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 | |
|---|---|---|---|---|---|---|
|
AKRO
3326
CALL
DELISTED
Akero Therapeutics
AKRO
| $764K | ﹤0.01% |
16,100
-54,800
| -77% | -$2.65M |
|
3327
PUT
The RealReal
REAL
$1.39B
| $763K | ﹤0.01% |
71,800
-42,900
| -37% | -$317K |
|
3328
PUT
Alkermes
ALKS
$8.53B
| $762K | ﹤0.01% |
25,400
+25,200
| +12,600% | +$711K |
|
3329
Black Hills Corp
BKH
$5.75B
| $762K | ﹤0.01% |
12,387
+10,782
| +672% | +$634K |
|
3330
CALL
EVgo
EVGO
$223M
| $762K | ﹤0.01% |
161,200
-18,900
| -10% | -$73.2K |
|
3331
PUT
Unum
UNM
$14B
| $762K | ﹤0.01% |
9,800
-13,300
| -58% | -$997K |
|
|
FFAI
3332
PUT
Faraday Future Intelligent Electric
FFAI
$9.56M
| $761K | ﹤0.01% |
3,903
-2,349
| -38% | -$744K |
|
3333
NEOS S&P 500 High Income ETF
SPYI
$10.7B
| $760K | ﹤0.01% |
+14,539
| New | +$747K |
|
|
VISN
3334
Vistance Networks Inc
VISN
$2.6B
| $759K | ﹤0.01% |
49,044
-308,088
| -86% | -$4M |
|
3335
Warrior Met Coal
HCC
$4.17B
| $759K | ﹤0.01% |
11,929
+7,404
| +164% | +$423K |
|
3336
PUT
Ecopetrol
EC
$31.7B
| $758K | ﹤0.01% |
82,400
+34,700
| +73% | +$311K |
|
|
KYIV
3337
PUT
Kyivstar Group
KYIV
$3.14B
| $757K | ﹤0.01% |
+60,600
| New | +$720K |
|
3338
CALL
Martin Marietta Materials
MLM
$34.6B
| $756K | ﹤0.01% |
1,200
-200
| -14% | -$119K |
|
3339
Smith & Wesson
SWBI
$669M
| $756K | ﹤0.01% |
76,949
+33,930
| +79% | +$290K |
|
3340
CALL
Cogent Communications
CCOI
$641M
| $755K | ﹤0.01% |
19,700
+9,600
| +95% | +$401K |
|
3341
Scholastic
SCHL
$765M
| $755K | ﹤0.01% |
27,575
+27,367
| +13,157% | +$677K |
|
3342
CALL
Crane Co
CR
$13B
| $754K | ﹤0.01% |
4,100
+3,400
| +486% | +$641K |
|
3343
CALL
Xeris Biopharma Holdings
XERS
$1.42B
| $753K | ﹤0.01% |
92,600
+56,400
| +156% | +$375K |
|
3344
PUT
Nabors Industries
NBR
$1.14B
| $752K | ﹤0.01% |
18,400
+17,200
| +1,433% | +$612K |
|
3345
CALL
Ichor Holdings
ICHR
$2.37B
| $751K | ﹤0.01% |
42,900
+42,600
| +14,200% | +$809K |
|
3346
ProShares Ether Strategy ETF
EETH
$54.8M
| $749K | ﹤0.01% |
+11,039
| New | +$746K |
|
3347
PUT
MarketAxess Holdings
MKTX
$4.3B
| $749K | ﹤0.01% |
4,300
+4,000
| +1,333% | +$782K |
|
|
EFOR
3348
PUT
Everforth Inc
EFOR
$960M
| $748K | ﹤0.01% |
15,800
+15,700
| +15,700% | +$801K |
|
3349
PUT
AtaiBeckley Inc
ATAI
$2.65B
| $748K | ﹤0.01% |
141,400
+67,600
| +92% | +$275K |
|
|
GES
3350
CALL
DELISTED
Guess Inc
GES
| $748K | ﹤0.01% |
44,800
-10,900
| -20% | -$161K |
|
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.