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 |
Microsoft
MSFT
|
+$234M |
| 2 |
iShares Russell 2000 ETF
IWM
|
+$97.5M |
| 3 |
Amazon
AMZN
|
+$96.8M |
| 4 |
iShares Bitcoin Trust
IBIT
|
+$80.6M |
| 5 |
Pinduoduo
PDD
|
+$54.9M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$129M |
| 2 |
Alphabet (Google) Class A
GOOGL
|
+$92.9M |
| 3 |
Broadcom
AVGO
|
+$82.9M |
| 4 |
Alphabet (Google) Class C
GOOG
|
+$68.4M |
| 5 |
Meta Platforms (Facebook)
META
|
+$59.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.79% |
| 2 | Consumer Discretionary | 0.3% |
| 3 | Healthcare | 0.25% |
| 4 | Financials | 0.17% |
| 5 | Industrials | 0.09% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
3176
PUT
Leonardo DRS
DRS
$12.9B
| $889K | ﹤0.01% |
19,600
+10,300
| +111% | +$449K |
|
|
NNE
3177
Nano Nuclear Energy
NNE
$875M
| $888K | ﹤0.01% |
+23,052
| New | +$819K |
|
3178
CALL
Revolution Medicines
RVMD
$40B
| $887K | ﹤0.01% |
19,000
+4,900
| +35% | +$192K |
|
3179
PUT
Concentrix
CNXC
$1.5B
| $886K | ﹤0.01% |
19,200
+12,400
| +182% | +$661K |
|
|
NAK
3180
PUT
Northern Dynasty Minerals
NAK
$857M
| $886K | ﹤0.01% |
739,000
+250,900
| +51% | +$270K |
|
3181
PUT
Northern Oil and Gas
NOG
$2.21B
| $885K | ﹤0.01% |
35,700
+21,400
| +150% | +$568K |
|
3182
New Oriental
EDU
$7.94B
| $884K | ﹤0.01% |
16,676
+13,961
| +514% | +$689K |
|
3183
Interactive Brokers
IBKR
$41.1B
| $883K | ﹤0.01% |
+12,841
| New | +$808K |
|
3184
CALL
SLM Corp
SLM
$4.78B
| $882K | ﹤0.01% |
31,900
-176,400
| -85% | -$5.51M |
|
3185
PUT
NextNav
NN
$1.73B
| $879K | ﹤0.01% |
61,500
-233,000
| -79% | -$3.68M |
|
3186
PUT
American Superconductor
AMSC
$1.48B
| $878K | ﹤0.01% |
14,800
-7,000
| -32% | -$350K |
|
3187
PUT
EVgo
EVGO
$220M
| $878K | ﹤0.01% |
185,700
+42,400
| +30% | +$164K |
|
3188
PUT
Perella Weinberg Partners
PWP
$1.18B
| $878K | ﹤0.01% |
+41,200
| New | +$881K |
|
3189
Palladyne AI
PDYN
$244M
| $877K | ﹤0.01% |
102,163
+61,097
| +149% | +$507K |
|
3190
CALL
Barnes & Noble Education
BNED
$445M
| $876K | ﹤0.01% |
88,100
+85,500
| +3,288% | +$797K |
|
3191
Semtech
SMTC
$11.3B
| $876K | ﹤0.01% |
12,273
-1,730
| -12% | -$93.9K |
|
3192
Viking Therapeutics
VKTX
$4.05B
| $876K | ﹤0.01% |
33,354
-70,466
| -68% | -$2.1M |
|
3193
CALL
Ero Copper
ERO
$2.73B
| $875K | ﹤0.01% |
43,300
+5,800
| +15% | +$88.3K |
|
3194
Petrobras
PBR
$116B
| $875K | ﹤0.01% |
69,130
+53,470
| +341% | +$672K |
|
3195
Prime Medicine
PRME
$544M
| $874K | ﹤0.01% |
157,897
-35,718
| -18% | -$145K |
|
|
ACB
3196
PUT
Aurora Cannabis
ACB
$170M
| $872K | ﹤0.01% |
146,400
+31,500
| +27% | +$154K |
|
3197
CALL
Lantheus
LNTH
$7.03B
| $871K | ﹤0.01% |
17,000
-19,800
| -54% | -$1.24M |
|
3198
PUT
Neurocrine Biosciences
NBIX
$17.7B
| $870K | ﹤0.01% |
6,200
+5,600
| +933% | +$759K |
|
3199
National Fuel Gas
NFG
$7.67B
| $870K | ﹤0.01% |
+9,424
| New | +$822K |
|
3200
CALL
Patterson-UTI
PTEN
$3.57B
| $869K | ﹤0.01% |
167,800
+67,700
| +68% | +$389K |
|
Similar funds
Simplex Trading's Q3 2025 Portfolio in Review
As of Q3 2025, Simplex Trading held 10,358 positions worth $195B, up 12% from $175B the previous quarter. Its ten largest holdings account for 46% of the portfolio.
Simplex Trading's Q3 2025 filing shows 1,743 new, 3,828 increased, 3,250 reduced and 1,308 closed positions. Its largest new stake was Microsoft: 458,309 shares worth $237M. The largest sale was iShares 20+ Year Treasury Bond ETF, an estimated $129M.
By sector, the portfolio is most concentrated in Technology at 0.79% of assets, up from 0.74% a quarter earlier, followed by Consumer Discretionary and Healthcare.
- Simplex Trading's largest Q3 2025 buy was Microsoft: 458,309 shares worth $237M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q3 2025, an estimated $97.5M increase.
- Simplex Trading's biggest Q3 2025 reduction was Alphabet (Google) Class A, cutting an estimated $92.9M.
- Simplex Trading fully exited iShares 20+ Year Treasury Bond ETF in Q3 2025, selling an estimated $129M.
- Simplex Trading's ten largest holdings make up 46% of its $195B portfolio in Q3 2025.
- Simplex Trading opened 1,743 new positions and closed 1,308 in Q3 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $195B.
Based on Simplex Trading's 13F filing for Q3 2025, filed 12 Nov 2025.