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 | |
|---|---|---|---|---|---|---|
|
OKLL
3626
Defiance Daily Target 2x Long OKLO ETF
OKLL
$129M
| $362K | ﹤0.01% |
+21,586
| New | +$1.18M |
|
3627
Indivior Pharmaceuticals
INDV
$4.85B
| $362K | ﹤0.01% |
+10,085
| New | +$308K |
|
|
ORBS
3628
CALL
Eightco Holdings
ORBS
$232M
| $361K | ﹤0.01% |
+208,700
| New | +$980K |
|
3629
CALL
IQVIA
IQV
$40.5B
| $361K | ﹤0.01% |
1,600
-24,400
| -94% | -$5.31M |
|
3630
PUT
Vericel Corp
VCEL
$2.39B
| $360K | ﹤0.01% |
10,000
+9,400
| +1,567% | +$345K |
|
3631
CALL
Rexford Industrial Realty
REXR
$8.64B
| $360K | ﹤0.01% |
9,300
-144,100
| -94% | -$5.94M |
|
3632
CALL
Under Armour Class C
UA
$2.97B
| $360K | ﹤0.01% |
73,300
+18,000
| +33% | +$80.1K |
|
3633
Perrigo
PRGO
$1.43B
| $359K | ﹤0.01% |
25,809
+7,803
| +43% | +$130K |
|
3634
Wave Life Sciences
WVE
$1.13B
| $359K | ﹤0.01% |
21,126
+19,920
| +1,652% | +$202K |
|
3635
CALL
Tango Therapeutics
TNGX
$4.34B
| $359K | ﹤0.01% |
40,500
+29,500
| +268% | +$254K |
|
3636
CALL
Tandem Diabetes Care
TNDM
$1.22B
| $358K | ﹤0.01% |
16,300
-1,500
| -8% | -$27.1K |
|
3637
PUT
Otis Worldwide
OTIS
$28B
| $358K | ﹤0.01% |
4,100
+1,500
| +58% | +$134K |
|
|
LINE
3638
Lineage Inc
LINE
$9.7B
| $358K | ﹤0.01% |
10,231
-2,713
| -21% | -$100K |
|
|
SMLR
3639
CALL
DELISTED
Semler Scientific
SMLR
| $358K | ﹤0.01% |
23,400
-48,000
| -67% | -$1.09M |
|
3640
Emcor
EME
$31.4B
| $357K | ﹤0.01% |
584
+41
| +8% | +$26.5K |
|
3641
Rambus
RMBS
$9.49B
| $357K | ﹤0.01% |
+3,884
| New | +$382K |
|
3642
Hubbell
HUBB
$25.6B
| $357K | ﹤0.01% |
+803
| New | +$352K |
|
|
DHC
3643
Diversified Healthcare Trust
DHC
$2.23B
| $357K | ﹤0.01% |
73,527
+17,060
| +30% | +$77.4K |
|
|
SMU
3644
PUT
Tradr 2X Long SMR Daily ETF
SMU
$46M
| $356K | ﹤0.01% |
2,933
-554
| -16% | -$105K |
|
3645
PUT
Thomson Reuters
TRI
$45.1B
| $356K | ﹤0.01% |
2,658
-886
| -25% | -$128K |
|
|
BTQ
3646
CALL
BTQ Technologies Corp
BTQ
$497M
| $356K | ﹤0.01% |
+69,500
| New | +$528K |
|
3647
CALL
ClearPoint Neuro
CLPT
$436M
| $356K | ﹤0.01% |
26,000
-38,900
| -60% | -$721K |
|
|
DPRO
3648
PUT
Draganfly
DPRO
$151M
| $355K | ﹤0.01% |
51,400
+23,000
| +81% | +$194K |
|
3649
PUT
Exelixis
EXEL
$14.2B
| $355K | ﹤0.01% |
8,100
-73,000
| -90% | -$3.02M |
|
3650
CALL
Quantum-Si Incorporated
QSI
$166M
| $353K | ﹤0.01% |
321,300
+163,900
| +104% | +$267K |
|
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.