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 | |
|---|---|---|---|---|---|---|
5226
CALL
Moelis & Co
MC
$4.97B
| $156K | ﹤0.01% |
2,200
+300
| +16% | +$21.4K |
|
|
LITS
5227
CALL
Lite Strategy Inc
LITS
$32.8M
| $156K | ﹤0.01% |
+64,700
| New | +$267K |
|
5228
PUT
Tyler Technologies
TYL
$12.7B
| $156K | ﹤0.01% |
300
-600
| -67% | -$337K |
|
|
TE
5229
PUT
T1 Energy
TE
$1.16B
| $156K | ﹤0.01% |
71,900
-117,900
| -62% | -$188K |
|
|
ACLX
5230
PUT
DELISTED
Arcellx
ACLX
| $155K | ﹤0.01% |
1,900
-1,000
| -34% | -$72K |
|
5231
PUT
Cato Corp
CATO
$68.3M
| $155K | ﹤0.01% |
+36,900
| New | +$130K |
|
5232
CALL
Energy Recovery
ERII
$446M
| $155K | ﹤0.01% |
10,100
+5,300
| +110% | +$74.7K |
|
5233
CALL
4D Molecular Therapeutics
FDMT
$532M
| $155K | ﹤0.01% |
17,900
+17,500
| +4,375% | +$105K |
|
5234
FLEX LNG
FLNG
$1.69B
| $155K | ﹤0.01% |
+6,173
| New | +$153K |
|
5235
PUT
Murphy USA
MUSA
$11.2B
| $155K | ﹤0.01% |
+400
| New | +$158K |
|
|
NOTE
5236
CALL
DELISTED
FiscalNote
NOTE
| $155K | ﹤0.01% |
33,500
+27,933
| +502% | +$181K |
|
5237
PUT
Simulations Plus
SLP
$369M
| $155K | ﹤0.01% |
10,300
+6,600
| +178% | +$96K |
|
5238
CALL
Trupanion
TRUP
$1.07B
| $155K | ﹤0.01% |
3,600
-9,500
| -73% | -$451K |
|
5239
Frontier Group Holdings
ULCC
$1.55B
| $155K | ﹤0.01% |
+35,172
| New | +$160K |
|
5240
CALL
Vanguard FTSE Developed Markets ETF
VEA
$229B
| $155K | ﹤0.01% |
2,600
-4,800
| -65% | -$280K |
|
|
VTYX
5241
DELISTED
Ventyx Biosciences
VTYX
| $155K | ﹤0.01% |
49,959
-78,945
| -61% | -$209K |
|
|
FMDG
5242
CALL
DELISTED
Fieldstone Merlin Dynamic Large Cap Growth ETF
FMDG
| $155K | ﹤0.01% |
3,300
-3,300
| -50% | -$155K |
|
|
AIV
5243
Aimco
AIV
$387M
| $154K | ﹤0.01% |
19,486
-9,883
| -34% | -$80.3K |
|
5244
CALL
Angi Inc
ANGI
$229M
| $154K | ﹤0.01% |
9,500
-1,100
| -10% | -$18.9K |
|
5245
Teucrium Corn Fund
CORN
$176M
| $154K | ﹤0.01% |
8,861
+748
| +9% | +$13K |
|
5246
Quest Diagnostics
DGX
$25.7B
| $154K | ﹤0.01% |
+811
| New | +$144K |
|
5247
PUT
Hycroft Mining Holding Corp
HYMC
$1.82B
| $154K | ﹤0.01% |
24,900
+21,800
| +703% | +$96.9K |
|
5248
CALL
Lufax Holding
LU
$1.35B
| $154K | ﹤0.01% |
38,000
+22,000
| +138% | +$65.7K |
|
5249
Morgan Stanley Direct Lending Fund
MSDL
$1.24B
| $154K | ﹤0.01% |
9,634
-3,188
| -25% | -$58.1K |
|
5250
PUT
Rezolute
RZLT
$454M
| $154K | ﹤0.01% |
16,400
+15,400
| +1,540% | +$103K |
|
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.