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 | |
|---|---|---|---|---|---|---|
|
MRX
3226
CALL
Marex Group Limited Ordinary Shares
MRX
$4.65B
| $843K | ﹤0.01% |
25,100
+16,400
| +189% | +$592K |
|
3227
BCE
BCE
$19.8B
| $842K | ﹤0.01% |
+36,016
| New | +$868K |
|
3228
CALL
Commercial Metals
CMC
$7.53B
| $842K | ﹤0.01% |
14,700
-22,400
| -60% | -$1.24M |
|
3229
National Grid
NGG
$81.6B
| $842K | ﹤0.01% |
11,759
+9,672
| +463% | +$678K |
|
3230
Vanguard Long-Term Treasury ETF
VGLT
$10.2B
| $842K | ﹤0.01% |
14,813
-23,024
| -61% | -$1.28M |
|
3231
CALL
PBF Energy
PBF
$7.43B
| $841K | ﹤0.01% |
27,900
-170,100
| -86% | -$4.45M |
|
3232
Labcorp
LH
$24.7B
| $840K | ﹤0.01% |
2,928
-878
| -23% | -$235K |
|
3233
Comfort Systems
FIX
$60.9B
| $839K | ﹤0.01% |
1,017
+431
| +74% | +$292K |
|
3234
PUT
Solid Power
SLDP
$481M
| $839K | ﹤0.01% |
241,800
+235,700
| +3,864% | +$888K |
|
3235
CALL
Fomento Económico Mexicano
FMX
$45B
| $838K | ﹤0.01% |
+8,500
| New | +$790K |
|
|
PBT
3236
Permian Basin Royalty Trust
PBT
$1.29B
| $838K | ﹤0.01% |
45,919
+35,535
| +342% | +$554K |
|
3237
CALL
Western Union
WU
$2.55B
| $838K | ﹤0.01% |
105,000
-78,000
| -43% | -$652K |
|
3238
Vanguard Growth ETF
VUG
$216B
| $837K | ﹤0.01% |
+10,476
| New | +$801K |
|
3239
CALL
Axogen
AXGN
$2.19B
| $836K | ﹤0.01% |
46,900
+46,700
| +23,350% | +$678K |
|
|
PBT
3240
PUT
Permian Basin Royalty Trust
PBT
$1.29B
| $835K | ﹤0.01% |
45,800
+19,600
| +75% | +$305K |
|
3241
CALL
nLIGHT
LASR
$3.82B
| $832K | ﹤0.01% |
28,100
+22,700
| +420% | +$563K |
|
3242
FerroAtlántica
GSM
$617M
| $831K | ﹤0.01% |
+182,772
| New | +$782K |
|
|
OBE
3243
CALL
Obsidian Energy
OBE
$660M
| $831K | ﹤0.01% |
127,100
+92,000
| +262% | +$547K |
|
3244
CALL
Qorvo
QRVO
$7.92B
| $828K | ﹤0.01% |
9,100
-20,700
| -69% | -$1.84M |
|
3245
PUT
US Foods
USFD
$21.9B
| $827K | ﹤0.01% |
10,800
+8,000
| +286% | +$636K |
|
3246
PUT
Dentsply Sirona
XRAY
$2.61B
| $827K | ﹤0.01% |
65,200
+63,800
| +4,557% | +$926K |
|
3247
CALL
IMAX
IMAX
$2.47B
| $825K | ﹤0.01% |
25,200
+24,300
| +2,700% | +$689K |
|
|
EU
3248
enCore Energy
EU
$231M
| $824K | ﹤0.01% |
256,913
+167,203
| +186% | +$450K |
|
3249
TAL Education Group
TAL
$5.86B
| $824K | ﹤0.01% |
73,607
+11,954
| +19% | +$129K |
|
3250
PUT
Geospace Technologies
GEOS
$90M
| $822K | ﹤0.01% |
43,400
+36,000
| +486% | +$583K |
|
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.