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 | |
|---|---|---|---|---|---|---|
276
PUT
Western Digital
WDC
$169B
| $20.6M | 0.04% |
4,079
-214
| -5% | -$10K |
|
277
PUT
State Street SPDR S&P MIDCAP 400 ETF Trust
MDY
$26.5B
| $20.6M | 0.04% |
432
-185
| -30% | -$84.4K |
|
278
CALL
TripAdvisor
TRIP
$1.09B
| $20.5M | 0.04% |
3,807
+1,372
| +56% | +$58.9K |
|
279
CALL
Wynn Resorts
WYNN
$9.43B
| $20.4M | 0.04% |
1,631
-3,724
| -70% | -$449K |
|
280
XPeng
XPEV
$10.5B
| $20.4M | 0.04% |
558,889
+152,618
| +38% | +$6.34M |
|
281
PUT
Intuit
INTU
$91B
| $20.3M | 0.04% |
531
+26
| +5% | +$10K |
|
282
CALL
Vale
VALE
$65B
| $20.3M | 0.04% |
11,699
-3,769
| -24% | -$65.8K |
|
283
PUT
QuantumScape Corp
QS
$3.37B
| $19.9M | 0.04% |
4,451
-1,744
| -28% | -$91.5K |
|
284
Lam Research
LRCX
$385B
| $19.8M | 0.04% |
333,470
+211,250
| +173% | +$11.5M |
|
285
CALL
Prudential Financial
PRU
$42.1B
| $19.7M | 0.04% |
2,162
-314
| -13% | -$26.9K |
|
286
CALL
Thermo Fisher Scientific
TMO
$227B
| $19.6M | 0.04% |
429
-131
| -23% | -$62.5K |
|
|
PSTH
287
PUT
DELISTED
Pershing Square Tontine Holdings, Ltd.
PSTH
| $19.4M | 0.03% |
8,094
+6,044
| +295% | +$169K |
|
288
CALL
Crown Castle
CCI
$32.3B
| $19.4M | 0.03% |
1,127
+587
| +109% | +$94K |
|
|
FTCH
289
PUT
DELISTED
Farfetch Limited Class A Ordinary Shares
FTCH
| $19.2M | 0.03% |
3,630
+2,277
| +168% | +$139K |
|
290
CALL
RH
RH
$2.8B
| $19.2M | 0.03% |
322
+126
| +64% | +$62.1K |
|
291
CALL
lululemon athletica
LULU
$11.1B
| $19.2M | 0.03% |
625
-478
| -43% | -$157K |
|
|
SHNY
292
PUT
DELISTED
Direxion Daily Silver Miners Index Bull 2X Shares
SHNY
| $18.9M | 0.03% |
5,907
+416
| +8% | +$1.33M |
|
293
CALL
Clorox
CLX
$11.3B
| $18.8M | 0.03% |
973
-304
| -24% | -$58.5K |
|
294
Marathon Digital Holdings
MARA
$4.37B
| $18.7M | 0.03% |
390,368
+282,342
| +261% | +$8.75M |
|
295
CALL
ASML
ASML
$659B
| $18.7M | 0.03% |
303
-65
| -18% | -$36K |
|
296
CALL
Unity
U
$18.3B
| $18.7M | 0.03% |
1,861
+1,094
| +143% | +$135K |
|
|
PSTH
297
CALL
DELISTED
Pershing Square Tontine Holdings, Ltd.
PSTH
| $18.7M | 0.03% |
7,774
+5,696
| +274% | +$160K |
|
298
CALL
Gaotu Techedu
GOTU
$517M
| $18.6M | 0.03% |
5,488
+1,544
| +39% | +$126K |
|
299
PUT
RingCentral
RNG
$6.13B
| $18.6M | 0.03% |
+624
| New | +$229K |
|
300
PUT
First Solar
FSLR
$22B
| $18.5M | 0.03% |
+2,122
| New | +$195K |
|
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.