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 |
Netflix
NFLX
|
+$73.1M |
| 2 |
Western Digital
WDC
|
+$51.8M |
| 3 |
iShares Semiconductor ETF
SOXX
|
+$46M |
| 4 |
Meta Platforms (Facebook)
META
|
+$41.8M |
| 5 |
Alibaba
BABA
|
+$37.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
NVIDIA
NVDA
|
+$262M |
| 2 |
Microsoft
MSFT
|
+$194M |
| 3 |
iShares Russell 2000 ETF
IWM
|
+$149M |
| 4 |
Apple
AAPL
|
+$119M |
| 5 |
Amazon
AMZN
|
+$107M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.59% |
| 2 | Consumer Discretionary | 0.21% |
| 3 | Healthcare | 0.2% |
| 4 | Industrials | 0.18% |
| 5 | Communication Services | 0.16% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
2926
PUT
Gold Royalty Corp
GROY
$609M
| $733K | ﹤0.01% |
181,500
+102,600
| +130% | +$393K |
|
2927
PUT
Dine Brands
DIN
$448M
| $733K | ﹤0.01% |
22,800
+1,100
| +5% | +$31.9K |
|
2928
CALL
Olema Pharmaceuticals
OLMA
$1.05B
| $733K | ﹤0.01% |
29,300
-42,900
| -59% | -$763K |
|
2929
Semtech
SMTC
$11.3B
| $732K | ﹤0.01% |
9,936
-2,337
| -19% | -$166K |
|
2930
Trex
TREX
$4.57B
| $731K | ﹤0.01% |
20,847
+16,870
| +424% | +$682K |
|
2931
CALL
Manchester United
MANU
$3.96B
| $729K | ﹤0.01% |
45,800
-69,500
| -60% | -$1.12M |
|
2932
PUT
Global X S&P 500 Tail Risk ETF
XTR
$4.76M
| $727K | ﹤0.01% |
11,300
+6,000
| +113% | +$184K |
|
2933
CALL
Option Care Health
OPCH
$3.42B
| $726K | ﹤0.01% |
22,800
+2,100
| +10% | +$61.6K |
|
|
CMPS
2934
Compass Pathways
CMPS
$1.52B
| $726K | ﹤0.01% |
105,230
-15,658
| -13% | -$95.5K |
|
2935
CALL
SES AI
SES
$205M
| $726K | ﹤0.01% |
403,300
+226,900
| +129% | +$509K |
|
2936
PUT
Flex
FLEX
$42.5B
| $725K | ﹤0.01% |
12,400
-19,900
| -62% | -$1.23M |
|
2937
Xcel Energy
XEL
$50.4B
| $725K | ﹤0.01% |
9,811
-9,248
| -49% | -$729K |
|
2938
CALL
Carpenter Technology
CRS
$28.8B
| $724K | ﹤0.01% |
2,300
-5,300
| -70% | -$1.59M |
|
|
CMBT
2939
CMB.TECH NV
CMBT
$4.46B
| $724K | ﹤0.01% |
74,993
-53,486
| -42% | -$520K |
|
|
LX
2940
CALL
LexinFintech Holdings
LX
$241M
| $724K | ﹤0.01% |
221,300
+74,300
| +51% | +$305K |
|
2941
PUT
Ollie's Bargain Outlet
OLLI
$4.04B
| $723K | ﹤0.01% |
6,600
-2,700
| -29% | -$326K |
|
2942
PUT
Blackstone Secured Lending
BXSL
$5.36B
| $721K | ﹤0.01% |
27,400
-39,200
| -59% | -$1.05M |
|
|
GRNY
2943
FundStrat Granny Shots US Large Cap ETF
GRNY
$4.3B
| $721K | ﹤0.01% |
29,107
-18,079
| -38% | -$454K |
|
2944
CALL
Healthcare Realty
HR
$7.46B
| $720K | ﹤0.01% |
42,500
+41,200
| +3,169% | +$733K |
|
2945
PUT
Children's Place
PLCE
$52.9M
| $720K | ﹤0.01% |
180,800
+158,100
| +696% | +$1.13M |
|
2946
CALL
Bakkt Inc
BKKT
$338M
| $719K | ﹤0.01% |
898,300
-294,200
| -25% | -$6.5M |
|
2947
Rapid7
RPD
$644M
| $719K | ﹤0.01% |
47,291
+4,047
| +9% | +$66.6K |
|
2948
PUT
Casey's General Stores
CASY
$31.6B
| $719K | ﹤0.01% |
1,300
-800
| -38% | -$440K |
|
2949
Charles River Laboratories
CRL
$10.8B
| $718K | ﹤0.01% |
+3,601
| New | +$653K |
|
2950
PUT
Henry Schein
HSIC
$9.64B
| $718K | ﹤0.01% |
9,500
-1,200
| -11% | -$84.4K |
|
Similar funds
Simplex Trading's Q4 2025 Portfolio in Review
As of Q4 2025, Simplex Trading held 10,526 positions worth $177B, down 9% from $195B the previous quarter. Its ten largest holdings account for 49% of the portfolio.
Simplex Trading withdrew a net $23.2B in Q4 2025, closing 2,184 positions and reducing 4,088 holdings. Its most notable exit was iShares Russell 2000 ETF, an estimated $149M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.59% of assets, down from 0.79% a quarter earlier, followed by Consumer Discretionary and Healthcare.
Against the trend, Simplex Trading opened a new position in Western Digital worth $58.9M.
- Simplex Trading's largest Q4 2025 buy was Western Digital: 341,762 shares worth $58.9M.
- Simplex Trading added most to Netflix in Q4 2025, an estimated $73.1M increase.
- Simplex Trading's biggest Q4 2025 reduction was NVIDIA, cutting an estimated $262M.
- Simplex Trading fully exited iShares Russell 2000 ETF in Q4 2025, selling an estimated $149M.
- Simplex Trading's ten largest holdings make up 49% of its $177B portfolio in Q4 2025.
- Simplex Trading opened 1,476 new positions and closed 2,184 in Q4 2025.
- Simplex Trading's portfolio value fell 9% quarter-over-quarter to $177B.
Based on Simplex Trading's 13F filing for Q4 2025, filed 11 Feb 2026.