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 | |
|---|---|---|---|---|---|---|
6551
CALL
Thomson Reuters
TRI
$46.4B
| $46K | ﹤0.01% |
295
-2,363
| -89% | -$441K |
|
6552
Valens Semiconductor
VLN
$160M
| $46K | ﹤0.01% |
25,761
+10,435
| +68% | +$23.6K |
|
6553
CALL
Vontier
VNT
$4.54B
| $46K | ﹤0.01% |
1,100
-2,300
| -68% | -$94.7K |
|
|
WSR
6554
CALL
DELISTED
Whitestone REIT
WSR
| $46K | ﹤0.01% |
3,800
+2,700
| +245% | +$34K |
|
|
INTW
6555
GraniteShares 2x Long INTC Daily ETF
INTW
$265M
| $46K | ﹤0.01% |
9,576
+6,472
| +209% | +$18K |
|
|
LABX
6556
Tradr 2X Long ALAB Daily ETF
LABX
$6.41M
| $46K | ﹤0.01% |
+3,404
| New | +$52.7K |
|
|
ABX
6557
PUT
Abacus Global Management
ABX
$988M
| $45K | ﹤0.01% |
7,900
-5,400
| -41% | -$32.1K |
|
6558
PUT
ANI Pharmaceuticals
ANIP
$1.86B
| $45K | ﹤0.01% |
500
-100
| -17% | -$8.15K |
|
6559
Arena Group
AREN
$55.2M
| $45K | ﹤0.01% |
8,232
+1,607
| +24% | +$10K |
|
6560
BARK
BARK
$77.9M
| $45K | ﹤0.01% |
2,757
+2,208
| +402% | +$39K |
|
6561
CALL
Cabot Corp
CBT
$4.72B
| $45K | ﹤0.01% |
600
+100
| +20% | +$7.8K |
|
6562
PUT
Carlyle Secured Lending
CGBD
$708M
| $45K | ﹤0.01% |
3,600
-2,400
| -40% | -$32.9K |
|
6563
CALL
Core Laboratories
CLB
$455M
| $45K | ﹤0.01% |
3,700
+2,500
| +208% | +$29.3K |
|
6564
PUT
Columbia Financial
CLBK
$1.14B
| $45K | ﹤0.01% |
3,000
+1,700
| +131% | +$25.3K |
|
6565
Clearfield
CLFD
$401M
| $45K | ﹤0.01% |
+1,327
| New | +$49.4K |
|
|
DSL
6566
PUT
DoubleLine Income Solutions Fund
DSL
$1.22B
| $45K | ﹤0.01% |
3,700
+1,500
| +68% | +$18.4K |
|
6567
Evolent Health
EVH
$371M
| $45K | ﹤0.01% |
5,417
-30,501
| -85% | -$296K |
|
6568
PUT
First Financial Bancorp
FFBC
$3.55B
| $45K | ﹤0.01% |
1,800
-3,600
| -67% | -$91.2K |
|
|
FFWM
6569
CALL
DELISTED
First Foundation Inc
FFWM
| $45K | ﹤0.01% |
8,100
-1,700
| -17% | -$9.38K |
|
6570
CALL
Grid Dynamics Holdings
GDYN
$569M
| $45K | ﹤0.01% |
5,900
+4,500
| +321% | +$40.2K |
|
|
GOOD
6571
Gladstone Commercial Corp
GOOD
$623M
| $45K | ﹤0.01% |
+3,696
| New | +$49.2K |
|
6572
PUT
NewtekOne
NEWT
$426M
| $45K | ﹤0.01% |
4,000
+3,900
| +3,900% | +$46.2K |
|
6573
CALL
Enpro
NPO
$6.26B
| $45K | ﹤0.01% |
200
-8,700
| -98% | -$1.88M |
|
6574
CALL
Playtika
PLTK
$1.53B
| $45K | ﹤0.01% |
11,700
+5,500
| +89% | +$22.4K |
|
6575
PUT
First Financial Corp
THFF
$948M
| $45K | ﹤0.01% |
+800
| New | +$45.3K |
|
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.