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 | |
|---|---|---|---|---|---|---|
976
Coherent
COHR
$61.3B
| $8.16M | ﹤0.01% |
44,211
+26,213
| +146% | +$3.92M |
|
977
CALL
Autodesk
ADSK
$43.3B
| $8.14M | ﹤0.01% |
27,500
-3,200
| -10% | -$968K |
|
978
PUT
Corcept Therapeutics
CORT
$10.4B
| $8.13M | ﹤0.01% |
233,700
+213,400
| +1,051% | +$16.8M |
|
979
Spotify
SPOT
$96.4B
| $8.12M | ﹤0.01% |
13,980
+7,744
| +124% | +$4.84M |
|
980
CALL
PNC Financial Services
PNC
$99.5B
| $8.1M | ﹤0.01% |
38,800
+9,900
| +34% | +$1.91M |
|
981
PUT
Kinder Morgan
KMI
$72.9B
| $8.07M | ﹤0.01% |
293,700
-244,900
| -45% | -$6.62M |
|
982
PUT
Tenet Healthcare
THC
$17.1B
| $8.07M | ﹤0.01% |
40,600
-25,800
| -39% | -$5.21M |
|
983
PUT
MetLife
MET
$59.5B
| $8.07M | ﹤0.01% |
102,200
-29,500
| -22% | -$2.33M |
|
984
PUT
Quanta Services
PWR
$98.1B
| $8.06M | ﹤0.01% |
19,100
+3,900
| +26% | +$1.71M |
|
985
PUT
CME Group
CME
$91.9B
| $8.06M | ﹤0.01% |
29,500
-20,500
| -41% | -$5.57M |
|
986
Chipotle Mexican Grill
CMG
$41.1B
| $8.05M | ﹤0.01% |
217,671
-11,775
| -5% | -$426K |
|
987
Starbucks
SBUX
$118B
| $8.03M | ﹤0.01% |
95,334
+29,070
| +44% | +$2.45M |
|
988
CALL
Vanguard Dividend Appreciation ETF
VIG
$110B
| $8.02M | ﹤0.01% |
36,500
-11,900
| -25% | -$2.6M |
|
989
CALL
Tyson Foods
TSN
$20B
| $8.01M | ﹤0.01% |
136,700
+19,200
| +16% | +$1.05M |
|
990
CALL
Cigna
CI
$75.7B
| $8.01M | ﹤0.01% |
29,100
-8,800
| -23% | -$2.47M |
|
991
PUT
Simon Property Group
SPG
$73B
| $7.98M | ﹤0.01% |
43,100
+2,000
| +5% | +$363K |
|
992
CALL
Blue Owl Capital
OWL
$6.22B
| $7.97M | ﹤0.01% |
533,400
-253,200
| -32% | -$3.96M |
|
993
PUT
Symbotic
SYM
$5.16B
| $7.96M | ﹤0.01% |
133,800
-36,400
| -21% | -$2.4M |
|
994
CALL
Toll Brothers
TOL
$13.7B
| $7.95M | ﹤0.01% |
58,800
-1,300
| -2% | -$176K |
|
995
CALL
Aflac
AFL
$63.3B
| $7.95M | ﹤0.01% |
72,100
-43,900
| -38% | -$4.84M |
|
996
CALL
Rubrik
RBRK
$14.9B
| $7.95M | ﹤0.01% |
103,900
-77,500
| -43% | -$5.95M |
|
997
CALL
Akamai
AKAM
$17.1B
| $7.94M | ﹤0.01% |
91,000
+26,100
| +40% | +$2.15M |
|
998
PUT
Emerson Electric
EMR
$81.2B
| $7.92M | ﹤0.01% |
59,700
+35,600
| +148% | +$4.72M |
|
999
CALL
Canadian Solar
CSIQ
$997M
| $7.92M | ﹤0.01% |
333,200
-1,800
| -0.5% | -$39.2K |
|
1000
CALL
SiriusXM
SIRI
$10.1B
| $7.92M | ﹤0.01% |
579,700
-182,800
| -24% | -$3.93M |
|
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.