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 | |
|---|---|---|---|---|---|---|
6026
Lincoln Educational Services
LINC
$1.33B
| $78K | ﹤0.01% |
3,341
+601
| +22% | +$12.9K |
|
6027
POSCO
PKX
$16.5B
| $78K | ﹤0.01% |
+1,594
| New | +$86K |
|
6028
PUT
Red Robin
RRGB
$144M
| $78K | ﹤0.01% |
11,400
+7,200
| +171% | +$46K |
|
6029
PUT
Senseonics Holdings Inc
SENS
$265M
| $78K | ﹤0.01% |
9,035
+1,895
| +27% | +$18.3K |
|
6030
PUT
Silicon Laboratories
SLAB
$7.15B
| $78K | ﹤0.01% |
600
+400
| +200% | +$54.5K |
|
6031
PUT
Sony
SONY
$134B
| $78K | ﹤0.01% |
127,400
+10,700
| +9% | +$288K |
|
6032
PUT
Warner Music
WMG
$14.4B
| $78K | ﹤0.01% |
2,300
+200
| +10% | +$6.38K |
|
|
DHC
6033
PUT
Diversified Healthcare Trust
DHC
$2.17B
| $77K | ﹤0.01% |
17,600
| – | – |
|
6034
CALL
LGI Homes
LGIH
$1.33B
| $77K | ﹤0.01% |
1,500
-1,400
| -48% | -$81.6K |
|
6035
CALL
Mohawk Industries
MHK
$7.29B
| $77K | ﹤0.01% |
600
-400
| -40% | -$49.5K |
|
|
NIU
6036
Niu Technologies
NIU
$203M
| $77K | ﹤0.01% |
16,508
-11,659
| -41% | -$47.6K |
|
6037
Protara Therapeutics
TARA
$227M
| $77K | ﹤0.01% |
17,890
+16,529
| +1,214% | +$53.5K |
|
6038
CALL
Valmont Industries
VMI
$9.2B
| $77K | ﹤0.01% |
+200
| New | +$72.7K |
|
|
ASMG
6039
Leverage Shares 2X Long ASML Daily ETF
ASMG
$36.4M
| $77K | ﹤0.01% |
3,531
+2,417
| +217% | +$36.2K |
|
6040
CALL
Essent Group
ESNT
$6.12B
| $76K | ﹤0.01% |
1,200
| – | – |
|
6041
CALL
Galectin Therapeutics
GALT
$213M
| $76K | ﹤0.01% |
18,000
+2,800
| +18% | +$10.5K |
|
6042
CALL
Graco
GGG
$13B
| $76K | ﹤0.01% |
900
-200
| -18% | -$17.1K |
|
6043
Home BancShares
HOMB
$6.25B
| $76K | ﹤0.01% |
+2,703
| New | +$78.5K |
|
6044
CALL
Neumora Therapeutics
NMRA
$306M
| $76K | ﹤0.01% |
41,800
+4,000
| +11% | +$6.47K |
|
6045
PUT
Rollins
ROL
$18.5B
| $76K | ﹤0.01% |
1,300
-2,100
| -62% | -$119K |
|
|
SCS
6046
DELISTED
Steelcase
SCS
| $76K | ﹤0.01% |
+4,433
| New | +$64K |
|
6047
CALL
Hafnia
HAFN
$3.84B
| $76K | ﹤0.01% |
12,700
+9,600
| +310% | +$54.9K |
|
6048
Andersons Inc
ANDE
$2.44B
| $75K | ﹤0.01% |
1,899
-48
| -2% | -$1.85K |
|
6049
PUT
Fox Factory Holding Corp
FOXF
$747M
| $75K | ﹤0.01% |
3,100
+1,900
| +158% | +$53.5K |
|
6050
CALL
Monro
MNRO
$421M
| $75K | ﹤0.01% |
4,200
+1,700
| +68% | +$27.9K |
|
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.