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 | |
|---|---|---|---|---|---|---|
2801
PUT
FerroAtlántica
GSM
$628M
| $1.27M | ﹤0.01% |
278,600
+50,300
| +22% | +$215K |
|
2802
PUT
Array Technologies
ARRY
$818M
| $1.26M | ﹤0.01% |
155,100
+79,100
| +104% | +$599K |
|
|
SEZL
2803
CALL
Sezzle
SEZL
$5.17B
| $1.26M | ﹤0.01% |
15,900
-6,500
| -29% | -$746K |
|
2804
PUT
Universal Display
OLED
$3.71B
| $1.26M | ﹤0.01% |
8,800
+7,000
| +389% | +$1.02M |
|
2805
Skyworks Solutions
SWKS
$9.06B
| $1.26M | ﹤0.01% |
16,414
-2,833
| -15% | -$211K |
|
2806
PUT
Canadian Imperial Bank of Commerce
CM
$107B
| $1.26M | ﹤0.01% |
15,800
+9,200
| +139% | +$692K |
|
2807
PUT
Axos Financial
AX
$5.45B
| $1.26M | ﹤0.01% |
14,900
+2,400
| +19% | +$209K |
|
2808
Citigroup
C
$222B
| $1.26M | ﹤0.01% |
12,430
-110,576
| -90% | -$10.5M |
|
2809
CALL
Hannon Armstrong Sustainable Infrastructure Capital
HASI
$4.9B
| $1.26M | ﹤0.01% |
41,100
+20,800
| +102% | +$574K |
|
2810
CALL
Vulcan Materials
VMC
$36.3B
| $1.26M | ﹤0.01% |
4,100
+2,500
| +156% | +$710K |
|
2811
CALL
Aegon
AEG
$13.5B
| $1.26M | ﹤0.01% |
157,700
+90,800
| +136% | +$678K |
|
2812
PUT
Omega Healthcare
OHI
$15.4B
| $1.26M | ﹤0.01% |
29,800
-72,000
| -71% | -$2.9M |
|
|
CDTX
2813
DELISTED
Cidara Therapeutics
CDTX
| $1.26M | ﹤0.01% |
13,127
-54,903
| -81% | -$3.5M |
|
2814
PUT
Algoma Steel
ASTL
$455M
| $1.26M | ﹤0.01% |
353,500
+252,400
| +250% | +$1.34M |
|
2815
CALL
Schrodinger
SDGR
$1.12B
| $1.25M | ﹤0.01% |
62,600
+14,200
| +29% | +$285K |
|
2816
PUT
Canadian National Railway
CNI
$78.3B
| $1.25M | ﹤0.01% |
13,300
+12,800
| +2,560% | +$1.24M |
|
2817
PUT
Root
ROOT
$917M
| $1.25M | ﹤0.01% |
14,000
-12,300
| -47% | -$1.29M |
|
2818
CALL
Host Hotels & Resorts
HST
$16.8B
| $1.25M | ﹤0.01% |
73,600
-115,600
| -61% | -$1.92M |
|
2819
CALL
CVR Partners
UAN
$1.3B
| $1.25M | ﹤0.01% |
13,900
+1,500
| +12% | +$135K |
|
2820
BioMarin Pharmaceuticals
BMRN
$11.5B
| $1.25M | ﹤0.01% |
+23,096
| New | +$1.32M |
|
2821
PUT
Leidos
LDOS
$14.1B
| $1.25M | ﹤0.01% |
6,600
-10,800
| -62% | -$1.88M |
|
|
NGD
2822
PUT
DELISTED
New Gold Inc
NGD
| $1.25M | ﹤0.01% |
173,500
+89,900
| +108% | +$486K |
|
2823
Performance Food Group
PFGC
$17.5B
| $1.24M | ﹤0.01% |
11,966
+10,330
| +631% | +$1.03M |
|
2824
Marathon Petroleum
MPC
$90.3B
| $1.24M | ﹤0.01% |
6,451
-10,047
| -61% | -$1.77M |
|
2825
Western Alliance Bancorporation
WAL
$9.07B
| $1.24M | ﹤0.01% |
14,332
+9,977
| +229% | +$846K |
|
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.