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 | |
|---|---|---|---|---|---|---|
801
PUT
Duke Energy
DUK
$101B
| $10.7M | 0.01% |
91,600
+20,000
| +28% | +$2.44M |
|
802
CALL
Invesco
IVZ
$13.3B
| $10.7M | 0.01% |
408,200
+232,800
| +133% | +$5.69M |
|
|
METD
803
CALL
Direxion Daily META Bear 1X ETF
METD
$8.39M
| $10.7M | 0.01% |
557,200
+74,200
| +15% | +$1.18M |
|
804
CALL
Synchrony
SYF
$23.2B
| $10.7M | 0.01% |
128,500
+77,900
| +154% | +$5.95M |
|
805
CALL
Transocean
RIG
$5.9B
| $10.7M | 0.01% |
2,589,900
+415,900
| +19% | +$1.61M |
|
806
CALL
ON Semiconductor
ON
$34.5B
| $10.7M | 0.01% |
197,500
+29,800
| +18% | +$1.53M |
|
807
American Airlines Group
AAL
$9.07B
| $10.7M | 0.01% |
696,625
+315,057
| +83% | +$4.25M |
|
808
CALL
e.l.f. Beauty
ELF
$4.48B
| $10.7M | 0.01% |
140,100
-2,500
| -2% | -$246K |
|
809
CALL
Phillips 66
PSX
$83.6B
| $10.6M | 0.01% |
82,500
+2,200
| +3% | +$296K |
|
810
CALL
Brighthouse Financial
BHF
$3.6B
| $10.6M | 0.01% |
164,000
+11,200
| +7% | +$658K |
|
|
FIG
811
CALL
Figma
FIG
$10.6B
| $10.6M | 0.01% |
284,200
-164,400
| -37% | -$7.43M |
|
812
FedEx
FDX
$74.5B
| $10.6M | 0.01% |
36,761
+26,180
| +247% | +$6.88M |
|
813
CALL
American Electric Power
AEP
$73.3B
| $10.6M | 0.01% |
92,000
+12,000
| +15% | +$1.42M |
|
814
CALL
DigitalOcean
DOCN
$15.6B
| $10.6M | 0.01% |
220,200
+46,000
| +26% | +$2.03M |
|
|
XIFR
815
CALL
XPLR Infrastructure LP
XIFR
$1.18B
| $10.6M | 0.01% |
1,056,600
+319,500
| +43% | +$3.1M |
|
|
TLN
816
PUT
Talen Energy Corp
TLN
$18B
| $10.5M | 0.01% |
28,100
+12,200
| +77% | +$4.74M |
|
817
CALL
dLocal
DLO
$4.11B
| $10.5M | 0.01% |
744,900
+313,800
| +73% | +$4.43M |
|
818
Lyft
LYFT
$5.3B
| $10.5M | 0.01% |
543,126
+332,078
| +157% | +$6.9M |
|
|
TYNS
819
CALL
DELISTED
Direxion Daily 7-10 Year Treasury Bear 1X Shares
TYNS
| $10.5M | 0.01% |
62,600
+3,700
| +6% | +$620K |
|
820
PUT
APA Corp
APA
$13B
| $10.5M | 0.01% |
428,500
+54,100
| +14% | +$1.31M |
|
|
821
PUT
Synchrony
SYF
$23.2B
| $10.5M | 0.01% |
125,500
+77,300
| +160% | +$5.91M |
|
822
CALL
POET Technologies
POET
$1.31B
| $10.5M | 0.01% |
1,654,000
+355,900
| +27% | +$2.26M |
|
823
PUT
Ares Management
ARES
$27.3B
| $10.4M | 0.01% |
64,600
+39,800
| +160% | +$6.2M |
|
|
CDTX
824
CALL
DELISTED
Cidara Therapeutics
CDTX
| $10.4M | 0.01% |
47,200
+27,000
| +134% | +$4.36M |
|
825
CALL
Chewy
CHWY
$8.4B
| $10.4M | 0.01% |
315,200
-154,200
| -33% | -$5.35M |
|
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.