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 |
Netflix
NFLX
|
+$73.1M |
| 2 |
Western Digital
WDC
|
+$51.8M |
| 3 |
iShares Semiconductor ETF
SOXX
|
+$46M |
| 4 |
Meta Platforms (Facebook)
META
|
+$41.8M |
| 5 |
Alibaba
BABA
|
+$37.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
NVIDIA
NVDA
|
+$262M |
| 2 |
Microsoft
MSFT
|
+$194M |
| 3 |
iShares Russell 2000 ETF
IWM
|
+$149M |
| 4 |
Apple
AAPL
|
+$119M |
| 5 |
Amazon
AMZN
|
+$107M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.59% |
| 2 | Consumer Discretionary | 0.21% |
| 3 | Healthcare | 0.2% |
| 4 | Industrials | 0.18% |
| 5 | Communication Services | 0.16% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
1551
PUT
Zimmer Biomet
ZBH
$17.7B
| $3.47M | ﹤0.01% |
38,600
+2,300
| +6% | +$218K |
|
1552
CALL
Aptiv
APTV
$12B
| $3.47M | ﹤0.01% |
45,600
-1,800
| -4% | -$145K |
|
1553
CALL
Bath & Body Works
BBWI
$4.01B
| $3.47M | ﹤0.01% |
172,600
+30,900
| +22% | +$682K |
|
1554
Sibanye-Stillwater
SBSW
$5.92B
| $3.46M | ﹤0.01% |
242,803
+133,865
| +123% | +$1.62M |
|
1555
PUT
Xcel Energy
XEL
$51B
| $3.46M | ﹤0.01% |
46,800
+7,100
| +18% | +$560K |
|
1556
CALL
Blackstone Secured Lending
BXSL
$5.41B
| $3.45M | ﹤0.01% |
131,000
+89,700
| +217% | +$2.41M |
|
1557
Forward Air
FWRD
$482M
| $3.44M | ﹤0.01% |
137,530
+73,612
| +115% | +$1.66M |
|
1558
CALL
Zions Bancorporation
ZION
$10.1B
| $3.44M | ﹤0.01% |
58,700
+19,600
| +50% | +$1.07M |
|
1559
PUT
Cheesecake Factory
CAKE
$4.21B
| $3.43M | ﹤0.01% |
67,900
+42,800
| +171% | +$2.15M |
|
1560
CALL
Starwood Property Trust
STWD
$6.12B
| $3.43M | ﹤0.01% |
190,300
-86,900
| -31% | -$1.6M |
|
1561
CALL
Dick's Sporting Goods
DKS
$18.4B
| $3.42M | ﹤0.01% |
17,300
-38,500
| -69% | -$8.4M |
|
1562
PUT
Fiverr
FVRR
$376M
| $3.42M | ﹤0.01% |
173,100
+130,500
| +306% | +$2.81M |
|
1563
CALL
Franco-Nevada
FNV
$41.4B
| $3.42M | ﹤0.01% |
16,500
-65,500
| -80% | -$13.3M |
|
|
TE
1564
CALL
T1 Energy
TE
$1.4B
| $3.41M | ﹤0.01% |
510,300
+401,300
| +368% | +$1.77M |
|
1565
PUT
Pool Corp
POOL
$6.7B
| $3.41M | ﹤0.01% |
14,900
+12,500
| +521% | +$3.25M |
|
|
VG
1566
PUT
Venture Global Inc
VG
$35.6B
| $3.41M | ﹤0.01% |
499,600
+341,800
| +217% | +$2.85M |
|
1567
Costco
COST
$415B
| $3.41M | ﹤0.01% |
+3,949
| New | +$3.58M |
|
1568
PUT
HF Sinclair
DINO
$15.9B
| $3.41M | ﹤0.01% |
73,900
+15,000
| +25% | +$773K |
|
1569
CALL
Infosys
INFY
$45B
| $3.39M | ﹤0.01% |
190,300
-121,300
| -39% | -$2.1M |
|
1570
PUT
Natera
NTRA
$37.5B
| $3.39M | ﹤0.01% |
14,800
-2,600
| -15% | -$542K |
|
|
JBTM
1571
CALL
JBT Marel
JBTM
$7.14B
| $3.39M | ﹤0.01% |
22,500
+20,100
| +838% | +$2.83M |
|
1572
CALL
Century Aluminum
CENX
$4.57B
| $3.38M | ﹤0.01% |
86,200
-5,500
| -6% | -$172K |
|
1573
CALL
Mirion Technologies
MIR
$4.05B
| $3.37M | ﹤0.01% |
144,000
+45,800
| +47% | +$1.14M |
|
|
ETHA
1574
iShares Ethereum Trust ETF
ETHA
$5.25B
| $3.37M | ﹤0.01% |
150,038
-373,355
| -71% | -$9.76M |
|
1575
CALL
Avery Dennison
AVY
$12.3B
| $3.36M | ﹤0.01% |
18,500
| – | – |
|
Similar funds
Simplex Trading's Q4 2025 Portfolio in Review
As of Q4 2025, Simplex Trading held 10,526 positions worth $177B, down 9% from $195B the previous quarter. Its ten largest holdings account for 49% of the portfolio.
Simplex Trading withdrew a net $23.2B in Q4 2025, closing 2,184 positions and reducing 4,088 holdings. Its most notable exit was iShares Russell 2000 ETF, an estimated $149M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.59% of assets, down from 0.79% a quarter earlier, followed by Consumer Discretionary and Healthcare.
Against the trend, Simplex Trading opened a new position in Western Digital worth $58.9M.
- Simplex Trading's largest Q4 2025 buy was Western Digital: 341,762 shares worth $58.9M.
- Simplex Trading added most to Netflix in Q4 2025, an estimated $73.1M increase.
- Simplex Trading's biggest Q4 2025 reduction was NVIDIA, cutting an estimated $262M.
- Simplex Trading fully exited iShares Russell 2000 ETF in Q4 2025, selling an estimated $149M.
- Simplex Trading's ten largest holdings make up 49% of its $177B portfolio in Q4 2025.
- Simplex Trading opened 1,476 new positions and closed 2,184 in Q4 2025.
- Simplex Trading's portfolio value fell 9% quarter-over-quarter to $177B.
Based on Simplex Trading's 13F filing for Q4 2025, filed 11 Feb 2026.