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 | |
|---|---|---|---|---|---|---|
6101
VanEck Mortgage REIT Income ETF
MORT
$364M
| $72K | ﹤0.01% |
6,758
+4,512
| +201% | +$48.6K |
|
6102
ProShares UltraShort Real Estate
SRS
$15.2M
| $72K | ﹤0.01% |
1,581
-3,686
| -70% | -$174K |
|
6103
Trupanion
TRUP
$1.07B
| $72K | ﹤0.01% |
1,678
+1,180
| +237% | +$56.1K |
|
|
VMEO
6104
PUT
DELISTED
Vimeo
VMEO
| $72K | ﹤0.01% |
9,300
+6,800
| +272% | +$33.5K |
|
|
KIDZ
6105
CALL
KIDZ AI Inc Class B
KIDZ
$1.24M
| $72K | ﹤0.01% |
120
+111
| +1,233% | +$98.6K |
|
6106
CALL
Ardagh Metal Packaging
AMBP
$2.9B
| $71K | ﹤0.01% |
18,000
+15,600
| +650% | +$62.1K |
|
6107
PUT
Associated Banc-Corp
ASB
$5.8B
| $71K | ﹤0.01% |
2,800
+800
| +40% | +$20.5K |
|
6108
CALL
Custom Truck One Source
CTOS
$2.26B
| $71K | ﹤0.01% |
11,100
+5,400
| +95% | +$31.3K |
|
6109
CALL
Equillium
EQ
$147M
| $71K | ﹤0.01% |
+49,900
| New | +$52.8K |
|
6110
PUT
Graham Corp
GHM
$1.1B
| $71K | ﹤0.01% |
+1,300
| New | +$66.5K |
|
6111
Goosehead Insurance
GSHD
$2.27B
| $71K | ﹤0.01% |
958
+927
| +2,990% | +$81.7K |
|
6112
Helix Energy Solutions
HLX
$1.36B
| $71K | ﹤0.01% |
10,839
+3,360
| +45% | +$21.1K |
|
6113
CALL
Inseego
INSG
$111M
| $71K | ﹤0.01% |
4,800
-25,600
| -84% | -$258K |
|
6114
CALL
PROG Holdings
PRG
$1.71B
| $71K | ﹤0.01% |
2,200
+400
| +22% | +$13.1K |
|
6115
U-Haul Holding Co Series N
UHAL.B
$12.3B
| $71K | ﹤0.01% |
1,404
+981
| +232% | +$52.2K |
|
6116
United Therapeutics
UTHR
$26.2B
| $71K | ﹤0.01% |
+171
| New | +$57.5K |
|
6117
CALL
Buckle
BKE
$2.27B
| $70K | ﹤0.01% |
1,200
-900
| -43% | -$48.7K |
|
6118
Mohawk Industries
MHK
$7.29B
| $70K | ﹤0.01% |
+550
| New | +$68.1K |
|
6119
Neogen
NEOG
$2.51B
| $70K | ﹤0.01% |
12,371
-87,657
| -88% | -$468K |
|
6120
Construction Partners
ROAD
$5.75B
| $70K | ﹤0.01% |
+557
| New | +$63.6K |
|
6121
CALL
Revolve Group
RVLV
$1.82B
| $70K | ﹤0.01% |
3,300
-30,200
| -90% | -$659K |
|
6122
CALL
UDR
UDR
$12.3B
| $70K | ﹤0.01% |
1,900
-800
| -30% | -$31.2K |
|
6123
Vitesse Energy
VTS
$636M
| $70K | ﹤0.01% |
3,043
-33
| -1% | -$811 |
|
6124
CALL
WidePoint Corp
WYY
$97M
| $70K | ﹤0.01% |
14,200
+13,700
| +2,740% | +$55.6K |
|
6125
PUT
ArcBest
ARCB
$3.17B
| $69K | ﹤0.01% |
1,000
+500
| +100% | +$37.6K |
|
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.