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 | |
|---|---|---|---|---|---|---|
1676
Pitney Bowes
PBI
$2.42B
| $4.01M | ﹤0.01% |
351,330
-1,797
| -0.5% | -$20.9K |
|
1677
PUT
Invesco CurrencyShares Euro Currency Trust
FXE
$331M
| $4M | ﹤0.01% |
36,900
+26,100
| +242% | +$2.81M |
|
1678
Chevron
CVX
$388B
| $3.99M | ﹤0.01% |
+25,676
| New | +$3.98M |
|
1679
CALL
Roivant Sciences
ROIV
$25.2B
| $3.98M | ﹤0.01% |
263,100
+59,100
| +29% | +$732K |
|
1680
PUT
L3Harris
LHX
$55.9B
| $3.97M | ﹤0.01% |
13,000
-4,400
| -25% | -$1.2M |
|
1681
uniQure
QURE
$2.68B
| $3.97M | ﹤0.01% |
67,995
+3,736
| +6% | +$67.8K |
|
1682
PUT
Ares Management
ARES
$28.5B
| $3.96M | ﹤0.01% |
24,800
-22,600
| -48% | -$4.08M |
|
1683
CALL
Hess Midstream
HESM
$5.22B
| $3.96M | ﹤0.01% |
114,500
+38,100
| +50% | +$1.51M |
|
1684
CALL
Lamb Weston
LW
$6.82B
| $3.96M | ﹤0.01% |
68,100
-54,500
| -44% | -$2.98M |
|
1685
PUT
KE Holdings
BEKE
$16.8B
| $3.95M | ﹤0.01% |
207,800
-185,100
| -47% | -$3.47M |
|
1686
CALL
FirstEnergy
FE
$28.9B
| $3.94M | ﹤0.01% |
86,000
-15,800
| -16% | -$675K |
|
1687
PUT
Amplify Online Retail ETF
IBUY
$106M
| $3.94M | ﹤0.01% |
160,500
-25,300
| -14% | -$1.85M |
|
1688
CALL
Indivior Pharmaceuticals
INDV
$4.79B
| $3.94M | ﹤0.01% |
163,300
+135,200
| +481% | +$2.83M |
|
1689
Harley-Davidson
HOG
$2.68B
| $3.92M | ﹤0.01% |
140,438
+49,758
| +55% | +$1.34M |
|
1690
PUT
TMC The Metals Company
TMC
$1.59B
| $3.91M | ﹤0.01% |
613,300
+27,700
| +5% | +$166K |
|
1691
PUT
Tetra Tech
TTEK
$8.23B
| $3.9M | ﹤0.01% |
117,000
+88,800
| +315% | +$3.23M |
|
1692
CALL
Nektar Therapeutics
NKTR
$2.39B
| $3.9M | ﹤0.01% |
68,600
-65,000
| -49% | -$2.15M |
|
1693
PUT
ARK 21Shares Bitcoin ETF
ARKB
$2.45B
| $3.9M | ﹤0.01% |
102,600
+3,700
| +4% | +$141K |
|
1694
CALL
Compass
COMP
$8.27B
| $3.9M | ﹤0.01% |
485,200
+168,900
| +53% | +$1.37M |
|
1695
CALL
Align Technology
ALGN
$12B
| $3.89M | ﹤0.01% |
31,100
+9,900
| +47% | +$1.55M |
|
1696
CALL
Dropbox
DBX
$6.81B
| $3.89M | ﹤0.01% |
128,900
+55,700
| +76% | +$1.59M |
|
1697
PUT
Levi Strauss
LEVI
$9.44B
| $3.88M | ﹤0.01% |
166,500
-72,100
| -30% | -$1.53M |
|
1698
Stellantis
STLA
$16.5B
| $3.88M | ﹤0.01% |
415,266
+320,677
| +339% | +$3.07M |
|
1699
PUT
Mirion Technologies
MIR
$4.05B
| $3.88M | ﹤0.01% |
166,700
-298,600
| -64% | -$6.45M |
|
1700
PUT
First Horizon
FHN
$12.1B
| $3.87M | ﹤0.01% |
171,300
+111,700
| +187% | +$2.48M |
|
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.