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 | |
|---|---|---|---|---|---|---|
3451
CALL
WEC Energy
WEC
$37.6B
| $687K | ﹤0.01% |
6,000
-4,000
| -40% | -$434K |
|
|
ILPT
3452
CALL
Industrial Logistics Properties Trust
ILPT
$605M
| $686K | ﹤0.01% |
117,700
+36,000
| +44% | +$207K |
|
3453
Fox Class A
FOXA
$24.4B
| $685K | ﹤0.01% |
10,866
+5,701
| +110% | +$330K |
|
3454
CALL
Grocery Outlet
GO
$937M
| $685K | ﹤0.01% |
42,700
-1,500
| -3% | -$24K |
|
|
VNET
3455
PUT
VNET Group
VNET
$1.9B
| $685K | ﹤0.01% |
66,400
-39,200
| -37% | -$330K |
|
3456
Chemours
CC
$2.54B
| $684K | ﹤0.01% |
43,219
+8,376
| +24% | +$121K |
|
3457
PUT
DoubleVerify
DV
$1.76B
| $684K | ﹤0.01% |
57,100
+45,300
| +384% | +$672K |
|
3458
Lightwave Logic
LWLG
$880M
| $684K | ﹤0.01% |
184,488
+163,652
| +785% | +$422K |
|
3459
Roivant Sciences
ROIV
$24.5B
| $684K | ﹤0.01% |
45,228
+1,972
| +5% | +$24.4K |
|
3460
PUT
Vital Farms
VITL
$590M
| $683K | ﹤0.01% |
16,600
-52,800
| -76% | -$2.29M |
|
3461
CALL
Adient
ADNT
$1.69B
| $681K | ﹤0.01% |
28,300
+20,100
| +245% | +$470K |
|
3462
CALL
Chegg
CHGG
$118M
| $679K | ﹤0.01% |
450,200
+100,000
| +29% | +$141K |
|
3463
Curtiss-Wright
CW
$26.6B
| $679K | ﹤0.01% |
1,252
-6,151
| -83% | -$3.03M |
|
3464
PUT
Owens Corning
OC
$11.7B
| $679K | ﹤0.01% |
4,800
-6,100
| -56% | -$895K |
|
3465
CALL
Old Republic International
ORI
$10.7B
| $679K | ﹤0.01% |
16,000
+6,500
| +68% | +$251K |
|
3466
PUT
Sterling Infrastructure
STRL
$16.8B
| $679K | ﹤0.01% |
2,000
-500
| -20% | -$142K |
|
3467
Fiverr
FVRR
$422M
| $678K | ﹤0.01% |
27,787
+23,202
| +506% | +$569K |
|
3468
CALL
Arcus Biosciences
RCUS
$3.36B
| $678K | ﹤0.01% |
49,900
-4,400
| -8% | -$45.8K |
|
3469
Offerpad Solutions
OPAD
$19.4M
| $677K | ﹤0.01% |
16,255
+15,917
| +4,709% | +$437K |
|
|
CHGX
3470
PUT
DELISTED
AXS Change Finance ESG ETF
CHGX
| $677K | ﹤0.01% |
74,500
+25,000
| +51% | +$227K |
|
3471
Array Technologies
ARRY
$789M
| $676K | ﹤0.01% |
82,974
+16,943
| +26% | +$128K |
|
3472
PUT
Crown Holdings
CCK
$13.1B
| $676K | ﹤0.01% |
7,000
+6,800
| +3,400% | +$682K |
|
3473
CALL
Extra Space Storage
EXR
$32.1B
| $676K | ﹤0.01% |
4,800
+1,900
| +66% | +$273K |
|
3474
PUT
Vanda Pharmaceuticals
VNDA
$310M
| $675K | ﹤0.01% |
135,300
-109,200
| -45% | -$506K |
|
3475
CALL
Mirum Pharmaceuticals
MIRM
$6.91B
| $674K | ﹤0.01% |
9,200
+6,300
| +217% | +$400K |
|
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.