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 | |
|---|---|---|---|---|---|---|
1276
PUT
WIX.com
WIX
$2.15B
| $6.23M | ﹤0.01% |
35,100
+12,100
| +53% | +$1.82M |
|
1277
CALL
Advance Auto Parts
AAP
$3.37B
| $6.22M | ﹤0.01% |
101,400
-5,600
| -5% | -$331K |
|
1278
PUT
Logitech
LOGI
$15.2B
| $6.22M | ﹤0.01% |
56,700
+4,500
| +9% | +$452K |
|
1279
CALL
Simon Property Group
SPG
$74.5B
| $6.21M | ﹤0.01% |
33,100
-10,000
| -23% | -$1.73M |
|
1280
PUT
O'Reilly Automotive
ORLY
$72.4B
| $6.21M | ﹤0.01% |
57,600
-13,300
| -19% | -$1.34M |
|
1281
PUT
CRH
CRH
$66.7B
| $6.2M | ﹤0.01% |
51,700
+40,800
| +374% | +$4.31M |
|
|
CTRA
1282
CALL
DELISTED
Coterra Energy
CTRA
| $6.19M | ﹤0.01% |
261,900
+25,000
| +11% | +$603K |
|
1283
CALL
Alcoa
AA
$11.7B
| $6.16M | ﹤0.01% |
187,300
-2,200
| -1% | -$68.4K |
|
1284
CALL
dLocal
DLO
$4.26B
| $6.16M | ﹤0.01% |
431,100
+120,500
| +39% | +$1.53M |
|
1285
PUT
NetEase
NTES
$76.5B
| $6.16M | ﹤0.01% |
40,500
+15,500
| +62% | +$2.13M |
|
1286
PUT
Silicon Motion
SIMO
$9.19B
| $6.15M | ﹤0.01% |
64,900
+50,800
| +360% | +$4.04M |
|
|
SERV
1287
CALL
Serve Robotics
SERV
$409M
| $6.15M | ﹤0.01% |
528,500
+275,300
| +109% | +$3.02M |
|
1288
PUT
Scholar Rock
SRRK
$5.71B
| $6.14M | ﹤0.01% |
164,800
+136,200
| +476% | +$4.76M |
|
1289
PUT
Aon
AON
$77.3B
| $6.13M | ﹤0.01% |
17,200
+14,600
| +562% | +$5.28M |
|
1290
PUT
HEICO Corp Class A
HEI.A
$35.4B
| $6.13M | ﹤0.01% |
19,000
-1,800
| -9% | -$450K |
|
1291
PUT
Shake Shack
SHAK
$2.3B
| $6.12M | ﹤0.01% |
65,400
-37,600
| -37% | -$4.32M |
|
1292
PUT
United States Natural Gas Fund
UNG
$470M
| $6.12M | ﹤0.01% |
468,100
+55,700
| +14% | +$746K |
|
1293
PUT
Birkenstock
BIRK
$7.47B
| $6.11M | ﹤0.01% |
135,100
+24,000
| +22% | +$1.17M |
|
1294
PUT
Carbon Collective Climate Solutions US Equity ETF
CCSO
$45.3M
| $6.1M | ﹤0.01% |
467,100
-34,700
| -7% | -$827K |
|
1295
PUT
ReNew
RNW
$2.24B
| $6.09M | ﹤0.01% |
791,500
+638,800
| +418% | +$4.86M |
|
1296
PUT
KB Home
KBH
$3.48B
| $6.09M | ﹤0.01% |
95,700
+20,700
| +28% | +$1.25M |
|
1297
CALL
abrdn Physical Palladium Shares ETF
PALL
$603M
| $6.08M | ﹤0.01% |
266,500
+253,000
| +1,874% | +$5.42M |
|
1298
iShares US Home Construction ETF
ITB
$2.41B
| $6.08M | ﹤0.01% |
56,713
-78,006
| -58% | -$8.22M |
|
1299
PepsiCo
PEP
$186B
| $6.08M | ﹤0.01% |
43,304
-51,164
| -54% | -$7.31M |
|
1300
PUT
Zoetis
ZTS
$31.6B
| $6.07M | ﹤0.01% |
41,500
-45,100
| -52% | -$6.82M |
|
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.