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 | |
|---|---|---|---|---|---|---|
2851
CALL
Legend Biotech
LEGN
$3.64B
| $1.21M | ﹤0.01% |
37,200
-11,000
| -23% | -$406K |
|
2852
PUT
MannKind Corp
MNKD
$1.26B
| $1.21M | ﹤0.01% |
226,000
+139,700
| +162% | +$613K |
|
|
ARR
2853
CALL
Armour Residential REIT
ARR
$2.02B
| $1.21M | ﹤0.01% |
81,100
+20,000
| +33% | +$314K |
|
|
TGNA
2854
DELISTED
TEGNA Inc
TGNA
| $1.21M | ﹤0.01% |
59,559
+47,176
| +381% | +$899K |
|
2855
PUT
Upwork
UPWK
$1.16B
| $1.21M | ﹤0.01% |
65,200
-29,200
| -31% | -$435K |
|
2856
ZTO Express
ZTO
$18.2B
| $1.21M | ﹤0.01% |
+63,018
| New | +$1.21M |
|
|
SMU
2857
PUT
Tradr 2X Long SMR Daily ETF
SMU
$46.4M
| $1.21M | ﹤0.01% |
+3,487
| New | +$1.51M |
|
2858
CALL
Cooper-Standard Automotive
CPS
$501M
| $1.21M | ﹤0.01% |
32,700
+23,400
| +252% | +$713K |
|
|
CMBT
2859
CMB.TECH NV
CMBT
$4.48B
| $1.21M | ﹤0.01% |
+128,479
| New | +$1.18M |
|
2860
PUT
Reservoir Media
RSVR
$702M
| $1.21M | ﹤0.01% |
148,100
+114,300
| +338% | +$893K |
|
2861
CALL
American Century Diversified Corporate Bond ETF
KORP
$871M
| $1.2M | ﹤0.01% |
12,100
+8,800
| +267% | +$415K |
|
2862
CarMax
KMX
$8.24B
| $1.2M | ﹤0.01% |
26,706
+24,623
| +1,182% | +$1.47M |
|
2863
CALL
Ramaco Resources Class A
METC
$659M
| $1.2M | ﹤0.01% |
36,100
-21,600
| -37% | -$502K |
|
|
TIC
2864
TIC Solutions Inc
TIC
$1.59B
| $1.2M | ﹤0.01% |
+90,061
| New | +$1.03M |
|
2865
PUT
Dave Inc
DAVE
$5.12B
| $1.2M | ﹤0.01% |
6,000
+3,700
| +161% | +$799K |
|
2866
PUT
Ollie's Bargain Outlet
OLLI
$4.06B
| $1.19M | ﹤0.01% |
9,300
-3,500
| -27% | -$465K |
|
2867
Praxis Precision Medicines
PRAX
$8.98B
| $1.19M | ﹤0.01% |
22,529
-2,799
| -11% | -$136K |
|
2868
CALL
Parsons
PSN
$6.33B
| $1.19M | ﹤0.01% |
14,400
-14,200
| -50% | -$1.1M |
|
2869
PUT
Agilent Technologies
A
$38.8B
| $1.19M | ﹤0.01% |
9,300
+700
| +8% | +$84.5K |
|
2870
Etsy
ETSY
$7.85B
| $1.19M | ﹤0.01% |
+17,958
| New | +$1.07M |
|
|
NAKA
2871
PUT
Nakamoto Inc
NAKA
$79.9M
| $1.19M | ﹤0.01% |
+27,815
| New | +$8.82M |
|
2872
PUT
Landstar System
LSTR
$6.5B
| $1.19M | ﹤0.01% |
9,700
+1,100
| +13% | +$146K |
|
2873
PUT
Casey's General Stores
CASY
$31.9B
| $1.19M | ﹤0.01% |
2,100
+500
| +31% | +$262K |
|
2874
Hormel Foods
HRL
$14.2B
| $1.19M | ﹤0.01% |
48,002
+41,972
| +696% | +$1.16M |
|
2875
PUT
Portillo's
PTLO
$335M
| $1.19M | ﹤0.01% |
184,100
+65,900
| +56% | +$556K |
|
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.