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 | |
|---|---|---|---|---|---|---|
1726
UiPath
PATH
$5.62B
| $3.77M | ﹤0.01% |
281,401
+205,728
| +272% | +$2.43M |
|
1727
PUT
Republic Services
RSG
$66.7B
| $3.76M | ﹤0.01% |
16,400
+3,300
| +25% | +$774K |
|
1728
PUT
Innodata
INOD
$1.83B
| $3.76M | ﹤0.01% |
48,800
+29,300
| +150% | +$1.48M |
|
1729
CALL
Curtiss-Wright
CW
$27.7B
| $3.75M | ﹤0.01% |
6,900
+4,600
| +200% | +$2.27M |
|
1730
PUT
ASP Isotopes
ASPI
$487M
| $3.74M | ﹤0.01% |
388,500
+197,900
| +104% | +$1.82M |
|
1731
Rubrik
RBRK
$15.1B
| $3.74M | ﹤0.01% |
45,428
+22,193
| +96% | +$1.91M |
|
1732
CALL
Fulgent Genetics
FLGT
$559M
| $3.73M | ﹤0.01% |
165,000
-67,200
| -29% | -$1.38M |
|
1733
CALL
Public Storage
PSA
$60.2B
| $3.73M | ﹤0.01% |
12,900
+10,900
| +545% | +$3.13M |
|
1734
PUT
Teladoc Health
TDOC
$1.58B
| $3.72M | ﹤0.01% |
481,500
-56,200
| -10% | -$439K |
|
|
LAC
1735
PUT
Lithium Americas
LAC
$986M
| $3.71M | ﹤0.01% |
649,500
+486,400
| +298% | +$1.54M |
|
1736
CALL
J.M. Smucker
SJM
$12.6B
| $3.7M | ﹤0.01% |
34,100
-20,300
| -37% | -$2.2M |
|
1737
CALL
Canadian Pacific Kansas City
CP
$82B
| $3.68M | ﹤0.01% |
49,400
-23,700
| -32% | -$1.81M |
|
1738
CVS Health
CVS
$137B
| $3.68M | ﹤0.01% |
+48,791
| New | +$3.34M |
|
1739
CALL
Allstate
ALL
$66.9B
| $3.67M | ﹤0.01% |
17,100
+1,100
| +7% | +$222K |
|
1740
CALL
Equifax
EFX
$20.3B
| $3.67M | ﹤0.01% |
14,300
+5,100
| +55% | +$1.28M |
|
|
HBI
1741
PUT
DELISTED
Hanesbrands
HBI
| $3.67M | ﹤0.01% |
556,300
+387,500
| +230% | +$2.14M |
|
1742
PUT
ArcelorMittal
MT
$50.4B
| $3.66M | ﹤0.01% |
101,300
-26,800
| -21% | -$903K |
|
1743
Cooper-Standard Automotive
CPS
$504M
| $3.66M | ﹤0.01% |
99,133
+35,428
| +56% | +$1.08M |
|
1744
CALL
Sweetgreen
SG
$713M
| $3.66M | ﹤0.01% |
458,700
+78,400
| +21% | +$852K |
|
1745
PUT
Red Cat Holdings
RCAT
$1.16B
| $3.66M | ﹤0.01% |
353,400
+238,000
| +206% | +$2.22M |
|
1746
PUT
Full Truck Alliance
YMM
$9.56B
| $3.65M | ﹤0.01% |
281,700
+43,100
| +18% | +$534K |
|
1747
CALL
Bath & Body Works
BBWI
$4.01B
| $3.65M | ﹤0.01% |
141,700
+47,300
| +50% | +$1.4M |
|
1748
PUT
Medpace
MEDP
$16.8B
| $3.65M | ﹤0.01% |
7,100
-800
| -10% | -$349K |
|
1749
CALL
Progress Software
PRGS
$1.55B
| $3.65M | ﹤0.01% |
83,100
+74,300
| +844% | +$3.42M |
|
1750
CALL
Klaviyo
KVYO
$4.91B
| $3.65M | ﹤0.01% |
131,800
+43,200
| +49% | +$1.4M |
|
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.