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 | |
|---|---|---|---|---|---|---|
1201
Energy Fuels
UUUU
$2.9B
| $6.88M | ﹤0.01% |
447,925
-29,651
| -6% | -$315K |
|
1202
PUT
Builders FirstSource
BLDR
$7.92B
| $6.87M | ﹤0.01% |
56,700
-33,300
| -37% | -$4.42M |
|
1203
CALL
IAMGOLD
IAG
$8.61B
| $6.86M | ﹤0.01% |
530,700
+183,700
| +53% | +$1.61M |
|
1204
CALL
Ascendis Pharma A/S
ASND
$16.9B
| $6.86M | ﹤0.01% |
34,500
+23,400
| +211% | +$4.36M |
|
|
DFDV
1205
PUT
DeFi Development Corp
DFDV
$83.7M
| $6.86M | ﹤0.01% |
492,580
+467,830
| +1,890% | +$7.77M |
|
1206
CALL
Telephone and Data Systems
TDS
$3.94B
| $6.85M | ﹤0.01% |
174,600
-1,700
| -1% | -$65.4K |
|
1207
PUT
Whirlpool
WHR
$2.4B
| $6.85M | ﹤0.01% |
87,100
+8,600
| +11% | +$789K |
|
1208
CALL
Ross Stores
ROST
$76.3B
| $6.84M | ﹤0.01% |
44,900
-80,600
| -64% | -$11.5M |
|
1209
PUT
Cardinal Health
CAH
$53.6B
| $6.83M | ﹤0.01% |
43,500
+4,000
| +10% | +$618K |
|
1210
Crocs
CROX
$6.74B
| $6.83M | ﹤0.01% |
81,696
+73,478
| +894% | +$6.71M |
|
1211
PUT
TTM Technologies
TTMI
$14.3B
| $6.82M | ﹤0.01% |
118,400
+117,800
| +19,633% | +$5.47M |
|
1212
CALL
SL Green Realty
SLG
$3.9B
| $6.82M | ﹤0.01% |
114,000
+39,100
| +52% | +$2.31M |
|
1213
PUT
Sibanye-Stillwater
SBSW
$6.04B
| $6.81M | ﹤0.01% |
605,900
+98,800
| +19% | +$863K |
|
1214
PUT
Suncor Energy
SU
$77.8B
| $6.8M | ﹤0.01% |
162,600
-252,700
| -61% | -$10.1M |
|
1215
PUT
American Eagle Outfitters
AEO
$2.89B
| $6.79M | ﹤0.01% |
396,900
+228,500
| +136% | +$3.13M |
|
1216
CALL
argenx
ARGX
$57.6B
| $6.79M | ﹤0.01% |
9,200
-4,700
| -34% | -$3.1M |
|
1217
PUT
HubSpot
HUBS
$10.3B
| $6.78M | ﹤0.01% |
14,500
-1,700
| -10% | -$855K |
|
1218
CALL
Transocean
RIG
$5.93B
| $6.78M | ﹤0.01% |
2,174,000
+632,800
| +41% | +$1.91M |
|
1219
Rigetti Computing
RGTI
$4.87B
| $6.78M | ﹤0.01% |
+227,434
| New | +$3.99M |
|
|
TLN
1220
PUT
Talen Energy Corp
TLN
$17.8B
| $6.76M | ﹤0.01% |
15,900
-8,100
| -34% | -$2.93M |
|
1221
PUT
Unilever
UL
$131B
| $6.75M | ﹤0.01% |
101,244
-26,489
| -21% | -$1.83M |
|
1222
Li Auto
LI
$12.7B
| $6.75M | ﹤0.01% |
266,263
+249,840
| +1,521% | +$6.47M |
|
1223
PUT
Johnson Controls International
JCI
$87.9B
| $6.72M | ﹤0.01% |
61,100
-136,200
| -69% | -$14.6M |
|
1224
CALL
Axsome Therapeutics
AXSM
$12.4B
| $6.72M | ﹤0.01% |
55,300
+6,000
| +12% | +$676K |
|
1225
CALL
AeroVironment
AVAV
$7.76B
| $6.71M | ﹤0.01% |
21,300
+2,000
| +10% | +$517K |
|
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.