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 | |
|---|---|---|---|---|---|---|
6701
Personalis
PSNL
$1.25B
| $39K | ﹤0.01% |
+6,076
| New | +$34.6K |
|
6702
CALL
RBC Bearings
RBC
$17.4B
| $39K | ﹤0.01% |
100
-400
| -80% | -$156K |
|
6703
PUT
Arcus Biosciences
RCUS
$3.33B
| $39K | ﹤0.01% |
2,900
-3,300
| -53% | -$34.3K |
|
6704
Revvity
RVTY
$12.6B
| $39K | ﹤0.01% |
+447
| New | +$40.6K |
|
6705
PUT
Saic
SAIC
$4.95B
| $39K | ﹤0.01% |
400
-100
| -20% | -$11.2K |
|
|
VBNK
6706
CALL
VersaBank
VBNK
$623M
| $39K | ﹤0.01% |
3,200
+2,900
| +967% | +$33.5K |
|
6707
CALL
Veeco
VECO
$2.62B
| $39K | ﹤0.01% |
1,300
-40,500
| -97% | -$965K |
|
|
VZLA
6708
Vizsla Silver
VZLA
$1.1B
| $39K | ﹤0.01% |
+9,227
| New | +$32K |
|
6709
PUT
Westlake Chemical Partners
WLKP
$772M
| $39K | ﹤0.01% |
1,900
+800
| +73% | +$17.5K |
|
|
SMC
6710
Summit Midstream
SMC
$420M
| $39K | ﹤0.01% |
+1,908
| New | +$44.3K |
|
|
STKE
6711
CALL
Sol Strategies Inc
STKE
$38.8M
| $39K | ﹤0.01% |
+9,000
| New | +$54.5K |
|
6712
CALL
Alto Ingredients
ALTO
$338M
| $38K | ﹤0.01% |
36,100
+3,800
| +12% | +$4.27K |
|
6713
PUT
Annovis Bio
ANVS
$72.3M
| $38K | ﹤0.01% |
18,500
-5,600
| -23% | -$14K |
|
6714
PUT
AvalonBay Communities
AVB
$27.5B
| $38K | ﹤0.01% |
200
| – | – |
|
6715
PUT
Butterfly Network
BFLY
$1.86B
| $38K | ﹤0.01% |
20,100
-28,300
| -58% | -$48.1K |
|
6716
Carriage Services
CSV
$647M
| $38K | ﹤0.01% |
866
-660
| -43% | -$29.8K |
|
6717
PUT
CytomX Therapeutics
CTMX
$690M
| $38K | ﹤0.01% |
12,200
-16,600
| -58% | -$37.4K |
|
6718
PUT
Covenant Logistics
CVLG
$1.04B
| $38K | ﹤0.01% |
1,800
-8,300
| -82% | -$198K |
|
6719
CALL
Cushman & Wakefield Ltd
CWK
$3.16B
| $38K | ﹤0.01% |
2,400
-1,500
| -38% | -$21.1K |
|
6720
PUT
Ducommun
DCO
$2.56B
| $38K | ﹤0.01% |
400
+300
| +300% | +$27.1K |
|
|
EHAB
6721
DELISTED
Enhabit
EHAB
| $38K | ﹤0.01% |
4,779
+4,169
| +683% | +$31.3K |
|
6722
CALL
Gladstone Investment Corp
GAIN
$642M
| $38K | ﹤0.01% |
2,800
+500
| +22% | +$7.04K |
|
6723
PUT
Horizon Bancorp
HBNC
$1.06B
| $38K | ﹤0.01% |
+2,400
| New | +$38.4K |
|
6724
PUT
Humacyte
HUMA
$168M
| $38K | ﹤0.01% |
22,200
-10,700
| -33% | -$21K |
|
6725
Karyopharm Therapeutics
KPTI
$155M
| $38K | ﹤0.01% |
5,862
-2,371
| -29% | -$12.8K |
|
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.