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 | |
|---|---|---|---|---|---|---|
3651
PUT
Dolby
DLB
$4.85B
| $525K | ﹤0.01% |
6,100
+2,400
| +65% | +$202K |
|
3652
PUT
MKS Inc
MKSI
$21.3B
| $524K | ﹤0.01% |
5,100
+300
| +6% | +$24.4K |
|
3653
CALL
Seadrill
SDRL
$2.69B
| $524K | ﹤0.01% |
11,100
+11,000
| +11,000% | +$466K |
|
3654
PUT
iShares Gold Trust
IAU
$63.4B
| $523K | ﹤0.01% |
13,400
-6,500
| -33% | -$243K |
|
3655
PUT
Outset Medical
OM
$80.1M
| $523K | ﹤0.01% |
+6,447
| New | +$525K |
|
3656
PUT
Energizer
ENR
$1.44B
| $522K | ﹤0.01% |
16,500
+6,300
| +62% | +$200K |
|
3657
PUT
Recursion Pharmaceuticals
RXRX
$1.6B
| $522K | ﹤0.01% |
53,000
-93,900
| -64% | -$670K |
|
3658
PUT
TransUnion
TRU
$14.9B
| $522K | ﹤0.01% |
7,600
-19,200
| -72% | -$1.17M |
|
3659
PUT
Herc Holdings
HRI
$5.34B
| $521K | ﹤0.01% |
3,500
+1,400
| +67% | +$171K |
|
3660
PUT
United Bankshares
UBSI
$6.57B
| $521K | ﹤0.01% |
13,900
+6,100
| +78% | +$194K |
|
3661
CALL
SurgePays
SURG
$6.08M
| $520K | ﹤0.01% |
80,700
-14,300
| -15% | -$76.1K |
|
3662
Chefs' Warehouse
CHEF
$3.9B
| $517K | ﹤0.01% |
+17,590
| New | +$425K |
|
3663
CALL
Lightspeed Commerce
LSPD
$1.35B
| $516K | ﹤0.01% |
24,600
-68,000
| -73% | -$1.08M |
|
3664
PUT
AerSale
ASLE
$307M
| $515K | ﹤0.01% |
40,600
+21,200
| +109% | +$308K |
|
3665
Saic
SAIC
$5.01B
| $515K | ﹤0.01% |
4,148
+2,496
| +151% | +$290K |
|
3666
PUT
Sunoco
SUN
$14B
| $515K | ﹤0.01% |
8,600
+8,100
| +1,620% | +$431K |
|
3667
CALL
Lumen
LUMN
$6.45B
| $514K | ﹤0.01% |
280,900
-234,400
| -45% | -$332K |
|
3668
CALL
RadNet
RDNT
$4.84B
| $514K | ﹤0.01% |
14,800
+13,500
| +1,038% | +$426K |
|
3669
PUT
Virtu Financial
VIRT
$5.12B
| $514K | ﹤0.01% |
25,400
-2,700
| -10% | -$49.8K |
|
|
EU
3670
CALL
enCore Energy
EU
$231M
| $513K | ﹤0.01% |
130,700
+129,600
| +11,782% | +$461K |
|
3671
CALL
Modine Manufacturing
MOD
$12.2B
| $513K | ﹤0.01% |
8,600
-32,300
| -79% | -$1.58M |
|
3672
CALL
Privia Health
PRVA
$3.11B
| $513K | ﹤0.01% |
22,300
-500
| -2% | -$11.2K |
|
|
CVSA
3673
CALL
Covista Inc
CVSA
$4.09B
| $512K | ﹤0.01% |
8,700
+3,200
| +58% | +$171K |
|
|
ODP
3674
CALL
DELISTED
ODP
ODP
| $512K | ﹤0.01% |
9,100
+2,400
| +36% | +$114K |
|
3675
CALL
Brown & Brown
BRO
$23.6B
| $511K | ﹤0.01% |
7,200
-28,400
| -80% | -$2.03M |
|
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.