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 | |
|---|---|---|---|---|---|---|
2951
Upwork
UPWK
$1.15B
| $1.12M | ﹤0.01% |
60,202
-8,397
| -12% | -$125K |
|
2952
CALL
Organon & Co
OGN
$3.56B
| $1.12M | ﹤0.01% |
104,500
-66,600
| -39% | -$654K |
|
2953
CALL
Globus Medical
GMED
$10.6B
| $1.11M | ﹤0.01% |
19,400
-7,500
| -28% | -$432K |
|
2954
PUT
VinFast Auto
VFS
$6.83B
| $1.11M | ﹤0.01% |
345,100
-21,800
| -6% | -$74.8K |
|
2955
PUT
Western Midstream Partners
WES
$19.3B
| $1.11M | ﹤0.01% |
28,300
-6,300
| -18% | -$246K |
|
2956
CALL
Banco Bradesco
BBD
$38.4B
| $1.11M | ﹤0.01% |
328,500
-269,700
| -45% | -$814K |
|
2957
CALL
Cerence
CRNC
$376M
| $1.11M | ﹤0.01% |
88,800
+10,500
| +13% | +$108K |
|
2958
Commault Systems
CVLT
$6.16B
| $1.1M | ﹤0.01% |
+5,843
| New | +$1.05M |
|
2959
CALL
ADT
ADT
$5.26B
| $1.1M | ﹤0.01% |
126,300
+124,900
| +8,921% | +$1.07M |
|
2960
VanEck Rare Earth/Strategic Metals ETF
REMX
$2.01B
| $1.1M | ﹤0.01% |
16,715
+14,570
| +679% | +$808K |
|
|
KLAR
2961
PUT
Klarna Group
KLAR
$6.93B
| $1.1M | ﹤0.01% |
+30,000
| New | +$1.28M |
|
2962
RH
RH
$3.4B
| $1.1M | ﹤0.01% |
+5,408
| New | +$1.17M |
|
|
SCHW
2963
Charles Schwab
SCHW
$180B
| $1.1M | ﹤0.01% |
+11,497
| New | +$1.09M |
|
2964
Crown Castle
CCI
$32.4B
| $1.09M | ﹤0.01% |
11,356
-79,264
| -87% | -$8.02M |
|
2965
PUT
Innovative Industrial Properties
IIPR
$1.79B
| $1.09M | ﹤0.01% |
20,400
+7,600
| +59% | +$413K |
|
2966
CALL
WillScot Mobile Mini Holdings
WSC
$4.79B
| $1.09M | ﹤0.01% |
51,800
-52,400
| -50% | -$1.35M |
|
2967
Lumentum
LITE
$54.9B
| $1.08M | ﹤0.01% |
6,670
-1,508
| -18% | -$188K |
|
|
OS
2968
PUT
DELISTED
OneStream Inc
OS
| $1.08M | ﹤0.01% |
58,900
+47,200
| +403% | +$1.04M |
|
2969
PUT
MediWound
MDWD
$189M
| $1.08M | ﹤0.01% |
60,100
+58,000
| +2,762% | +$1.07M |
|
2970
PUT
Rockwell Automation
ROK
$51.1B
| $1.08M | ﹤0.01% |
3,100
-1,200
| -28% | -$414K |
|
|
PENG
2971
PUT
Penguin Solutions Inc
PENG
$2.65B
| $1.08M | ﹤0.01% |
41,100
+39,600
| +2,640% | +$969K |
|
2972
Philips
PHG
$24.7B
| $1.08M | ﹤0.01% |
41,088
+6,250
| +18% | +$160K |
|
|
SAIL
2973
CALL
SailPoint Inc
SAIL
$8.91B
| $1.08M | ﹤0.01% |
48,900
+43,900
| +878% | +$919K |
|
2974
PUT
Syndax Pharmaceuticals
SNDX
$1.85B
| $1.08M | ﹤0.01% |
70,100
+35,700
| +104% | +$467K |
|
2975
CALL
Broadstone Net Lease
BNL
$4.35B
| $1.08M | ﹤0.01% |
60,300
+18,000
| +43% | +$310K |
|
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.