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 | |
|---|---|---|---|---|---|---|
3876
PUT
Transportadora de Gas del Sur
TGS
$4.44B
| $483K | ﹤0.01% |
23,000
-3,000
| -12% | -$77.6K |
|
3877
State Street SPDR S&P 600 Small Cap Growth ETF
SLYG
$5.08B
| $482K | ﹤0.01% |
5,117
+1,626
| +47% | +$150K |
|
3878
CALL
Sonoco
SON
$5.99B
| $482K | ﹤0.01% |
11,200
+8,700
| +348% | +$402K |
|
3879
Invesco Senior Loan ETF
BKLN
$6.97B
| $481K | ﹤0.01% |
+23,028
| New | +$482K |
|
3880
CALL
Ormat Technologies
ORA
$6.05B
| $481K | ﹤0.01% |
5,000
+2,600
| +108% | +$235K |
|
3881
Woodward
WWD
$24.5B
| $481K | ﹤0.01% |
1,907
-17,470
| -90% | -$4.34M |
|
3882
PUT
Antero Midstream
AM
$10.3B
| $480K | ﹤0.01% |
24,700
-5,300
| -18% | -$95.8K |
|
3883
PUT
Goldman Sachs Access US Aggregate Bond ETF
GCOR
$794M
| $480K | ﹤0.01% |
9,200
+8,500
| +1,214% | +$351K |
|
3884
CALL
Murphy Oil
MUR
$5.25B
| $480K | ﹤0.01% |
16,900
-13,200
| -44% | -$333K |
|
|
SOLZ
3885
Solana ETF
SOLZ
$87.4M
| $480K | ﹤0.01% |
21,725
+21,133
| +3,570% | +$440K |
|
3886
CALL
East-West Bancorp
EWBC
$18B
| $479K | ﹤0.01% |
4,500
-1,000
| -18% | -$105K |
|
3887
PUT
Revolve Group
RVLV
$1.92B
| $479K | ﹤0.01% |
22,500
+18,700
| +492% | +$408K |
|
|
MBX
3888
CALL
MBX Biosciences
MBX
$2.86B
| $479K | ﹤0.01% |
27,400
+26,900
| +5,380% | +$360K |
|
3889
Axos Financial
AX
$5.64B
| $478K | ﹤0.01% |
5,656
+2,555
| +82% | +$223K |
|
3890
CALL
HDFC Bank
HDB
$121B
| $478K | ﹤0.01% |
14,000
-166,600
| -92% | -$6.14M |
|
|
3891
PUT
HDFC Bank
HDB
$121B
| $478K | ﹤0.01% |
14,000
| – | – |
|
3892
PUT
Companhia Siderúrgica Nacional
SID
$1.46B
| $478K | ﹤0.01% |
319,300
+1,500
| +0.5% | +$2.16K |
|
3893
CALL
Fidelity Enhanced Large Cap Core ETF
FELC
$7.9B
| $477K | ﹤0.01% |
8,100
-4,200
| -34% | -$150K |
|
3894
PUT
Domo
DOMO
$177M
| $476K | ﹤0.01% |
30,100
-128,600
| -81% | -$1.99M |
|
3895
Spectrum Brands
SPB
$2.08B
| $476K | ﹤0.01% |
9,068
+5,825
| +180% | +$323K |
|
|
MTSR
3896
DELISTED
Metsera Inc
MTSR
| $476K | ﹤0.01% |
9,114
+3,316
| +57% | +$122K |
|
3897
Huntsman Corp
HUN
$2B
| $475K | ﹤0.01% |
52,939
+10,759
| +26% | +$113K |
|
3898
Lightpath Technologies
LPTH
$651M
| $474K | ﹤0.01% |
+59,876
| New | +$267K |
|
3899
CALL
CNA Financial
CNA
$15B
| $473K | ﹤0.01% |
10,200
+10,100
| +10,100% | +$468K |
|
3900
Village Farms International
VFF
$250M
| $473K | ﹤0.01% |
151,175
+130,895
| +645% | +$284K |
|
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.