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 | |
|---|---|---|---|---|---|---|
4901
CALL
Krispy Kreme
DNUT
$553M
| $159K | ﹤0.01% |
10,600
-4,000
| -27% | -$52.9K |
|
4902
PUT
Humacyte
HUMA
$181M
| $159K | ﹤0.01% |
56,200
+49,200
| +703% | +$126K |
|
|
IAS
4903
DELISTED
Integral Ad Science
IAS
| $159K | ﹤0.01% |
11,070
+2,542
| +30% | +$34K |
|
4904
CALL
Alliant Energy
LNT
$18.3B
| $159K | ﹤0.01% |
3,100
-6,100
| -66% | -$304K |
|
4905
Medpace
MEDP
$16.1B
| $159K | ﹤0.01% |
+520
| New | +$140K |
|
4906
MACOM Technology Solutions
MTSI
$19B
| $159K | ﹤0.01% |
1,712
-2,712
| -61% | -$223K |
|
|
RVPH
4907
PUT
DELISTED
REVIVA PHARMA HLDGS INC
RVPH
| $159K | ﹤0.01% |
1,550
-30
| -2% | -$2.69K |
|
4908
PUT
Spire Global
SPIR
$440M
| $159K | ﹤0.01% |
20,400
-5,000
| -20% | -$25.6K |
|
4909
Mammoth Energy Services
TUSK
$125M
| $159K | ﹤0.01% |
35,792
+29,296
| +451% | +$130K |
|
4910
US Commodity Index
USCI
$369M
| $159K | ﹤0.01% |
2,828
+1,093
| +63% | +$63.3K |
|
|
SLCA
4911
DELISTED
U.S. SILICA HOLDINGS, INC.
SLCA
| $159K | ﹤0.01% |
14,103
+321
| +2% | +$3.8K |
|
4912
CALL
BlueLinx
BXC
$416M
| $158K | ﹤0.01% |
1,400
+800
| +133% | +$69.4K |
|
4913
CALL
Corporacion America
CAAP
$4.26B
| $158K | ﹤0.01% |
9,900
+9,300
| +1,550% | +$123K |
|
4914
CALL
8x8 Inc
EGHT
$262M
| $158K | ﹤0.01% |
42,000
-2,800
| -6% | -$8.31K |
|
4915
LSB Industries
LXU
$794M
| $158K | ﹤0.01% |
+17,070
| New | +$156K |
|
4916
PUT
NGL Energy Partners
NGL
$2.01B
| $158K | ﹤0.01% |
28,400
-7,800
| -22% | -$33.8K |
|
4917
PUT
SiTime
SITM
$15.8B
| $158K | ﹤0.01% |
1,300
+500
| +63% | +$56.6K |
|
4918
CALL
Alkermes
ALKS
$8.39B
| $157K | ﹤0.01% |
46,700
+5,800
| +14% | +$151K |
|
4919
WisdomTree Emerging Markets High Dividend Fund
DEM
$3.9B
| $157K | ﹤0.01% |
+3,872
| New | +$148K |
|
4920
DTE Energy
DTE
$29.5B
| $157K | ﹤0.01% |
1,429
-13,813
| -91% | -$1.42M |
|
|
SFIX
4921
Stitch Fix
SFIX
$547M
| $157K | ﹤0.01% |
44,107
-24,470
| -36% | -$86.3K |
|
|
ATSG
4922
DELISTED
Air Transport Services Group
ATSG
| $157K | ﹤0.01% |
8,958
+4,950
| +124% | +$88K |
|
4923
Core Laboratories
CLB
$477M
| $156K | ﹤0.01% |
8,834
+3,221
| +57% | +$64.9K |
|
4924
PUT
Carlisle Companies
CSL
$15B
| $156K | ﹤0.01% |
500
-1,200
| -71% | -$330K |
|
4925
PUT
Denison Mines
DNN
$2.64B
| $156K | ﹤0.01% |
88,700
-10,400
| -10% | -$17.4K |
|
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.