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 | |
|---|---|---|---|---|---|---|
4676
PUT
Dime Commercial Bancshares
DCOM
$1.79B
| $250K | ﹤0.01% |
8,400
-21,600
| -72% | -$633K |
|
4677
PUT
Harmony Biosciences
HRMY
$2.08B
| $250K | ﹤0.01% |
9,100
+7,500
| +469% | +$258K |
|
4678
CALL
AMN Healthcare
AMN
$1.35B
| $249K | ﹤0.01% |
12,900
-700
| -5% | -$13.7K |
|
|
DHC
4679
Diversified Healthcare Trust
DHC
$2.15B
| $249K | ﹤0.01% |
56,467
+28,968
| +105% | +$110K |
|
4680
PUT
Laser Photonics
LASE
$48.5M
| $249K | ﹤0.01% |
+57,800
| New | +$187K |
|
4681
Reservoir Media
RSVR
$727M
| $249K | ﹤0.01% |
30,624
+26,401
| +625% | +$206K |
|
4682
CALL
Black Stone Minerals
BSM
$3.14B
| $248K | ﹤0.01% |
18,900
-37,100
| -66% | -$467K |
|
4683
Dianthus Therapeutics
DNTH
$5.69B
| $248K | ﹤0.01% |
6,313
+6,207
| +5,856% | +$159K |
|
4684
iShares Russell 1000 ETF
IWB
$47.1B
| $248K | ﹤0.01% |
681
| – | – |
|
4685
PUT
Principal Financial Group
PFG
$24.3B
| $248K | ﹤0.01% |
3,000
+2,700
| +900% | +$216K |
|
4686
CALL
Veru
VERU
$35.5M
| $248K | ﹤0.01% |
65,500
+55,110
| +530% | +$238K |
|
4687
CALL
NRX Pharmaceuticals
NRXP
$138M
| $247K | ﹤0.01% |
75,100
+72,800
| +3,165% | +$208K |
|
4688
PUT
Repay Holdings
RPAY
$335M
| $247K | ﹤0.01% |
47,300
+35,000
| +285% | +$187K |
|
4689
CALL
TAL Education Group
TAL
$6.04B
| $247K | ﹤0.01% |
22,100
-32,700
| -60% | -$352K |
|
4690
PUT
Veritone
VERI
$92.9M
| $247K | ﹤0.01% |
51,300
+25,700
| +100% | +$74.3K |
|
4691
CALL
Apple Hospitality REIT
APLE
$3.97B
| $246K | ﹤0.01% |
20,500
-44,200
| -68% | -$546K |
|
|
ARI
4692
Apollo Commercial Real Estate
ARI
$864M
| $246K | ﹤0.01% |
24,342
-171,637
| -88% | -$1.75M |
|
4693
CALL
Fortress Biotech
FBIO
$111M
| $246K | ﹤0.01% |
66,600
+65,900
| +9,414% | +$167K |
|
4694
PUT
Vulcan Materials
VMC
$36.8B
| $246K | ﹤0.01% |
800
-300
| -27% | -$85.2K |
|
4695
Allegro MicroSystems
ALGM
$7.86B
| $245K | ﹤0.01% |
+8,391
| New | +$271K |
|
4696
PUT
Choice Hotels
CHH
$5.26B
| $245K | ﹤0.01% |
+2,300
| New | +$281K |
|
4697
Monte Rosa Therapeutics
GLUE
$1.82B
| $245K | ﹤0.01% |
+33,113
| New | +$175K |
|
|
XRN
4698
Chiron Real Estate Inc
XRN
$535M
| $245K | ﹤0.01% |
7,283
+6,030
| +481% | +$215K |
|
4699
Ingredion
INGR
$6.42B
| $245K | ﹤0.01% |
2,008
-3,773
| -65% | -$486K |
|
|
NOTE
4700
PUT
DELISTED
FiscalNote
NOTE
| $245K | ﹤0.01% |
53,000
+48,583
| +1,100% | +$314K |
|
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.