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 | |
|---|---|---|---|---|---|---|
|
MTSR
3126
PUT
DELISTED
Metsera Inc
MTSR
| $936K | ﹤0.01% |
17,900
-15,900
| -47% | -$587K |
|
3127
PUT
Amer Sports
AS
$20.5B
| $934K | ﹤0.01% |
26,900
+1,800
| +7% | +$67.9K |
|
3128
PUT
MBIA
MBI
$282M
| $933K | ﹤0.01% |
+125,300
| New | +$794K |
|
3129
ProShares Ultra Bitcoin ETF
BITU
$362M
| $930K | ﹤0.01% |
17,429
+2,018
| +13% | +$113K |
|
3130
CALL
Inovio Pharmaceuticals
INO
$79.4M
| $929K | ﹤0.01% |
397,100
+202,500
| +104% | +$388K |
|
3131
CALL
Editas Medicine
EDIT
$411M
| $928K | ﹤0.01% |
267,700
+100,000
| +60% | +$279K |
|
3132
Cellebrite
CLBT
$3.65B
| $927K | ﹤0.01% |
50,061
+39,197
| +361% | +$616K |
|
3133
CALL
DT Midstream
DTM
$14.3B
| $927K | ﹤0.01% |
8,200
+8,000
| +4,000% | +$836K |
|
3134
PUT
TAL Education Group
TAL
$5.86B
| $926K | ﹤0.01% |
82,700
-210,800
| -72% | -$2.27M |
|
|
UNHG
3135
Leverage Shares 2X Long UNH Daily ETF
UNHG
$84.2M
| $924K | ﹤0.01% |
+43,595
| New | +$733K |
|
3136
PUT
Compass
COMP
$8.82B
| $923K | ﹤0.01% |
115,000
+92,800
| +418% | +$752K |
|
|
RAPP
3137
PUT
Rapport Therapeutics
RAPP
$2.01B
| $923K | ﹤0.01% |
+31,100
| New | +$555K |
|
3138
PUT
Banco Bilbao Vizcaya Argentaria
BBVA
$147B
| $922K | ﹤0.01% |
47,900
-24,600
| -34% | -$430K |
|
3139
CALL
InMode
INMD
$884M
| $922K | ﹤0.01% |
61,900
-8,600
| -12% | -$126K |
|
|
SEE
3140
CALL
DELISTED
Sealed Air
SEE
| $922K | ﹤0.01% |
26,100
+20,100
| +335% | +$641K |
|
3141
Biohaven
BHVN
$2.18B
| $920K | ﹤0.01% |
61,296
+11,814
| +24% | +$172K |
|
|
ONC
3142
PUT
BeOne Medicines Ltd
ONC
$33.8B
| $919K | ﹤0.01% |
2,700
+2,300
| +575% | +$698K |
|
3143
iShares US Aerospace & Defense ETF
ITA
$14.4B
| $918K | ﹤0.01% |
4,387
-5,127
| -54% | -$1.01M |
|
3144
Mattel
MAT
$4.3B
| $918K | ﹤0.01% |
54,586
+50,676
| +1,296% | +$924K |
|
3145
CALL
Acadia Healthcare
ACHC
$2.99B
| $916K | ﹤0.01% |
37,000
-89,600
| -71% | -$2M |
|
3146
CALL
The Ensign Group
ENSG
$10.4B
| $915K | ﹤0.01% |
5,300
+4,300
| +430% | +$686K |
|
3147
PUT
Invitation Homes
INVH
$17.6B
| $915K | ﹤0.01% |
31,200
+22,000
| +239% | +$678K |
|
3148
PUT
Microvast
MVST
$267M
| $915K | ﹤0.01% |
237,800
+71,900
| +43% | +$225K |
|
|
SPR
3149
CALL
DELISTED
Spirit AeroSystems
SPR
| $914K | ﹤0.01% |
23,700
-1,300
| -5% | -$52K |
|
|
CGC
3150
PUT
Canopy Growth
CGC
$390M
| $913K | ﹤0.01% |
625,900
+269,600
| +76% | +$350K |
|
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.