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 | |
|---|---|---|---|---|---|---|
6026
PUT
Lithia Motors
LAD
$8.47B
| $33.2K | ﹤0.01% |
100
-1,600
| -94% | -$508K |
|
6027
CALL
Cabot Corp
CBT
$4.54B
| $33.1K | ﹤0.01% |
500
-100
| -17% | -$6.66K |
|
6028
CALL
SunCoke Energy
SXC
$720M
| $33.1K | ﹤0.01% |
4,600
-1,600
| -26% | -$11.8K |
|
6029
CALL
Barnes & Noble Education
BNED
$431M
| $33.1K | ﹤0.01% |
3,600
-84,500
| -96% | -$745K |
|
6030
CALL
Peoples Bancorp
PEBO
$1.5B
| $33K | ﹤0.01% |
1,100
+600
| +120% | +$17.8K |
|
|
MNRS
6031
PUT
Grayscale Bitcoin Miners ETF
MNRS
$12.1M
| $33K | ﹤0.01% |
1,100
+500
| +83% | +$20.1K |
|
|
ZEPP
6032
Zepp Health
ZEPP
$66.4M
| $32.9K | ﹤0.01% |
+1,221
| New | +$43.5K |
|
6033
DMC Global
BOOM
$138M
| $32.9K | ﹤0.01% |
4,913
+2,742
| +126% | +$18.9K |
|
6034
Five Point Holdings
FPH
$373M
| $32.9K | ﹤0.01% |
5,879
-2,037
| -26% | -$12K |
|
|
NOTE
6035
PUT
DELISTED
FiscalNote
NOTE
| $32.8K | ﹤0.01% |
22,300
-30,700
| -58% | -$93.3K |
|
6036
PUT
V2X
VVX
$2.83B
| $32.7K | ﹤0.01% |
600
+300
| +100% | +$16.9K |
|
|
ARX
6037
CALL
Accelerant Holdings
ARX
$2.59B
| $32.7K | ﹤0.01% |
2,000
-1,700
| -46% | -$23.9K |
|
6038
PUT
Cincinnati Financial
CINF
$27.3B
| $32.7K | ﹤0.01% |
200
+100
| +100% | +$16.2K |
|
6039
PUT
Amylyx Pharmaceuticals
AMLX
$2.26B
| $32.6K | ﹤0.01% |
2,700
-6,900
| -72% | -$93.7K |
|
6040
CALL
Robert Half
RHI
$3.87B
| $32.6K | ﹤0.01% |
1,200
-4,600
| -79% | -$131K |
|
|
BKV
6041
PUT
BKV Corp
BKV
$2.68B
| $32.6K | ﹤0.01% |
+1,200
| New | +$30.1K |
|
6042
PUT
Construction Partners
ROAD
$5.84B
| $32.6K | ﹤0.01% |
300
+100
| +50% | +$11.3K |
|
|
NMAX
6043
CALL
Newsmax Inc
NMAX
$996M
| $32.5K | ﹤0.01% |
4,200
-30,200
| -88% | -$290K |
|
6044
Pacer US Cash Cows 100 ETF
COWZ
$18.8B
| $32.4K | ﹤0.01% |
539
+232
| +76% | +$13.6K |
|
6045
PUT
HEICO Corp Class A
HEI.A
$36B
| $32.4K | ﹤0.01% |
100
-18,900
| -99% | -$4.67M |
|
6046
PUT
Axalta
AXTA
$7.66B
| $32.3K | ﹤0.01% |
1,000
+500
| +100% | +$14.7K |
|
6047
CALL
Tradeweb Markets
TW
$21.4B
| $32.3K | ﹤0.01% |
300
-2,600
| -90% | -$279K |
|
6048
Otter Tail
OTTR
$3.71B
| $32.2K | ﹤0.01% |
399
+43
| +12% | +$3.48K |
|
6049
QuinStreet
QNST
$890M
| $32.2K | ﹤0.01% |
2,240
-1,128
| -33% | -$16.3K |
|
6050
PUT
Schrodinger
SDGR
$1.13B
| $32.2K | ﹤0.01% |
1,800
-1,500
| -45% | -$28.4K |
|
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.