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 | |
|---|---|---|---|---|---|---|
1701
CALL
Royal Bank of Canada
RY
$291B
| $2.85M | ﹤0.01% |
16,700
-67,000
| -80% | -$10.3M |
|
1702
CALL
Halozyme
HALO
$9.72B
| $2.85M | ﹤0.01% |
42,300
+16,600
| +65% | +$1.12M |
|
1703
CALL
Raymond James Financial
RJF
$32.5B
| $2.84M | ﹤0.01% |
17,700
-2,800
| -14% | -$452K |
|
1704
PUT
PennyMac Financial
PFSI
$4.38B
| $2.83M | ﹤0.01% |
21,500
-11,900
| -36% | -$1.52M |
|
1705
CALL
Aurora
AUR
$11.7B
| $2.83M | ﹤0.01% |
736,800
+100,000
| +16% | +$458K |
|
1706
CALL
Yum! Brands
YUM
$41B
| $2.83M | ﹤0.01% |
18,700
-8,800
| -32% | -$1.3M |
|
1707
AdvisorShares Pure US Cannabis ETF
MSOS
$864M
| $2.81M | ﹤0.01% |
596,105
+174,370
| +41% | +$777K |
|
1708
CALL
Axsome Therapeutics
AXSM
$12.4B
| $2.81M | ﹤0.01% |
15,400
-39,900
| -72% | -$5.57M |
|
1709
PUT
O'Reilly Automotive
ORLY
$72.4B
| $2.81M | ﹤0.01% |
30,800
-26,800
| -47% | -$2.62M |
|
1710
NRG Energy
NRG
$29.8B
| $2.8M | ﹤0.01% |
17,567
-13,289
| -43% | -$2.2M |
|
1711
Carnival Corporation Ltd
CCL
$36.1B
| $2.79M | ﹤0.01% |
+91,445
| New | +$2.55M |
|
1712
CALL
Guardant Health
GH
$19.5B
| $2.79M | ﹤0.01% |
27,300
-56,800
| -68% | -$5.08M |
|
1713
CALL
Equinor
EQNR
$95.9B
| $2.79M | ﹤0.01% |
117,900
-54,300
| -32% | -$1.28M |
|
|
RNAM
1714
DELISTED
Avidity Biosciences
RNAM
| $2.78M | ﹤0.01% |
38,607
-6,291
| -14% | -$406K |
|
1715
PUT
Cytokinetics
CYTK
$11B
| $2.78M | ﹤0.01% |
43,700
-75,600
| -63% | -$4.7M |
|
1716
PUT
Stryker
SYK
$127B
| $2.78M | ﹤0.01% |
7,900
-1,200
| -13% | -$437K |
|
1717
CALL
Rush Street Interactive
RSI
$3.24B
| $2.77M | ﹤0.01% |
142,800
-73,900
| -34% | -$1.37M |
|
1718
CALL
Yeti Holdings
YETI
$3.82B
| $2.77M | ﹤0.01% |
62,800
-6,800
| -10% | -$262K |
|
1719
PUT
Burlington
BURL
$22B
| $2.77M | ﹤0.01% |
9,600
-38,600
| -80% | -$10.5M |
|
1720
PUT
Vodafone
VOD
$34.9B
| $2.77M | ﹤0.01% |
209,900
+79,400
| +61% | +$961K |
|
1721
CALL
Cinemark Holdings
CNK
$3.82B
| $2.77M | ﹤0.01% |
119,300
-82,500
| -41% | -$2.17M |
|
1722
CALL
Fastly Inc
FSLY
$3.17B
| $2.77M | ﹤0.01% |
272,300
-30,000
| -10% | -$296K |
|
1723
Quanta Services
PWR
$93.9B
| $2.76M | ﹤0.01% |
+6,534
| New | +$2.87M |
|
|
SW
1724
CALL
Smurfit Westrock
SW
$25.5B
| $2.75M | ﹤0.01% |
71,200
+19,900
| +39% | +$759K |
|
1725
Warby Parker
WRBY
$3.01B
| $2.75M | ﹤0.01% |
+126,190
| New | +$2.75M |
|
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.