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 |
iShares Russell 2000 ETF
IWM
|
+$67.5M |
| 2 |
Palantir
PLTR
|
+$64.7M |
| 3 |
PARA
Paramount Global Class B
PARA
|
+$31.5M |
| 4 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$30.7M |
| 5 |
Carnival Corporation Ltd
CCL
|
+$25.7M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Amazon
AMZN
|
+$66M |
| 2 |
Tesla
TSLA
|
+$53.7M |
| 3 |
Alphabet (Google) Class C
GOOG
|
+$38.1M |
| 4 |
Invesco QQQ Trust
QQQ
|
+$37.6M |
| 5 |
AutoZone
AZO
|
+$28.5M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Miscellaneous | 97.22% |
| 2 | Technology | 0.66% |
| 3 | Consumer Discretionary | 0.49% |
| 4 | Healthcare | 0.33% |
| 5 | Financials | 0.3% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
9601
Navient
NAVI
$903M
| – | – |
-12,071
| Closed | -$149K |
|
9602
Neurocrine Biosciences
NBIX
$15.8B
| – | – |
-1,162
| Closed | -$122K |
|
9603
NBT Bancorp
NBTB
$2.72B
| – | – |
-1,115
| Closed | -$41K |
|
9604
CALL
Nasdaq
NDAQ
$54.2B
| – | – |
-357
| Closed | -$1.58M |
|
|
9605
Nasdaq
NDAQ
$54.2B
| – | – |
-4,359
| Closed | -$207K |
|
|
9606
PUT
Nasdaq
NDAQ
$54.2B
| – | – |
-303
| Closed | -$1.34M |
|
9607
Noodles & Co
NDLS
$85.4M
| – | – |
-6,117
| Closed | -$475K |
|
|
9608
PUT
Noodles & Co
NDLS
$85.4M
| – | – |
-5
| Closed | -$33K |
|
9609
CALL
Nordson
NDSN
$17.7B
| – | – |
-10
| Closed | -$200K |
|
9610
NextEra Energy
NEE
$174B
| $0 | ﹤0.01% |
13
-21,162
| -100% | -$1.65M |
|
9611
CALL
Newmont
NEM
$135B
| – | – |
-1,122
| Closed | -$6.72M |
|
|
9612
Newmont
NEM
$135B
| $0 | ﹤0.01% |
49,750
-169,226
| -77% | -$10.1M |
|
|
9613
PUT
Newmont
NEM
$135B
| – | – |
-3,306
| Closed | -$19.8M |
|
9614
Neogen
NEOG
$2.58B
| – | – |
-7,690
| Closed | -$322K |
|
9615
CALL
NeoGenomics
NEO
$2.23B
| – | – |
-45
| Closed | -$242K |
|
|
9616
NeoGenomics
NEO
$2.23B
| $0 | ﹤0.01% |
8,368
-7,999
| -49% | -$416K |
|
|
9617
PUT
NeoGenomics
NEO
$2.23B
| – | – |
-83
| Closed | -$446K |
|
9618
PUT
NewMarket
NEU
$8.14B
| – | – |
-1
| Closed | -$39K |
|
9619
PUT
Neurogene
NGNE
$772M
| – | – |
-2
| Closed | -$43K |
|
9620
Nice
NICE
$6.18B
| – | – |
-3,468
| Closed | -$868K |
|
9621
CALL
NN Inc
NNBR
$302M
| – | – |
-24
| Closed | -$15K |
|
|
9622
PUT
NN Inc
NNBR
$302M
| – | – |
-10
| Closed | -$6K |
|
|
NOAH
9623
CALL
Noah Holdings
NOAH
$579M
| – | – |
-26
| Closed | -$124K |
|
9624
CALL
Northern Oil and Gas
NOG
$2.76B
| – | – |
-1,710
| Closed | -$1.5M |
|
|
9625
Northern Oil and Gas
NOG
$2.76B
| $0 | ﹤0.01% |
+34,508
| New | +$414K |
|
Similar funds
Simplex Trading's Q1 2021 Portfolio in Review
As of Q1 2021, Simplex Trading held 10,706 positions worth $55.7B, down 28% from $77.2B the previous quarter. Its ten largest holdings account for 43% of the portfolio.
Simplex Trading's Q1 2021 filing shows 2,255 new, 3,360 increased, 3,150 reduced and 1,707 closed positions. Its largest new stake was Pfizer: 464,628 shares worth $16.8M. The largest sale was Amazon, an estimated $66M.
By sector, the portfolio is most concentrated in Miscellaneous at 97% of assets, down from 98% a quarter earlier, followed by Technology and Consumer Discretionary.
- Simplex Trading's largest Q1 2021 buy was Pfizer: 464,628 shares worth $16.8M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q1 2021, an estimated $67.5M increase.
- Simplex Trading's biggest Q1 2021 reduction was Amazon, cutting an estimated $66M.
- Simplex Trading fully exited Alphabet (Google) Class C in Q1 2021, selling an estimated $38.1M.
- Simplex Trading's ten largest holdings make up 43% of its $55.7B portfolio in Q1 2021.
- Simplex Trading opened 2,255 new positions and closed 1,707 in Q1 2021.
- Simplex Trading's portfolio value fell 28% quarter-over-quarter to $55.7B.
Based on Simplex Trading's 13F filing for Q1 2021, filed 26 Apr 2021.