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 | |
|---|---|---|---|---|---|---|
1951
PUT
Entegris
ENTG
$19.7B
| $2.92M | ﹤0.01% |
31,600
+3,500
| +12% | +$298K |
|
|
WRD
1952
WeRide Inc
WRD
$1.75B
| $2.92M | ﹤0.01% |
294,782
+30,301
| +11% | +$287K |
|
|
BBBY
1953
CALL
Bed Bath & Beyond
BBBY
$473M
| $2.92M | ﹤0.01% |
327,690
-39,490
| -11% | -$326K |
|
1954
CALL
Cognex
CGNX
$10.3B
| $2.91M | ﹤0.01% |
64,300
+35,800
| +126% | +$1.45M |
|
1955
Alexandria Real Estate Equities
ARE
$8.88B
| $2.9M | ﹤0.01% |
34,852
+5,971
| +21% | +$478K |
|
1956
PUT
Yum! Brands
YUM
$41B
| $2.9M | ﹤0.01% |
19,100
-1,600
| -8% | -$236K |
|
1957
Builders FirstSource
BLDR
$7.84B
| $2.9M | ﹤0.01% |
+23,940
| New | +$3.18M |
|
1958
Goodyear
GT
$2.07B
| $2.9M | ﹤0.01% |
387,640
+266,488
| +220% | +$2.5M |
|
1959
PUT
Summit Therapeutics
SMMT
$10.9B
| $2.9M | ﹤0.01% |
140,300
-95,400
| -40% | -$2.31M |
|
1960
CALL
Royalty Pharma
RPRX
$26.1B
| $2.89M | ﹤0.01% |
81,900
-73,000
| -47% | -$2.64M |
|
1961
PUT
WEC Energy
WEC
$37.7B
| $2.89M | ﹤0.01% |
25,200
-12,600
| -33% | -$1.37M |
|
1962
NexGen Energy
NXE
$6.05B
| $2.88M | ﹤0.01% |
321,798
+41,627
| +15% | +$307K |
|
1963
CALL
Pitney Bowes
PBI
$2.42B
| $2.87M | ﹤0.01% |
251,800
-500
| -0.2% | -$5.82K |
|
1964
PUT
BlackBerry
BB
$5.01B
| $2.87M | ﹤0.01% |
588,700
+340,000
| +137% | +$1.35M |
|
1965
CALL
TETRA Technologies
TTI
$1.23B
| $2.87M | ﹤0.01% |
499,500
+405,000
| +429% | +$1.73M |
|
1966
BILL Holdings
BILL
$4.33B
| $2.87M | ﹤0.01% |
+54,187
| New | +$2.52M |
|
|
K
1967
CALL
DELISTED
Kellanova
K
| $2.87M | ﹤0.01% |
35,000
+7,800
| +29% | +$620K |
|
1968
State Street SPDR S&P MIDCAP 400 ETF Trust
MDY
$27B
| $2.86M | ﹤0.01% |
4,803
+3,213
| +202% | +$1.89M |
|
1969
PUT
LPL Financial
LPLA
$26.3B
| $2.86M | ﹤0.01% |
8,600
+6,200
| +258% | +$2.25M |
|
1970
CALL
Sempra
SRE
$60.8B
| $2.86M | ﹤0.01% |
31,800
-113,100
| -78% | -$9.16M |
|
1971
TMC The Metals Company
TMC
$1.59B
| $2.86M | ﹤0.01% |
448,616
+130,224
| +41% | +$781K |
|
1972
SGHC Ltd
SGHC
$7.3B
| $2.86M | ﹤0.01% |
216,424
+185,814
| +607% | +$2.19M |
|
1973
Mobileye
MBLY
$2.03B
| $2.85M | ﹤0.01% |
202,039
+188,711
| +1,416% | +$2.81M |
|
1974
CALL
Amplify Energy
AMPY
$163M
| $2.85M | ﹤0.01% |
543,200
-150,700
| -22% | -$593K |
|
1975
CALL
CNX Resources
CNX
$4.85B
| $2.84M | ﹤0.01% |
88,500
+17,200
| +24% | +$527K |
|
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.