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 | |
|---|---|---|---|---|---|---|
901
PUT
SoundHound AI
SOUN
$2.71B
| $11.1M | 0.01% |
688,700
-1,190,400
| -63% | -$15.8M |
|
902
PUT
BigBear.ai
BBAI
$1.37B
| $11M | 0.01% |
1,687,300
-472,500
| -22% | -$3.02M |
|
903
CALL
Veeva Systems
VEEV
$29.2B
| $11M | 0.01% |
36,900
-24,500
| -40% | -$6.9M |
|
904
PUT
American Electric Power
AEP
$73.4B
| $11M | 0.01% |
97,700
+36,200
| +59% | +$3.96M |
|
905
PUT
Cognizant
CTSH
$20.3B
| $11M | 0.01% |
163,800
+60,600
| +59% | +$4.38M |
|
906
PUT
Digital Realty Trust
DLR
$66.4B
| $11M | 0.01% |
63,500
-106,400
| -63% | -$18.2M |
|
907
PUT
Sable Offshore Corp
SOC
$893M
| $11M | 0.01% |
627,900
+448,700
| +250% | +$11.5M |
|
908
PUT
Shell
SHEL
$243B
| $11M | 0.01% |
153,200
-128,200
| -46% | -$9.23M |
|
909
CALL
Cigna
CI
$75.7B
| $10.9M | 0.01% |
37,900
-8,000
| -17% | -$2.37M |
|
910
CALL
Phillips 66
PSX
$83B
| $10.9M | 0.01% |
80,300
-22,800
| -22% | -$2.92M |
|
911
CALL
General Mills
GIS
$19B
| $10.9M | 0.01% |
216,500
+13,100
| +6% | +$657K |
|
912
CALL
Cintas
CTAS
$81.3B
| $10.9M | 0.01% |
53,000
+3,400
| +7% | +$726K |
|
913
CALL
Jabil
JBL
$33.7B
| $10.9M | 0.01% |
50,000
+21,600
| +76% | +$4.7M |
|
|
VISN
914
CALL
Vistance Networks Inc
VISN
$2.69B
| $10.9M | 0.01% |
701,000
+598,000
| +581% | +$7.76M |
|
915
PUT
MetLife
MET
$59.5B
| $10.8M | 0.01% |
131,700
-57,600
| -30% | -$4.53M |
|
916
CALL
Uranium Energy
UEC
$4.86B
| $10.8M | 0.01% |
810,700
+75,300
| +10% | +$753K |
|
917
PUT
Centene
CNC
$31.5B
| $10.8M | 0.01% |
302,500
-33,800
| -10% | -$1.02M |
|
918
PUT
Kohl's
KSS
$2.06B
| $10.8M | 0.01% |
701,200
+224,000
| +47% | +$2.99M |
|
919
CALL
ChargePoint
CHPT
$140M
| $10.7M | 0.01% |
982,600
+932,345
| +1,855% | +$10.7M |
|
920
PUT
Gold Fields
GFI
$28.9B
| $10.7M | 0.01% |
255,700
-113,100
| -31% | -$3.51M |
|
|
TIGR
921
PUT
UP Fintech Holding
TIGR
$870M
| $10.7M | 0.01% |
1,004,800
-361,900
| -26% | -$3.88M |
|
922
CALL
Teck Resources
TECK
$29.3B
| $10.7M | 0.01% |
243,900
-276,400
| -53% | -$10M |
|
923
PUT
BioNTech
BNTX
$23.3B
| $10.7M | 0.01% |
108,500
+52,600
| +94% | +$5.62M |
|
|
924
PUT
Jabil
JBL
$33.7B
| $10.7M | 0.01% |
49,200
+10,400
| +27% | +$2.26M |
|
925
CALL
Realty Income
O
$60.4B
| $10.7M | 0.01% |
175,200
-56,000
| -24% | -$3.26M |
|
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.