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 | |
|---|---|---|---|---|---|---|
5551
CALL
Zebra Technologies
ZBRA
$14B
| $118K | ﹤0.01% |
400
-1,000
| -71% | -$319K |
|
|
KLC
5552
PUT
KinderCare Learning Companies
KLC
$634M
| $118K | ﹤0.01% |
17,800
-92,100
| -84% | -$773K |
|
5553
Archrock
AROC
$6.27B
| $117K | ﹤0.01% |
+4,481
| New | +$108K |
|
5554
PUT
Brookdale Senior Living
BKD
$3.49B
| $117K | ﹤0.01% |
13,900
-1,000
| -7% | -$7.62K |
|
5555
PUT
Beazer Homes USA
BZH
$877M
| $117K | ﹤0.01% |
4,800
-8,300
| -63% | -$204K |
|
5556
PUT
Enanta Pharmaceuticals
ENTA
$366M
| $117K | ﹤0.01% |
9,800
+8,800
| +880% | +$70.3K |
|
|
FINV
5557
CALL
FinVolution Group
FINV
$1.15B
| $117K | ﹤0.01% |
16,000
-300,800
| -95% | -$2.64M |
|
5558
Fulcrum Therapeutics
FULC
$273M
| $117K | ﹤0.01% |
12,800
-96,565
| -88% | -$699K |
|
5559
Jazz Pharmaceuticals
JAZZ
$15.9B
| $117K | ﹤0.01% |
891
+537
| +152% | +$64.4K |
|
5560
CALL
Mineralys Therapeutics
MLYS
$2.25B
| $117K | ﹤0.01% |
3,100
+2,200
| +244% | +$47.6K |
|
5561
VanEck Morningstar Wide Moat ETF
MOAT
$11.9B
| $117K | ﹤0.01% |
+1,189
| New | +$116K |
|
|
ORGN
5562
CALL
DELISTED
Origin Materials
ORGN
| $117K | ﹤0.01% |
7,570
-137
| -2% | -$2.54K |
|
5563
Sprott Gold Miners ETF
SGDM
$547M
| $117K | ﹤0.01% |
1,902
-558
| -23% | -$28.4K |
|
5564
PUT
Sagimet Biosciences
SGMT
$439M
| $117K | ﹤0.01% |
17,100
+1,300
| +8% | +$10.5K |
|
5565
Sky Harbour Group
SKYH
$369M
| $117K | ﹤0.01% |
11,923
+7,209
| +153% | +$73.6K |
|
5566
CALL
Teledyne Technologies
TDY
$30.4B
| $117K | ﹤0.01% |
200
-600
| -75% | -$328K |
|
|
5567
PUT
Teledyne Technologies
TDY
$30.4B
| $117K | ﹤0.01% |
+200
| New | +$109K |
|
5568
Wyndham Hotels & Resorts
WH
$5.56B
| $117K | ﹤0.01% |
+1,467
| New | +$126K |
|
|
LAR
5569
CALL
Lithium Argentina AG
LAR
$985M
| $117K | ﹤0.01% |
+35,200
| New | +$106K |
|
5570
CALL
AnaptysBio
ANAB
$1.58B
| $116K | ﹤0.01% |
3,800
-13,300
| -78% | -$305K |
|
5571
BBVA Argentina
BBAR
$3.87B
| $116K | ﹤0.01% |
14,047
+7,446
| +113% | +$101K |
|
5572
CALL
Brink's
BCO
$4.88B
| $116K | ﹤0.01% |
+1,000
| New | +$105K |
|
5573
iShares 25+ Year Treasury STRIPS Bond ETF
GOVZ
$256M
| $116K | ﹤0.01% |
2,998
+2,328
| +347% | +$87.6K |
|
5574
PUT
Larimar Therapeutics
LRMR
$397M
| $116K | ﹤0.01% |
36,200
+3,000
| +9% | +$11.2K |
|
5575
PUT
RxSight
RXST
$249M
| $116K | ﹤0.01% |
13,000
+10,400
| +400% | +$91.3K |
|
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.