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 | |
|---|---|---|---|---|---|---|
4026
Nuvation Bio
NUVB
$2.32B
| $427K | ﹤0.01% |
115,559
+77,905
| +207% | +$212K |
|
4027
PUT
Xylem
XYL
$28.8B
| $427K | ﹤0.01% |
2,900
-1,300
| -31% | -$180K |
|
|
SERV
4028
Serve Robotics
SERV
$396M
| $427K | ﹤0.01% |
36,765
+34,607
| +1,604% | +$379K |
|
4029
Ceragon Networks
CRNT
$195M
| $426K | ﹤0.01% |
183,106
-102,786
| -36% | -$227K |
|
|
NMAX
4030
CALL
Newsmax Inc
NMAX
$1.02B
| $426K | ﹤0.01% |
34,400
-31,200
| -48% | -$421K |
|
4031
CALL
CBRE Group
CBRE
$44.2B
| $425K | ﹤0.01% |
2,700
-1,800
| -40% | -$278K |
|
4032
Energizer
ENR
$1.48B
| $425K | ﹤0.01% |
17,095
+13,959
| +445% | +$365K |
|
4033
PUT
ING
ING
$93.9B
| $425K | ﹤0.01% |
16,300
-1,200
| -7% | -$28.9K |
|
4034
PUT
Target Hospitality
TH
$1.49B
| $425K | ﹤0.01% |
50,200
+40,700
| +428% | +$336K |
|
|
CHYM
4035
PUT
Chime Financial
CHYM
$8.6B
| $425K | ﹤0.01% |
21,100
+1,500
| +8% | +$42.6K |
|
4036
Brunswick
BC
$5.35B
| $424K | ﹤0.01% |
6,719
+2,008
| +43% | +$125K |
|
4037
CALL
Goldman Sachs Physical Gold ETF Shares
AAAU
$2.44B
| $423K | ﹤0.01% |
11,100
+10,900
| +5,450% | +$373K |
|
4038
PUT
Aurinia Pharmaceuticals
AUPH
$1.94B
| $423K | ﹤0.01% |
38,300
-80,100
| -68% | -$875K |
|
4039
CALL
Emergent Biosolutions
EBS
$375M
| $423K | ﹤0.01% |
48,000
-1,900
| -4% | -$14.8K |
|
4040
Green Dot
GDOT
$761M
| $423K | ﹤0.01% |
31,502
-17,903
| -36% | -$221K |
|
4041
CALL
ODDITY Tech
ODD
$770M
| $423K | ﹤0.01% |
6,800
-100
| -1% | -$6.5K |
|
4042
CALL
Patria Investments
PAX
$1.77B
| $423K | ﹤0.01% |
29,000
+6,800
| +31% | +$95K |
|
4043
CALL
Prime Medicine
PRME
$560M
| $423K | ﹤0.01% |
76,500
+33,600
| +78% | +$137K |
|
4044
PUT
Genesis Energy
GEL
$1.83B
| $422K | ﹤0.01% |
25,300
+4,500
| +22% | +$75.6K |
|
4045
CALL
Celldex Therapeutics
CLDX
$2.83B
| $421K | ﹤0.01% |
16,300
+11,500
| +240% | +$266K |
|
4046
Elastic
ESTC
$6.56B
| $421K | ﹤0.01% |
+4,984
| New | +$420K |
|
4047
PUT
NewAmsterdam Pharma
NAMS
$3.3B
| $420K | ﹤0.01% |
14,800
-1,700
| -10% | -$40.8K |
|
4048
PUT
OR Royalties Inc
OR
$5.47B
| $420K | ﹤0.01% |
+10,500
| New | +$328K |
|
4049
CALL
Paysign
PAYS
$514M
| $420K | ﹤0.01% |
66,800
+15,100
| +29% | +$96.5K |
|
4050
Qiagen
QGEN
$8.72B
| $420K | ﹤0.01% |
9,418
+41
| +0.4% | +$1.96K |
|
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.