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 | |
|---|---|---|---|---|---|---|
1576
Wayfair
W
$11.1B
| $4.47M | ﹤0.01% |
+50,028
| New | +$3.66M |
|
1577
PUT
Genpact
G
$5.3B
| $4.46M | ﹤0.01% |
106,600
+103,900
| +3,848% | +$4.57M |
|
1578
PUT
Equinix
EQIX
$107B
| $4.46M | ﹤0.01% |
5,700
-2,200
| -28% | -$1.72M |
|
1579
PUT
Knight Transportation
KNX
$11.8B
| $4.46M | ﹤0.01% |
113,000
+19,500
| +21% | +$845K |
|
1580
Atlassian
TEAM
$22B
| $4.46M | ﹤0.01% |
+27,934
| New | +$5.05M |
|
1581
CALL
Vanguard FTSE Europe ETF
VGK
$30B
| $4.46M | ﹤0.01% |
60,600
-33,700
| -36% | -$2.64M |
|
1582
CALL
GlobalFoundries
GFS
$29.4B
| $4.45M | ﹤0.01% |
124,100
+92,800
| +296% | +$3.31M |
|
1583
PUT
Novavax
NVAX
$1.23B
| $4.44M | ﹤0.01% |
512,300
-114,000
| -18% | -$887K |
|
1584
CALL
Rush Street Interactive
RSI
$3.24B
| $4.44M | ﹤0.01% |
216,700
+78,200
| +56% | +$1.47M |
|
1585
CALL
Ecolab
ECL
$75.6B
| $4.44M | ﹤0.01% |
16,200
+10,400
| +179% | +$2.82M |
|
1586
EQT Corp
EQT
$33.2B
| $4.43M | ﹤0.01% |
81,422
+32,131
| +65% | +$1.7M |
|
1587
PUT
SLM Corp
SLM
$4.57B
| $4.43M | ﹤0.01% |
160,000
+34,000
| +27% | +$1.06M |
|
1588
CALL
Builders FirstSource
BLDR
$7.84B
| $4.42M | ﹤0.01% |
36,500
-6,200
| -15% | -$823K |
|
1589
CALL
Southern Copper
SCCO
$141B
| $4.42M | ﹤0.01% |
37,392
-69,171
| -65% | -$6.79M |
|
1590
CALL
Citizens Financial Group
CFG
$30.4B
| $4.41M | ﹤0.01% |
82,900
-107,200
| -56% | -$5.34M |
|
1591
PUT
IQVIA
IQV
$34.7B
| $4.41M | ﹤0.01% |
23,200
-20,200
| -47% | -$3.67M |
|
1592
CALL
FuelCell Energy
FCEL
$1.7B
| $4.4M | ﹤0.01% |
564,600
+50,600
| +10% | +$275K |
|
1593
PUT
Bank of Montreal
BMO
$125B
| $4.4M | ﹤0.01% |
33,800
+1,800
| +6% | +$213K |
|
1594
PUT
Gartner
IT
$9.41B
| $4.39M | ﹤0.01% |
16,700
+13,500
| +422% | +$3.94M |
|
1595
CALL
FTAI Aviation
FTAI
$22.2B
| $4.39M | ﹤0.01% |
26,300
-51,700
| -66% | -$7.35M |
|
1596
CALL
Canadian Solar
CSIQ
$906M
| $4.37M | ﹤0.01% |
335,000
+224,200
| +202% | +$2.68M |
|
|
TYNS
1597
PUT
DELISTED
Direxion Daily 7-10 Year Treasury Bear 1X Shares
TYNS
| $4.37M | ﹤0.01% |
25,300
-4,200
| -14% | -$725K |
|
1598
CALL
Amkor Technology
AMKR
$16.1B
| $4.37M | ﹤0.01% |
153,700
+95,700
| +165% | +$2.3M |
|
1599
CALL
Silicon Motion
SIMO
$9.19B
| $4.36M | ﹤0.01% |
46,000
+41,900
| +1,022% | +$3.33M |
|
1600
CALL
DigitalBridge
DBRG
$2.94B
| $4.36M | ﹤0.01% |
372,700
-161,200
| -30% | -$1.8M |
|
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.