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 | |
|---|---|---|---|---|---|---|
4426
CALL
Global Ship Lease
GSL
$1.56B
| $307K | ﹤0.01% |
10,000
-32,100
| -76% | -$956K |
|
4427
CALL
Ryanair
RYAAY
$30B
| $307K | ﹤0.01% |
5,100
-4,300
| -46% | -$262K |
|
4428
Genesis Energy
GEL
$1.82B
| $306K | ﹤0.01% |
+18,327
| New | +$308K |
|
|
XRN
4429
CALL
Chiron Real Estate Inc
XRN
$535M
| $306K | ﹤0.01% |
9,100
+8,940
| +5,588% | +$318K |
|
4430
PUT
Open Text
OTEX
$6.28B
| $306K | ﹤0.01% |
8,200
+400
| +5% | +$12.8K |
|
4431
Schrodinger
SDGR
$1.13B
| $306K | ﹤0.01% |
15,262
+9,668
| +173% | +$194K |
|
4432
CALL
Arteris
AIP
$1.24B
| $305K | ﹤0.01% |
30,200
-5,200
| -15% | -$49.5K |
|
4433
YieldMax COIN Option Income Strategy ETF
CONY
$344M
| $305K | ﹤0.01% |
4,437
+3,765
| +560% | +$296K |
|
4434
CALL
Prudential
PUK
$36.4B
| $305K | ﹤0.01% |
10,900
+900
| +9% | +$23.6K |
|
4435
CALL
Surgery Partners
SGRY
$2.15B
| $305K | ﹤0.01% |
14,100
-23,300
| -62% | -$520K |
|
|
AIRO
4436
PUT
AIRO Group Holdings
AIRO
$197M
| $305K | ﹤0.01% |
+15,900
| New | +$349K |
|
4437
ACV Auctions
ACVA
$1.41B
| $304K | ﹤0.01% |
+30,697
| New | +$393K |
|
4438
PUT
Element Solutions
ESI
$8.48B
| $304K | ﹤0.01% |
12,100
+5,100
| +73% | +$127K |
|
4439
CALL
Gold Royalty Corp
GROY
$602M
| $304K | ﹤0.01% |
79,000
-31,400
| -28% | -$97K |
|
|
4440
PUT
Gold Royalty Corp
GROY
$602M
| $304K | ﹤0.01% |
78,900
+65,800
| +502% | +$203K |
|
4441
PUT
News Corp Class B
NWS
$17.7B
| $304K | ﹤0.01% |
9,900
-7,200
| -42% | -$243K |
|
4442
SiTime
SITM
$13.8B
| $304K | ﹤0.01% |
1,012
+770
| +318% | +$178K |
|
|
SKE
4443
Skeena Resources
SKE
$3.19B
| $304K | ﹤0.01% |
+16,517
| New | +$270K |
|
4444
PUT
Vanguard S&P 500 Growth ETF
VOOG
$24.7B
| $304K | ﹤0.01% |
4,200
+600
| +17% | +$41.5K |
|
4445
Solid Power
SLDP
$450M
| $303K | ﹤0.01% |
87,608
-3,522
| -4% | -$13.3K |
|
4446
CALL
Atomera
ATOM
$173M
| $302K | ﹤0.01% |
68,400
-37,900
| -36% | -$156K |
|
4447
PUT
CVR Energy
CVI
$3.48B
| $302K | ﹤0.01% |
8,300
-28,300
| -77% | -$847K |
|
|
SFIX
4448
CALL
Stitch Fix
SFIX
$567M
| $302K | ﹤0.01% |
69,600
+11,000
| +19% | +$54.3K |
|
4449
CALL
Atkore
ATKR
$2.41B
| $301K | ﹤0.01% |
4,800
+700
| +17% | +$45.6K |
|
4450
CALL
Black Hills Corp
BKH
$5.55B
| $301K | ﹤0.01% |
4,900
+4,000
| +444% | +$235K |
|
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.