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 | |
|---|---|---|---|---|---|---|
7801
PUT
MasterBrand
MBC
$1.15B
| $2.21K | ﹤0.01% |
+200
| New | +$2.34K |
|
7802
Schwab US Large- Cap ETF
SCHX
$71.3B
| $2.21K | ﹤0.01% |
+82
| New | +$2.19K |
|
|
NOTE
7803
CALL
DELISTED
FiscalNote
NOTE
| $2.21K | ﹤0.01% |
1,500
-32,000
| -96% | -$97.3K |
|
7804
PUT
Jasper Therapeutics
JSPR
$21.1M
| $2.2K | ﹤0.01% |
+1,200
| New | +$2.41K |
|
|
CBLL
7805
CALL
CeriBell Inc
CBLL
$677M
| $2.19K | ﹤0.01% |
+100
| New | +$1.55K |
|
|
BANX
7806
CALL
ArrowMark Financial
BANX
$194M
| $2.18K | ﹤0.01% |
100
-1,200
| -92% | -$26K |
|
7807
PUT
FTC Solar
FTCI
$43.2M
| $2.18K | ﹤0.01% |
200
-300
| -60% | -$2.74K |
|
7808
PUT
Genelux
GNLX
$131M
| $2.18K | ﹤0.01% |
+500
| New | +$2.7K |
|
|
SUIG
7809
PUT
Sui Group Holdings
SUIG
$73M
| $2.17K | ﹤0.01% |
1,300
-2,100
| -62% | -$5.43K |
|
7810
CALL
SurgePays
SURG
$6.03M
| $2.17K | ﹤0.01% |
1,300
-900
| -41% | -$2K |
|
7811
CALL
PCB Bancorp
PCB
$396M
| $2.17K | ﹤0.01% |
+100
| New | +$2.16K |
|
|
PVL
7812
CALL
Permianville Royalty Trust
PVL
$55.8M
| $2.16K | ﹤0.01% |
1,200
| – | – |
|
7813
PUT
CEVA Inc
CEVA
$883M
| $2.15K | ﹤0.01% |
+100
| New | +$2.46K |
|
7814
PUT
AerSale
ASLE
$307M
| $2.13K | ﹤0.01% |
300
-3,900
| -93% | -$27.4K |
|
7815
CALL
ADC Therapeutics
ADCT
$141M
| $2.12K | ﹤0.01% |
600
+300
| +100% | +$1.22K |
|
|
EARN
7816
PUT
Ellington Residential Mortgage REIT
EARN
$167M
| $2.11K | ﹤0.01% |
+400
| New | +$2.1K |
|
7817
PUT
VirTra
VTSI
$33.9M
| $2.1K | ﹤0.01% |
500
-8,500
| -94% | -$44.4K |
|
7818
PUT
America Movil
AMX
$77.2B
| $2.07K | ﹤0.01% |
100
-1,600
| -94% | -$35.2K |
|
7819
CALL
Gladstone Capital
GLAD
$436M
| $2.07K | ﹤0.01% |
100
-500
| -83% | -$10.1K |
|
7820
PUT
Neurogene
NGNE
$663M
| $2.06K | ﹤0.01% |
100
-4,200
| -98% | -$105K |
|
7821
CALL
Inseego
INSG
$111M
| $2.05K | ﹤0.01% |
200
-4,600
| -96% | -$59.7K |
|
7822
CALL
Cenntro
CENN
$8.51M
| $2.05K | ﹤0.01% |
+252
| New | +$3.23K |
|
7823
CALL
SK Telecom
SKM
$11.8B
| $2.05K | ﹤0.01% |
100
-300
| -75% | -$6.16K |
|
7824
PUT
Traeger
COOK
$164M
| $2.05K | ﹤0.01% |
+38
| New | +$1.85K |
|
|
BABO
7825
YieldMax BABA Option Income Strategy ETF
BABO
$17.6M
| $2.05K | ﹤0.01% |
+155
| New | +$2.35K |
|
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.