
3578
PUT
Shattuck Labs
STTK
$672M
| $558K | ﹤0.01% |
+78,300
| New | +$214K |
|
|
SWTX
3579
CALL
DELISTED
SpringWorks Therapeutics
SWTX
| $558K | ﹤0.01% |
15,300
+14,200
| +1,291% | +$371K |
|
3580
CALL
American Coastal Insurance
ACIC
$505M
| $556K | ﹤0.01% |
58,800
-67,400
| -53% | -$542K |
|
3581
PUT
Alta Equipment Group
ALTG
$208M
| $555K | ﹤0.01% |
44,900
+8,300
| +23% | +$89.6K |
|
3582
CALL
Ardmore Shipping
ASC
$669M
| $555K | ﹤0.01% |
39,400
-1,200
| -3% | -$16.2K |
|
3583
Flywire
FLYW
$1.99B
| $555K | ﹤0.01% |
23,995
-4,258
| -15% | -$107K |
|
|
CTLT
3584
DELISTED
CATALENT, INC.
CTLT
| $555K | ﹤0.01% |
+12,369
| New | +$500K |
|
3585
CALL
Alcon
ALC
$32.8B
| $554K | ﹤0.01% |
7,100
-18,900
| -73% | -$1.4M |
|
|
KEEL
3586
Keel Infrastructure Corp
KEEL
$2.45B
| $554K | ﹤0.01% |
190,663
+152,926
| +405% | +$246K |
|
|
CNR
3587
Core Natural Resources Inc
CNR
$4.16B
| $554K | ﹤0.01% |
+5,516
| New | +$561K |
|
|
MAG
3588
CALL
DELISTED
MAG Silver
MAG
| $553K | ﹤0.01% |
53,200
-16,900
| -24% | -$181K |
|
3589
Designer Brands
DBI
$298M
| $552K | ﹤0.01% |
62,440
+11,740
| +23% | +$124K |
|
3590
CALL
ProShares UltraShort Industrials
SIJ
$5.69M
| $552K | ﹤0.01% |
4,275
+3,500
| +452% | +$191K |
|
3591
PUT
Aramark
ARMK
$15.2B
| $550K | ﹤0.01% |
61,000
-17,945
| -23% | -$486K |
|
3592
PUT
Boyd Gaming
BYD
$6.64B
| $550K | ﹤0.01% |
8,800
-2,300
| -21% | -$136K |
|
3593
CALL
Moelis & Co
MC
$5.04B
| $550K | ﹤0.01% |
9,800
-4,500
| -31% | -$211K |
|
3594
Sprouts Farmers Market
SFM
$7.23B
| $550K | ﹤0.01% |
11,436
+168
| +1% | +$7.35K |
|
3595
Seagate
STX
$185B
| $550K | ﹤0.01% |
+6,445
| New | +$481K |
|
3596
Inspire Medical Systems
INSP
$1.47B
| $549K | ﹤0.01% |
+2,699
| New | +$437K |
|
3597
PUT
Sally Beauty Holdings
SBH
$1.43B
| $549K | ﹤0.01% |
41,400
+40,300
| +3,664% | +$390K |
|
3598
CALL
Sibanye-Stillwater
SBSW
$6.05B
| $548K | ﹤0.01% |
101,000
+75,200
| +291% | +$389K |
|
3599
CALL
Artisan Partners
APAM
$2.86B
| $547K | ﹤0.01% |
12,400
-21,200
| -63% | -$800K |
|
3600
PUT
Customers Bancorp
CUBI
$2.66B
| $547K | ﹤0.01% |
9,500
+5,000
| +111% | +$217K |
|
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.