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 | |
|---|---|---|---|---|---|---|
4176
CALL
STAG Industrial
STAG
$7.44B
| $377K | ﹤0.01% |
10,700
+1,000
| +10% | +$35.7K |
|
4177
Bumble
BMBL
$387M
| $376K | ﹤0.01% |
61,824
-177,022
| -74% | -$1.21M |
|
4178
Fidelity National Financial
FNF
$14.4B
| $376K | ﹤0.01% |
6,217
+3,973
| +177% | +$231K |
|
4179
CALL
Pentair
PNR
$10.8B
| $376K | ﹤0.01% |
3,400
-3,000
| -47% | -$320K |
|
4180
Companhia Siderúrgica Nacional
SID
$1.37B
| $376K | ﹤0.01% |
251,262
+1,897
| +0.8% | +$2.73K |
|
4181
Voya Financial
VOYA
$8.96B
| $376K | ﹤0.01% |
+5,031
| New | +$371K |
|
4182
WillScot Mobile Mini Holdings
WSC
$4.37B
| $376K | ﹤0.01% |
17,838
+11,303
| +173% | +$291K |
|
4183
CALL
FLEX LNG
FLNG
$1.69B
| $375K | ﹤0.01% |
14,900
-10,300
| -41% | -$255K |
|
|
NB
4184
PUT
NioCorp Developments
NB
$562M
| $375K | ﹤0.01% |
56,200
-1,900
| -3% | -$8.02K |
|
4185
PUT
Omnicom Group
OMC
$23.5B
| $375K | ﹤0.01% |
4,600
-50,700
| -92% | -$3.83M |
|
4186
CALL
Solid Power
SLDP
$450M
| $375K | ﹤0.01% |
108,200
+88,200
| +441% | +$332K |
|
4187
Telephone and Data Systems
TDS
$3.87B
| $375K | ﹤0.01% |
9,569
-20,280
| -68% | -$780K |
|
4188
Target Hospitality
TH
$1.43B
| $375K | ﹤0.01% |
44,317
+39,842
| +890% | +$328K |
|
4189
CALL
United Microelectronic
UMC
$42.9B
| $375K | ﹤0.01% |
49,600
+12,200
| +33% | +$86.5K |
|
4190
CALL
WPP
WPP
$4.67B
| $375K | ﹤0.01% |
+15,000
| New | +$410K |
|
4191
CALL
Bank of Hawaii
BOH
$3.14B
| $374K | ﹤0.01% |
5,700
+5,200
| +1,040% | +$347K |
|
4192
CorMedix
CRMD
$564M
| $374K | ﹤0.01% |
+32,232
| New | +$390K |
|
4193
PUT
Federal Realty Investment Trust
FRT
$10.9B
| $374K | ﹤0.01% |
3,700
+100
| +3% | +$9.66K |
|
4194
PUT
Remitly
RELY
$4.9B
| $374K | ﹤0.01% |
23,000
-67,500
| -75% | -$1.21M |
|
4195
ProShares Ultra VIX Short-Term Futures ETF
UVXY
$259M
| $374K | ﹤0.01% |
+7,170
| New | +$499K |
|
4196
CALL
Vuzix
VUZI
$178M
| $374K | ﹤0.01% |
119,600
-7,400
| -6% | -$17.5K |
|
4197
CALL
Vanguard Total International Stock ETF
VXUS
$151B
| $374K | ﹤0.01% |
5,100
-1,100
| -18% | -$78.1K |
|
|
DVAX
4198
CALL
DELISTED
Dynavax Technologies
DVAX
| $373K | ﹤0.01% |
37,600
+9,900
| +36% | +$103K |
|
4199
iShares US Oil & Gas Exploration & Production ETF
IEO
$566M
| $373K | ﹤0.01% |
4,029
+3,904
| +3,123% | +$354K |
|
4200
CALL
Lightspeed Commerce
LSPD
$1.44B
| $373K | ﹤0.01% |
32,300
+20,200
| +167% | +$247K |
|
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.