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 | |
|---|---|---|---|---|---|---|
|
GRRR
2251
CALL
Gorilla Technology Group
GRRR
$333M
| $2.16M | ﹤0.01% |
117,100
-16,300
| -12% | -$300K |
|
2252
PUT
LendingTree
TREE
$544M
| $2.16M | ﹤0.01% |
33,400
+24,700
| +284% | +$1.42M |
|
2253
CALL
Roper Technologies
ROP
$36.3B
| $2.14M | ﹤0.01% |
4,300
+3,800
| +760% | +$2.03M |
|
2254
CALL
Emcor
EME
$33.1B
| $2.14M | ﹤0.01% |
3,300
+1,300
| +65% | +$789K |
|
|
SMLR
2255
CALL
DELISTED
Semler Scientific
SMLR
| $2.14M | ﹤0.01% |
71,400
-79,600
| -53% | -$2.74M |
|
2256
IQVIA
IQV
$34.7B
| $2.14M | ﹤0.01% |
+11,274
| New | +$2.05M |
|
2257
Blackstone Mortgage Trust
BXMT
$2.82B
| $2.14M | ﹤0.01% |
116,250
+22,172
| +24% | +$428K |
|
2258
PUT
Iron Mountain
IRM
$38.2B
| $2.14M | ﹤0.01% |
21,000
-144,500
| -87% | -$13.9M |
|
2259
PUT
AAR Corp
AIR
$5.15B
| $2.13M | ﹤0.01% |
+23,800
| New | +$1.81M |
|
|
JBS
2260
JBS N.V.
JBS
$40.4B
| $2.13M | ﹤0.01% |
142,980
+127,224
| +807% | +$1.86M |
|
2261
CALL
Vanguard S&P 500 Growth ETF
VOOG
$25.4B
| $2.13M | ﹤0.01% |
29,400
+5,400
| +23% | +$373K |
|
|
VSXY
2262
PUT
Victoria's Secret
VSXY
$6.64B
| $2.13M | ﹤0.01% |
78,500
-99,700
| -56% | -$2.24M |
|
2263
CALL
Entergy
ETR
$54.1B
| $2.12M | ﹤0.01% |
22,800
+3,800
| +20% | +$334K |
|
2264
Invesco CurrencyShares Euro Currency Trust
FXE
$331M
| $2.12M | ﹤0.01% |
19,592
+14,628
| +295% | +$1.58M |
|
2265
GitLab
GTLB
$5.28B
| $2.12M | ﹤0.01% |
47,065
-26,630
| -36% | -$1.22M |
|
2266
PUT
Darling Ingredients
DAR
$9.93B
| $2.12M | ﹤0.01% |
68,700
-121,300
| -64% | -$4.05M |
|
|
GTM
2267
ZoomInfo Technologies
GTM
$861M
| $2.12M | ﹤0.01% |
194,080
+63,087
| +48% | +$676K |
|
2268
PUT
Brinker International
EAT
$8.02B
| $2.12M | ﹤0.01% |
16,700
-5,900
| -26% | -$921K |
|
2269
Idexx Laboratories
IDXX
$42.9B
| $2.11M | ﹤0.01% |
+3,310
| New | +$2.01M |
|
2270
PUT
Navitas Semiconductor
NVTS
$2.66B
| $2.11M | ﹤0.01% |
292,500
-305,400
| -51% | -$2.04M |
|
2271
CALL
ProShares UltraShort Health Care
RXD
$3.25M
| $2.11M | ﹤0.01% |
32,350
+6,500
| +25% | +$157K |
|
2272
PUT
Winnebago Industries
WGO
$870M
| $2.11M | ﹤0.01% |
63,100
+37,300
| +145% | +$1.23M |
|
2273
CALL
Cboe Global Markets
CBOE
$29.8B
| $2.11M | ﹤0.01% |
8,600
-11,200
| -57% | -$2.69M |
|
2274
PUT
Bruker
BRKR
$9.2B
| $2.11M | ﹤0.01% |
64,900
-1,000
| -2% | -$35.6K |
|
2275
Galicia Financial Group
GGAL
$7.92B
| $2.11M | ﹤0.01% |
76,518
+54,622
| +249% | +$2.35M |
|
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.