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 | |
|---|---|---|---|---|---|---|
5976
PUT
Avery Dennison
AVY
$13.1B
| $81K | ﹤0.01% |
500
-1,500
| -75% | -$258K |
|
|
BDN
5977
CALL
Brandywine Realty Trust
BDN
$527M
| $81K | ﹤0.01% |
19,500
+15,700
| +413% | +$66K |
|
5978
CALL
Carter Bankshares
CARE
$757M
| $81K | ﹤0.01% |
+4,200
| New | +$78.3K |
|
|
GAMB
5979
CALL
DELISTED
Gambling.com
GAMB
| $81K | ﹤0.01% |
10,000
+9,300
| +1,329% | +$90K |
|
5980
CALL
Genelux
GNLX
$135M
| $81K | ﹤0.01% |
+19,300
| New | +$68.6K |
|
5981
Goldman Sachs ETF Trust Goldman Sachs S&P 500 Premium Income ETF
GPIX
$4.88B
| $81K | ﹤0.01% |
+1,554
| New | +$78.9K |
|
5982
PUT
Gates Industrial Corporation Ltd.
GTES
$6.77B
| $81K | ﹤0.01% |
3,300
+1,700
| +106% | +$42.2K |
|
5983
Intrepid Potash
IPI
$465M
| $81K | ﹤0.01% |
2,657
+1,659
| +166% | +$52.2K |
|
5984
CALL
Manhattan Associates
MANH
$11B
| $81K | ﹤0.01% |
400
-3,700
| -90% | -$782K |
|
5985
CALL
MBIA
MBI
$274M
| $81K | ﹤0.01% |
10,900
+6,700
| +160% | +$42.5K |
|
|
ORC
5986
CALL
Orchid Island Capital
ORC
$1.3B
| $81K | ﹤0.01% |
11,600
+2,000
| +21% | +$14.2K |
|
5987
PUT
PetMed Express
PETS
$42.3M
| $81K | ﹤0.01% |
32,600
-1,500
| -4% | -$4.64K |
|
5988
CALL
PTC
PTC
$15.7B
| $81K | ﹤0.01% |
400
-6,900
| -95% | -$1.41M |
|
|
UROY
5989
PUT
Uranium Royalty Corp
UROY
$1.31B
| $81K | ﹤0.01% |
19,000
-30,000
| -61% | -$90.7K |
|
5990
CALL
Vir Biotechnology
VIR
$1.5B
| $81K | ﹤0.01% |
14,200
-6,700
| -32% | -$34.3K |
|
5991
PUT
Zai Lab
ZLAB
$2.06B
| $81K | ﹤0.01% |
2,400
+1,200
| +100% | +$41.3K |
|
5992
American Superconductor
AMSC
$1.47B
| $80K | ﹤0.01% |
1,363
-7,834
| -85% | -$392K |
|
5993
CALL
Aviat Networks
AVNW
$276M
| $80K | ﹤0.01% |
3,500
+1,800
| +106% | +$41.4K |
|
5994
PUT
Compass Minerals
CMP
$1.24B
| $80K | ﹤0.01% |
4,200
-7,300
| -63% | -$145K |
|
5995
Crinetics Pharmaceuticals
CRNX
$8.87B
| $80K | ﹤0.01% |
1,944
-3,397
| -64% | -$109K |
|
|
CVAC
5996
DELISTED
CureVac
CVAC
| $80K | ﹤0.01% |
14,903
-7,592
| -34% | -$41.1K |
|
|
GAMB
5997
PUT
DELISTED
Gambling.com
GAMB
| $80K | ﹤0.01% |
9,900
+5,800
| +141% | +$56.1K |
|
5998
CALL
Gevo
GEVO
$372M
| $80K | ﹤0.01% |
41,100
+6,600
| +19% | +$10.8K |
|
|
GOOD
5999
PUT
Gladstone Commercial Corp
GOOD
$606M
| $80K | ﹤0.01% |
6,500
+200
| +3% | +$2.67K |
|
6000
CALL
Holley
HLLY
$319M
| $80K | ﹤0.01% |
+25,500
| New | +$76K |
|
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.