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 | |
|---|---|---|---|---|---|---|
3751
CALL
CareTrust REIT
CTRE
$10.1B
| $318K | ﹤0.01% |
8,800
+6,100
| +226% | +$219K |
|
|
SEE
3752
DELISTED
Sealed Air
SEE
| $318K | ﹤0.01% |
+7,678
| New | +$297K |
|
3753
PUT
Hess Midstream
HESM
$5.13B
| $317K | ﹤0.01% |
9,200
+500
| +6% | +$16.8K |
|
3754
CALL
Arhaus
ARHS
$1.12B
| $317K | ﹤0.01% |
28,300
-2,400
| -8% | -$24.9K |
|
3755
CALL
AXT Inc
AXTI
$2.8B
| $317K | ﹤0.01% |
19,400
-10,700
| -36% | -$103K |
|
3756
Masco
MAS
$16.5B
| $317K | ﹤0.01% |
+4,994
| New | +$324K |
|
|
BZAI
3757
CALL
Blaize Holdings
BZAI
$122M
| $316K | ﹤0.01% |
162,300
+52,500
| +48% | +$170K |
|
3758
PUT
J&J Snack Foods
JJSF
$1.49B
| $316K | ﹤0.01% |
3,500
| – | – |
|
3759
PUT
Meritage Homes
MTH
$4.89B
| $316K | ﹤0.01% |
4,800
-39,600
| -89% | -$2.74M |
|
3760
Savers
SVV
$1.58B
| $315K | ﹤0.01% |
+33,718
| New | +$347K |
|
|
SMLR
3761
DELISTED
Semler Scientific
SMLR
| $315K | ﹤0.01% |
20,575
-16,931
| -45% | -$384K |
|
3762
CALL
Toro Corp
TORO
$176M
| $314K | ﹤0.01% |
+59,500
| New | +$258K |
|
3763
CALL
Dorian LPG
LPG
$1.9B
| $314K | ﹤0.01% |
12,900
-13,500
| -51% | -$354K |
|
3764
CALL
Copa Holdings
CPA
$5.71B
| $314K | ﹤0.01% |
2,600
-6,300
| -71% | -$771K |
|
3765
Equity Lifestyle Properties
ELS
$12.8B
| $313K | ﹤0.01% |
5,171
+1,429
| +38% | +$88.3K |
|
|
GOLD
3766
CALL
Gold.com Inc
GOLD
$1.18B
| $313K | ﹤0.01% |
9,200
+100
| +1% | +$2.86K |
|
|
LTC
3767
CALL
LTC Properties
LTC
$2.14B
| $313K | ﹤0.01% |
9,100
-400
| -4% | -$14.1K |
|
3768
YieldMax TSLA Option Income Strategy ETF
TSLY
$624M
| $313K | ﹤0.01% |
+8,334
| New | +$337K |
|
3769
PUT
Portland General Electric
POR
$5.92B
| $312K | ﹤0.01% |
6,500
-2,600
| -29% | -$123K |
|
3770
Radiant Logistics
RLGT
$411M
| $312K | ﹤0.01% |
49,224
+41,752
| +559% | +$259K |
|
3771
PUT
GoodRx Holdings
GDRX
$1.06B
| $311K | ﹤0.01% |
114,900
+97,800
| +572% | +$321K |
|
3772
CALL
Ocugen
OCGN
$420M
| $311K | ﹤0.01% |
230,600
+54,700
| +31% | +$77.9K |
|
|
AIRL
3773
PUT
DELISTED
Themes Airlines ETF
AIRL
| $310K | ﹤0.01% |
21,500
-4,500
| -17% | -$65K |
|
3774
Centuri Holdings
CTRI
$2.63B
| $310K | ﹤0.01% |
12,280
+11,730
| +2,133% | +$262K |
|
3775
PUT
Buckle
BKE
$2.35B
| $310K | ﹤0.01% |
5,800
+4,300
| +287% | +$240K |
|
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.