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 | |
|---|---|---|---|---|---|---|
701
CALL
W.W. Grainger
GWW
$64.6B
| $17.3M | 0.01% |
18,200
-8,000
| -31% | -$8.03M |
|
702
CALL
DuPont de Nemours
DD
$18.6B
| $17.3M | 0.01% |
176,541
-76,082
| -30% | -$7.17M |
|
703
CALL
Oneok
OKE
$58.7B
| $17.3M | 0.01% |
236,500
+91,100
| +63% | +$6.98M |
|
704
CALL
State Street SPDR Portfolio Short Term Treasury ETF
SPTS
$6.06B
| $17.2M | 0.01% |
172,000
-92,900
| -35% | -$2.72M |
|
705
PUT
Zoom
ZM
$24.7B
| $17.2M | 0.01% |
208,300
-19,200
| -8% | -$1.5M |
|
706
NextEra Energy
NEE
$187B
| $17.1M | 0.01% |
226,693
+106,023
| +88% | +$7.75M |
|
707
CALL
Albemarle
ALB
$13.8B
| $17.1M | 0.01% |
210,900
-35,500
| -14% | -$2.74M |
|
708
CALL
KE Holdings
BEKE
$17.8B
| $17.1M | 0.01% |
898,200
+421,500
| +88% | +$7.9M |
|
709
CALL
Kratos Defense & Security Solutions
KTOS
$9.27B
| $17.1M | 0.01% |
186,700
+13,100
| +8% | +$839K |
|
710
PUT
Howmet Aerospace
HWM
$115B
| $17M | 0.01% |
86,800
+60,200
| +226% | +$11M |
|
711
PUT
Marathon Petroleum
MPC
$91.2B
| $17M | 0.01% |
88,100
+19,000
| +27% | +$3.34M |
|
712
CALL
AB InBev
BUD
$155B
| $16.9M | 0.01% |
283,700
+29,000
| +11% | +$1.82M |
|
713
PUT
HSBC
HSBC
$349B
| $16.9M | 0.01% |
237,900
+92,600
| +64% | +$6.02M |
|
714
PUT
Bilibili
BILI
$7.32B
| $16.8M | 0.01% |
598,700
+120,700
| +25% | +$2.89M |
|
715
CALL
Fluor
FLR
$7.44B
| $16.8M | 0.01% |
399,400
+66,600
| +20% | +$3.07M |
|
716
CALL
Regeneron Pharmaceuticals
REGN
$68.3B
| $16.7M | 0.01% |
29,700
+3,700
| +14% | +$2.09M |
|
717
CALL
Sunrun
RUN
$2.48B
| $16.7M | 0.01% |
965,200
-756,600
| -44% | -$10.1M |
|
|
ETHA
718
iShares Ethereum Trust ETF
ETHA
$5.27B
| $16.5M | 0.01% |
+523,393
| New | +$15.5M |
|
719
Salesforce
CRM
$129B
| $16.5M | 0.01% |
+69,505
| New | +$17.5M |
|
720
CALL
Stanley Black & Decker
SWK
$13.6B
| $16.5M | 0.01% |
221,500
+50,600
| +30% | +$3.71M |
|
721
CALL
Li Auto
LI
$12.3B
| $16.4M | 0.01% |
648,900
+301,100
| +87% | +$7.8M |
|
|
722
CALL
Howmet Aerospace
HWM
$115B
| $16.4M | 0.01% |
83,700
-66,700
| -44% | -$12.2M |
|
723
CALL
Cadence Design Systems
CDNS
$91.1B
| $16.4M | 0.01% |
46,700
-23,300
| -33% | -$8.02M |
|
724
CALL
General Dynamics
GD
$103B
| $16.3M | 0.01% |
47,900
-19,000
| -28% | -$5.99M |
|
725
PUT
US Bancorp Series B Preferred Stock
USB.PRH
$744M
| $16.2M | 0.01% |
336,100
-280,200
| -45% | -$5.72M |
|
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.