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 | |
|---|---|---|---|---|---|---|
5451
DXC Technology
DXC
$1.82B
| $130K | ﹤0.01% |
9,570
+6,271
| +190% | +$89.1K |
|
5452
PUT
Dyne Therapeutics
DYN
$4.7B
| $130K | ﹤0.01% |
10,300
-900
| -8% | -$10.3K |
|
5453
PUT
Intapp
INTA
$2.52B
| $130K | ﹤0.01% |
3,200
-2,200
| -41% | -$95.1K |
|
5454
CALL
Jasper Therapeutics
JSPR
$21M
| $130K | ﹤0.01% |
54,900
+50,800
| +1,239% | +$154K |
|
5455
CALL
Loews
L
$23.9B
| $130K | ﹤0.01% |
1,300
+600
| +86% | +$56.7K |
|
5456
PUT
Matrix Service
MTRX
$326M
| $130K | ﹤0.01% |
+10,000
| New | +$142K |
|
5457
PUT
Sturm, Ruger & Co
RGR
$594M
| $130K | ﹤0.01% |
3,000
-31,400
| -91% | -$1.13M |
|
|
SAIL
5458
PUT
SailPoint Inc
SAIL
$9.51B
| $130K | ﹤0.01% |
5,900
-2,300
| -28% | -$48.2K |
|
5459
PUT
Addus HomeCare
ADUS
$2.16B
| $129K | ﹤0.01% |
1,100
| – | – |
|
|
BDN
5460
Brandywine Realty Trust
BDN
$524M
| $129K | ﹤0.01% |
30,992
+8,029
| +35% | +$33.8K |
|
|
CGAU
5461
CALL
Centerra Gold
CGAU
$3.36B
| $129K | ﹤0.01% |
12,100
-8,500
| -41% | -$67.8K |
|
5462
Red Robin
RRGB
$145M
| $129K | ﹤0.01% |
18,851
+6,279
| +50% | +$40.1K |
|
5463
Petco
WOOF
$797M
| $129K | ﹤0.01% |
33,491
-57,964
| -63% | -$194K |
|
5464
Wrap Technologies
WRAP
$103M
| $129K | ﹤0.01% |
59,877
+17,550
| +41% | +$28.3K |
|
|
AHRT
5465
CALL
AH Realty Trust
AHRT
$529M
| $128K | ﹤0.01% |
18,300
+15,900
| +663% | +$113K |
|
5466
ASP Isotopes
ASPI
$504M
| $128K | ﹤0.01% |
13,397
-226,753
| -94% | -$2.09M |
|
5467
CALL
Calix
CALX
$2.26B
| $128K | ﹤0.01% |
2,100
-600
| -22% | -$34.6K |
|
5468
CALL
Chefs' Warehouse
CHEF
$4.71B
| $128K | ﹤0.01% |
2,200
-700
| -24% | -$44.6K |
|
5469
PUT
LifeMD
LFMD
$169M
| $128K | ﹤0.01% |
18,900
-37,400
| -66% | -$309K |
|
|
MAXN
5470
CALL
DELISTED
Maxeon Solar Technologies
MAXN
| $128K | ﹤0.01% |
38,400
-500
| -1% | -$1.95K |
|
5471
Teekay Tankers
TNK
$2.75B
| $128K | ﹤0.01% |
2,538
-354
| -12% | -$16.8K |
|
5472
CALL
Cellebrite
CLBT
$3.68B
| $127K | ﹤0.01% |
6,900
-9,000
| -57% | -$141K |
|
5473
PUT
DTE Energy
DTE
$29.5B
| $127K | ﹤0.01% |
900
-900
| -50% | -$123K |
|
|
EFC
5474
CALL
Ellington Financial
EFC
$1.67B
| $127K | ﹤0.01% |
9,800
-8,400
| -46% | -$112K |
|
5475
Fuel Tech
FTEK
$43.9M
| $127K | ﹤0.01% |
42,501
+19,590
| +86% | +$56.8K |
|
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.