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 | |
|---|---|---|---|---|---|---|
1026
CALL
GSK
GSK
$102B
| $7.61M | ﹤0.01% |
155,200
-88,600
| -36% | -$4.13M |
|
1027
PUT
S&P Global
SPGI
$124B
| $7.58M | ﹤0.01% |
14,500
-7,300
| -33% | -$3.61M |
|
1028
CALL
Copart
CPRT
$25.2B
| $7.58M | ﹤0.01% |
193,500
| – | – |
|
1029
CALL
Plains GP Holdings
PAGP
$5.25B
| $7.55M | ﹤0.01% |
394,300
+147,600
| +60% | +$2.66M |
|
1030
CALL
Progressive
PGR
$120B
| $7.54M | ﹤0.01% |
33,100
-1,100
| -3% | -$248K |
|
1031
Cloudflare
NET
$93.1B
| $7.49M | ﹤0.01% |
37,976
+13,720
| +57% | +$2.9M |
|
1032
CALL
AGNC Investment
AGNC
$12.3B
| $7.47M | ﹤0.01% |
696,600
-334,200
| -32% | -$3.44M |
|
1033
PUT
abrdn Physical Palladium Shares ETF
PALL
$609M
| $7.46M | ﹤0.01% |
256,500
+186,000
| +264% | +$5.01M |
|
|
DENT
1034
PUT
DELISTED
AdvisorShares Dent Tactical ETF
DENT
| $7.45M | ﹤0.01% |
1,574,200
+697,100
| +79% | +$3.3M |
|
1035
PUT
CRISPR Therapeutics
CRSP
$4.68B
| $7.41M | ﹤0.01% |
141,300
-12,600
| -8% | -$755K |
|
1036
PUT
Rubrik
RBRK
$14.9B
| $7.39M | ﹤0.01% |
96,600
-46,500
| -32% | -$3.57M |
|
1037
CALL
FirstEnergy
FE
$28.6B
| $7.38M | ﹤0.01% |
164,900
+78,900
| +92% | +$3.62M |
|
1038
PUT
Waste Management
WM
$95.3B
| $7.36M | ﹤0.01% |
33,500
-9,600
| -22% | -$2.05M |
|
1039
TJX Companies
TJX
$170B
| $7.34M | ﹤0.01% |
+47,815
| New | +$7.07M |
|
1040
CALL
Colgate-Palmolive
CL
$72.1B
| $7.33M | ﹤0.01% |
92,700
-17,400
| -16% | -$1.36M |
|
1041
State Street Technology Select Sector SPDR ETF
XLK
$116B
| $7.3M | ﹤0.01% |
50,713
-102,953
| -67% | -$14.9M |
|
1042
CALL
LyondellBasell Industries
LYB
$19.9B
| $7.26M | ﹤0.01% |
167,700
+9,400
| +6% | +$426K |
|
1043
Xtrackers Harvest CSI 300 China A-Shares ETF
ASHR
$1.37B
| $7.26M | ﹤0.01% |
220,929
+218,375
| +8,550% | +$7.16M |
|
1044
Iris Energy
IREN
$14.5B
| $7.25M | ﹤0.01% |
191,894
-1,250,705
| -87% | -$64.5M |
|
|
GAP
1045
PUT
The Gap Inc
GAP
$6.8B
| $7.24M | ﹤0.01% |
282,700
-196,700
| -41% | -$4.77M |
|
1046
PUT
CSX Corp
CSX
$97.8B
| $7.22M | ﹤0.01% |
199,200
-575,900
| -74% | -$20.6M |
|
|
JBS
1047
PUT
JBS N.V.
JBS
$39.9B
| $7.22M | ﹤0.01% |
500,500
-18,500
| -4% | -$254K |
|
1048
CALL
SSR Mining
SSRM
$5.64B
| $7.21M | ﹤0.01% |
329,000
-87,000
| -21% | -$1.94M |
|
|
FISV
1049
Fiserv Inc
FISV
$26.6B
| $7.2M | ﹤0.01% |
107,216
+99,457
| +1,282% | +$8.33M |
|
|
BNY
1050
PUT
Bank of New York Mellon
BNY
$109B
| $7.14M | ﹤0.01% |
61,500
-62,500
| -50% | -$6.92M |
|
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.