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 | |
|---|---|---|---|---|---|---|
5051
CALL
MicroSectors FANG+ ETNs due Jan 8 2038
FNGS
$556M
| $95.3K | ﹤0.01% |
1,400
+200
| +17% | +$14.1K |
|
5052
PUT
Choice Hotels
CHH
$5.07B
| $95.3K | ﹤0.01% |
1,000
-1,300
| -57% | -$124K |
|
5053
CALL
Capital Southwest
CSWC
$1.47B
| $95.2K | ﹤0.01% |
4,300
-6,600
| -61% | -$139K |
|
5054
PUT
AMC Global Media
AMCX
$492M
| $95.2K | ﹤0.01% |
10,000
-35,000
| -78% | -$295K |
|
5055
PUT
Twist Bioscience
TWST
$5.7B
| $95.2K | ﹤0.01% |
3,000
-9,200
| -75% | -$287K |
|
5056
CALL
FingerMotion
FNGR
$16.6M
| $95.1K | ﹤0.01% |
77,300
-41,500
| -35% | -$61.6K |
|
5057
CALL
Douglas Elliman
DOUG
$154M
| $95K | ﹤0.01% |
40,100
-300
| -0.7% | -$772 |
|
5058
PUT
Columbia Banking Systems
COLB
$8.84B
| $95K | ﹤0.01% |
3,400
-700
| -17% | -$18.9K |
|
5059
Children's Place
PLCE
$54.3M
| $94.9K | ﹤0.01% |
+23,846
| New | +$171K |
|
5060
CALL
Cirrus Logic
CRUS
$6.53B
| $94.8K | ﹤0.01% |
800
-600
| -43% | -$73.9K |
|
|
BTQ
5061
PUT
BTQ Technologies Corp
BTQ
$500M
| $94.7K | ﹤0.01% |
+18,500
| New | +$140K |
|
5062
CALL
Palladyne AI
PDYN
$247M
| $94.6K | ﹤0.01% |
22,200
-40,000
| -64% | -$269K |
|
5063
CALL
Allot
ALLT
$372M
| $94.4K | ﹤0.01% |
9,600
-27,100
| -74% | -$260K |
|
|
PRA
5064
PUT
DELISTED
ProAssurance
PRA
| $94.2K | ﹤0.01% |
3,900
-200
| -5% | -$4.81K |
|
5065
PUT
Integer Holdings
ITGR
$4.12B
| $94.1K | ﹤0.01% |
+1,200
| New | +$95.6K |
|
5066
PUT
Clearwater Paper
CLW
$339M
| $94K | ﹤0.01% |
5,400
-3,300
| -38% | -$60.8K |
|
5067
PUT
NCR Voyix
VYX
$1.14B
| $93.8K | ﹤0.01% |
9,200
-141,200
| -94% | -$1.53M |
|
|
UROY
5068
PUT
Uranium Royalty Corp
UROY
$1.3B
| $93.8K | ﹤0.01% |
26,500
+7,500
| +39% | +$29.3K |
|
5069
PUT
Goldman Sachs Physical Gold ETF Shares
AAAU
$2.46B
| $93.6K | ﹤0.01% |
2,200
+2,000
| +1,000% | +$82K |
|
5070
CALL
CNO Financial Group
CNO
$5.14B
| $93.4K | ﹤0.01% |
2,200
+2,000
| +1,000% | +$81.5K |
|
5071
CALL
Centuri Holdings
CTRI
$2.81B
| $93.4K | ﹤0.01% |
3,700
+3,100
| +517% | +$69.3K |
|
5072
PUT
Penumbra
PEN
$12.6B
| $93.3K | ﹤0.01% |
300
+100
| +50% | +$27.6K |
|
5073
PUT
AppFolio
APPF
$6.38B
| $93.1K | ﹤0.01% |
400
+300
| +300% | +$71.3K |
|
|
IAUI
5074
NEOS Gold High Income ETF
IAUI
$490M
| $92.9K | ﹤0.01% |
1,663
+1,117
| +205% | +$61.2K |
|
5075
Invesco Galaxy Bitcoin ETF
BTCO
$422M
| $92.7K | ﹤0.01% |
+1,064
| New | +$106K |
|
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.