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 |
Tesla
TSLA
|
+$33.5M |
| 2 |
Netflix
NFLX
|
+$22.8M |
| 3 |
State Street SPDR Dow Jones Industrial Average ETF Trust
DIA
|
+$20.9M |
| 4 |
TWX
Time Warner Inc
TWX
|
+$18.3M |
| 5 |
Alibaba
BABA
|
+$15.2M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Amazon
AMZN
|
+$71.1M |
| 2 |
Micron Technology
MU
|
+$43.8M |
| 3 |
Alphabet (Google) Class C
GOOG
|
+$26.3M |
| 4 |
Booking.com
BKNG
|
+$22.2M |
| 5 |
Boeing
BA
|
+$21.6M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Consumer Discretionary | 7.87% |
| 2 | Communication Services | 7.14% |
| 3 | Technology | 6.23% |
| 4 | Financials | 5.5% |
| 5 | Healthcare | 5.2% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
476
First Trust Dow Jones Internet Index Fund ETF
FDN
$4.84B
| $810K | 0.04% |
6,729
+3,974
| +144% | +$481K |
|
477
Atlassian
TEAM
$20.3B
| $807K | 0.04% |
+14,985
| New | +$815K |
|
478
PUT
Teva Pharmaceuticals
TEVA
$36.3B
| $807K | 0.04% |
2,794
-33
| -1% | -$644 |
|
479
CALL
Baidu
BIDU
$36.5B
| $804K | 0.04% |
2,215
-3,221
| -59% | -$794K |
|
|
ZEN
480
DELISTED
ZENDESK INC
ZEN
| $804K | 0.04% |
16,804
+10,742
| +177% | +$445K |
|
|
VIAB
481
DELISTED
Viacom Inc. Class B
VIAB
| $804K | 0.04% |
25,903
+16,381
| +172% | +$529K |
|
482
Realty Income
O
$60.4B
| $802K | 0.04% |
+16,001
| New | +$797K |
|
|
MIC
483
DELISTED
Macquarie Infrastructure Holdings, LLC
MIC
| $802K | 0.04% |
+21,720
| New | +$1.17M |
|
484
Targa Resources
TRGP
$61.3B
| $800K | 0.04% |
18,196
+5,632
| +45% | +$268K |
|
485
Axalta
AXTA
$6.78B
| $798K | 0.04% |
+26,442
| New | +$826K |
|
486
D.R. Horton
DHI
$39.9B
| $795K | 0.04% |
+18,149
| New | +$847K |
|
487
Mid-America Apartment Communities
MAA
$15.5B
| $795K | 0.04% |
8,716
+2,765
| +46% | +$250K |
|
488
PUT
Morgan Stanley
MS
$338B
| $793K | 0.03% |
5,011
-1,475
| -23% | -$81.6K |
|
489
Varonis Systems
VRNS
$5.14B
| $793K | 0.03% |
39,363
+38,790
| +6,770% | +$718K |
|
|
SIVB
490
DELISTED
SVB Financial Group
SIVB
| $793K | 0.03% |
3,306
+1,703
| +106% | +$427K |
|
491
CALL
Abbott
ABT
$175B
| $786K | 0.03% |
1,495
+292
| +24% | +$17.6K |
|
|
WBC
492
DELISTED
WABCO HOLDINGS INC.
WBC
| $786K | 0.03% |
+5,875
| New | +$851K |
|
493
PUT
Lam Research
LRCX
$400B
| $784K | 0.03% |
14,550
-3,880
| -21% | -$76.9K |
|
494
CALL
Bristol-Myers Squibb
BMY
$126B
| $781K | 0.03% |
4,242
+771
| +22% | +$49.6K |
|
|
BEAT
495
CALL
DELISTED
BioTelemetry, Inc.
BEAT
| $780K | 0.03% |
24,988
+24,962
| +96,008% | +$821K |
|
496
Iovance Biotherapeutics
IOVA
$2.29B
| $779K | 0.03% |
+46,119
| New | +$698K |
|
497
KB Home
KBH
$3.41B
| $779K | 0.03% |
27,386
+21,227
| +345% | +$661K |
|
498
PUT
Molson Coors Class B
TAP
$7.51B
| $779K | 0.03% |
359
-133
| -27% | -$10.6K |
|
499
Under Armour Class C
UA
$2.81B
| $779K | 0.03% |
54,331
-7,574
| -12% | -$107K |
|
500
Direxion Daily Gold Miners Index Bull 2X ETF
NUGT
$860M
| $775K | 0.03% |
+6,358
| New | +$882K |
|
Similar funds
Simplex Trading's Q1 2018 Portfolio in Review
As of Q1 2018, Simplex Trading held 7,591 positions worth $2.27B, down 2.1% from $2.32B the previous quarter. Its ten largest holdings account for 18% of the portfolio.
Simplex Trading withdrew a net $210M in Q1 2018, closing 1,502 positions and reducing 2,267 holdings. Its most notable exit was Alphabet (Google) Class C, an estimated $26.3M position sold in full.
By sector, the portfolio is most concentrated in Consumer Discretionary at 7.9% of assets, down from 11% a quarter earlier, followed by Communication Services and Technology.
Against the trend, Simplex Trading opened a new position in Tesla worth $27.1M.
- Simplex Trading's largest Q1 2018 buy was Tesla: 1,525,035 shares worth $27.1M.
- Simplex Trading added most to Netflix in Q1 2018, an estimated $22.8M increase.
- Simplex Trading's biggest Q1 2018 reduction was Amazon, cutting an estimated $71.1M.
- Simplex Trading fully exited Alphabet (Google) Class C in Q1 2018, selling an estimated $26.3M.
- Simplex Trading's ten largest holdings make up 18% of its $2.27B portfolio in Q1 2018.
- Simplex Trading opened 1,643 new positions and closed 1,502 in Q1 2018.
- Simplex Trading's portfolio value fell 2.1% quarter-over-quarter to $2.27B.
Based on Simplex Trading's 13F filing for Q1 2018, filed 26 Apr 2018.