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 | |
|---|---|---|---|---|---|---|
2351
Harrow
HROW
$1.43B
| $1.94M | ﹤0.01% |
40,360
+32,239
| +397% | +$1.21M |
|
2352
PUT
Core & Main
CNM
$8.17B
| $1.94M | ﹤0.01% |
36,100
+32,200
| +826% | +$1.95M |
|
2353
PUT
ZTO Express
ZTO
$18.2B
| $1.94M | ﹤0.01% |
101,200
-50,800
| -33% | -$973K |
|
2354
CALL
Ultragenyx Pharmaceutical
RARE
$2.65B
| $1.94M | ﹤0.01% |
64,500
-48,400
| -43% | -$1.45M |
|
2355
Vanguard Emerging Markets Government Bond ETF
VWOB
$6.15B
| $1.94M | ﹤0.01% |
+29,001
| New | +$1.91M |
|
|
ETHW
2356
Bitwise Ethereum ETF
ETHW
$195M
| $1.94M | ﹤0.01% |
65,068
+63,996
| +5,970% | +$1.8M |
|
2357
Coherent
COHR
$55.2B
| $1.94M | ﹤0.01% |
+17,998
| New | +$1.79M |
|
|
FLY
2358
PUT
Firefly Aerospace
FLY
$3.23B
| $1.94M | ﹤0.01% |
+66,100
| New | +$2.97M |
|
|
APPX
2359
CALL
Tradr 2X Long APP Daily ETF
APPX
$57M
| $1.94M | ﹤0.01% |
17,800
+16,700
| +1,518% | +$1.12M |
|
|
CDTX
2360
CALL
DELISTED
Cidara Therapeutics
CDTX
| $1.93M | ﹤0.01% |
20,200
-32,300
| -62% | -$2.06M |
|
|
XNET
2361
CALL
Xunlei
XNET
$351M
| $1.93M | ﹤0.01% |
202,000
+195,300
| +2,915% | +$1.2M |
|
2362
PUT
Infosys
INFY
$45B
| $1.92M | ﹤0.01% |
118,300
+104,800
| +776% | +$1.8M |
|
2363
CALL
United States Antimony
UAMY
$766M
| $1.92M | ﹤0.01% |
309,600
+234,900
| +314% | +$982K |
|
2364
CALL
AAR Corp
AIR
$5.15B
| $1.92M | ﹤0.01% |
+21,400
| New | +$1.63M |
|
|
FRMM
2365
CALL
Forum Markets
FRMM
$75.7M
| $1.92M | ﹤0.01% |
+79,570
| New | +$2.38M |
|
|
KC
2366
PUT
Kingsoft Cloud Holdings
KC
$2.84B
| $1.92M | ﹤0.01% |
128,500
+125,800
| +4,659% | +$1.82M |
|
2367
CALL
M&T Bank
MTB
$36.2B
| $1.92M | ﹤0.01% |
9,700
-6,700
| -41% | -$1.31M |
|
2368
CALL
MasTec
MTZ
$26.7B
| $1.92M | ﹤0.01% |
9,000
-1,200
| -12% | -$220K |
|
2369
PG&E
PCG
$47.8B
| $1.91M | ﹤0.01% |
126,981
-672,887
| -84% | -$9.81M |
|
2370
Clover Health Investments
CLOV
$2.28B
| $1.91M | ﹤0.01% |
624,470
+229,049
| +58% | +$654K |
|
2371
Rivian
RIVN
$22.9B
| $1.91M | ﹤0.01% |
+130,172
| New | +$1.74M |
|
2372
PUT
Ferguson
FERG
$44.7B
| $1.91M | ﹤0.01% |
8,500
-33,100
| -80% | -$7.49M |
|
2373
Hasbro
HAS
$12.6B
| $1.91M | ﹤0.01% |
25,146
-7,415
| -23% | -$575K |
|
2374
PUT
ALPS REIT Dividend Dogs ETF
RDOG
$11.6M
| $1.91M | ﹤0.01% |
40,700
+20,600
| +102% | +$755K |
|
2375
MBIA
MBI
$288M
| $1.9M | ﹤0.01% |
255,640
+207,457
| +431% | +$1.32M |
|
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.