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 | |
|---|---|---|---|---|---|---|
276
PUT
Comcast
CMCSA
$84B
| $52.7M | 0.03% |
1,761,800
+1,093,100
| +163% | +$31.2M |
|
277
CALL
AT&T
T
$160B
| $52.4M | 0.03% |
2,111,000
+519,700
| +33% | +$13.2M |
|
278
CALL
McDonald's
MCD
$187B
| $52.3M | 0.03% |
171,200
-17,300
| -9% | -$5.3M |
|
279
CALL
Rocket Companies
RKT
$38B
| $52.3M | 0.03% |
2,702,300
-528,100
| -16% | -$9.44M |
|
280
PUT
Newmont
NEM
$102B
| $52.1M | 0.03% |
521,400
-502,600
| -49% | -$45.4M |
|
281
CALL
Bristol-Myers Squibb
BMY
$124B
| $52M | 0.03% |
964,500
-421,600
| -30% | -$20.3M |
|
282
Direxion Daily Semiconductor Bull 3X ETF
SOXL
$22B
| $52M | 0.03% |
1,236,517
+354,575
| +40% | +$14.8M |
|
283
PUT
ServiceNow
NOW
$98.4B
| $51.8M | 0.03% |
337,900
+1,900
| +0.6% | +$326K |
|
284
CALL
NextEra Energy
NEE
$186B
| $51.8M | 0.03% |
644,700
-110,700
| -15% | -$9.17M |
|
|
NVO
285
Novo Nordisk
NVO
$213B
| $51.8M | 0.03% |
1,017,162
+421,560
| +71% | +$21.6M |
|
|
ECHO
286
CALL
EchoStar
ECHO
$26.7B
| $51.7M | 0.03% |
475,300
-244,900
| -34% | -$19.9M |
|
287
CALL
Moderna
MRNA
$23B
| $51.2M | 0.03% |
1,734,500
+142,500
| +9% | +$3.87M |
|
|
288
PUT
NextEra Energy
NEE
$186B
| $51M | 0.03% |
635,000
-15,900
| -2% | -$1.32M |
|
289
CALL
TeraWulf
WULF
$9.66B
| $50.7M | 0.03% |
4,416,100
-559,900
| -11% | -$7.51M |
|
290
CALL
Marathon Digital Holdings
MARA
$4.73B
| $50.5M | 0.03% |
5,626,900
+149,000
| +3% | +$2.2M |
|
291
PUT
Chipotle Mexican Grill
CMG
$41.3B
| $50.4M | 0.03% |
1,362,800
+295,500
| +28% | +$10.7M |
|
292
PUT
FedEx
FDX
$76.6B
| $50.3M | 0.03% |
174,200
-19,300
| -10% | -$5.07M |
|
293
PUT
Astera Labs
ALAB
$56.7B
| $49.9M | 0.03% |
299,700
-171,500
| -36% | -$28.7M |
|
294
CALL
NIO
NIO
$11.7B
| $49.7M | 0.03% |
9,741,900
-361,300
| -4% | -$2.23M |
|
295
CALL
Blackstone
BX
$150B
| $49.3M | 0.03% |
319,900
-128,700
| -29% | -$19.6M |
|
296
PUT
JD.com
JD
$40.7B
| $49.2M | 0.03% |
1,714,400
-1,088,900
| -39% | -$34.1M |
|
297
CALL
Delta Air Lines
DAL
$54.9B
| $49.1M | 0.03% |
707,000
-476,800
| -40% | -$29.8M |
|
|
298
PUT
Bristol-Myers Squibb
BMY
$124B
| $48.8M | 0.03% |
905,600
-649,600
| -42% | -$31.3M |
|
299
PUT
Rigetti Computing
RGTI
$5.06B
| $48.6M | 0.03% |
2,192,600
-811,700
| -27% | -$26.5M |
|
300
CALL
Capital One
COF
$124B
| $48.3M | 0.03% |
199,200
-90,500
| -31% | -$20.1M |
|
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.