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 | Miscellaneous | 98.27% |
| 2 | Technology | 0.59% |
| 3 | Consumer Discretionary | 0.21% |
| 4 | Healthcare | 0.2% |
| 5 | Industrials | 0.18% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
551
CALL
British American Tobacco
BTI
$119B
| $19.7M | 0.01% |
348,200
-388,100
| -53% | -$21.2M |
|
552
CALL
Altria Group
MO
$115B
| $19.7M | 0.01% |
341,400
-71,100
| -17% | -$4.29M |
|
553
CALL
Lowe's Companies
LOW
$115B
| $19.7M | 0.01% |
81,600
-50,000
| -38% | -$12M |
|
554
Newmont
NEM
$135B
| $19.7M | 0.01% |
+197,022
| New | +$17.8M |
|
|
SHNY
555
CALL
DELISTED
Direxion Daily Silver Miners Index Bull 2X Shares
SHNY
| $19.7M | 0.01% |
766,100
-234,100
| -23% | -$6.01M |
|
556
PUT
Abercrombie & Fitch
ANF
$6.65B
| $19.6M | 0.01% |
155,900
+20,600
| +15% | +$1.8M |
|
557
CALL
SentinelOne
S
$6.92B
| $19.6M | 0.01% |
1,305,200
+435,400
| +50% | +$7.13M |
|
558
PUT
Snap
SNAP
$9.25B
| $19.5M | 0.01% |
2,417,700
-616,400
| -20% | -$4.88M |
|
559
CALL
Medtronic
MDT
$120B
| $19.5M | 0.01% |
203,000
-91,900
| -31% | -$8.93M |
|
560
CALL
First Horizon
FHN
$11.8B
| $19.5M | 0.01% |
813,900
+733,400
| +911% | +$16.3M |
|
561
PUT
Dollar Tree
DLTR
$24.7B
| $19.4M | 0.01% |
158,000
-30,500
| -16% | -$3.27M |
|
562
PUT
Gilead Sciences
GILD
$187B
| $19.4M | 0.01% |
158,100
-58,100
| -27% | -$7.06M |
|
563
CALL
Twilio
TWLO
$35.8B
| $19.4M | 0.01% |
136,200
-43,200
| -24% | -$5.35M |
|
564
CALL
Sunrun
RUN
$2.14B
| $19.3M | 0.01% |
1,051,500
+86,300
| +9% | +$1.65M |
|
565
CALL
Proshares UltraShort Technology
REW
$3M
| $19.3M | 0.01% |
625,050
-488,675
| -44% | -$10.9M |
|
566
CALL
Mercado Libre
MELI
$100B
| $19.1M | 0.01% |
9,500
-1,000
| -10% | -$2.1M |
|
567
Boeing
BA
$168B
| $19M | 0.01% |
+87,723
| New | +$18M |
|
568
CALL
EQT Corp
EQT
$34.5B
| $18.9M | 0.01% |
352,900
-229,500
| -39% | -$12.9M |
|
569
PUT
Okta
OKTA
$29.8B
| $18.9M | 0.01% |
218,600
-36,500
| -14% | -$3.19M |
|
570
CALL
UiPath
PATH
$7.87B
| $18.8M | 0.01% |
1,150,000
+212,300
| +23% | +$3.3M |
|
571
CALL
Archer Daniels Midland
ADM
$40.8B
| $18.8M | 0.01% |
327,300
-113,500
| -26% | -$6.78M |
|
572
PUT
Dick's Sporting Goods
DKS
$12.4B
| $18.8M | 0.01% |
95,000
+40,800
| +75% | +$8.9M |
|
573
CALL
United States Oil Fund
USO
$1.61B
| $18.8M | 0.01% |
271,900
-57,100
| -17% | -$4.03M |
|
574
PUT
Energy Fuels
UUUU
$3.83B
| $18.8M | 0.01% |
1,292,000
+83,400
| +7% | +$1.42M |
|
575
PUT
Estee Lauder
EL
$37.6B
| $18.8M | 0.01% |
179,300
-126,500
| -41% | -$12.3M |
|
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's Q4 2025 filing shows 1,476 new, 2,599 increased, 4,088 reduced and 2,184 closed positions. Its largest new stake was Western Digital: 341,762 shares worth $58.9M. The largest sale was NVIDIA, an estimated $262M.
By sector, the portfolio is most concentrated in Miscellaneous at 98% of assets, up from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- 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.