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 |
NVIDIA
NVDA
|
+$172M |
| 2 |
Apple
AAPL
|
+$156M |
| 3 |
Broadcom
AVGO
|
+$101M |
| 4 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$57.2M |
| 5 |
UnitedHealth
UNH
|
+$55.1M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$140M |
| 2 |
Amazon
AMZN
|
+$47.9M |
| 3 |
Netflix
NFLX
|
+$38.3M |
| 4 |
TSMC
TSM
|
+$37.3M |
| 5 |
Pfizer
PFE
|
+$36.9M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.74% |
| 2 | Communication Services | 0.19% |
| 3 | Consumer Discretionary | 0.18% |
| 4 | Healthcare | 0.17% |
| 5 | Financials | 0.14% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
876
CALL
Northrop Grumman
NOC
$75.8B
| $10.3M | 0.01% |
20,600
-18,500
| -47% | -$9.09M |
|
|
VRNA
877
PUT
DELISTED
Verona Pharma
VRNA
| $10.3M | 0.01% |
108,500
+26,500
| +32% | +$1.96M |
|
878
PUT
Bilibili
BILI
$7.32B
| $10.3M | 0.01% |
478,000
+77,600
| +19% | +$1.43M |
|
879
PUT
C3.ai
AI
$1.27B
| $10.2M | 0.01% |
414,400
+172,000
| +71% | +$3.93M |
|
|
TYNS
880
CALL
DELISTED
Direxion Daily 7-10 Year Treasury Bear 1X Shares
TYNS
| $10.2M | 0.01% |
60,500
-34,500
| -36% | -$5.8M |
|
881
CALL
GSK
GSK
$102B
| $10.2M | 0.01% |
264,700
-85,100
| -24% | -$3.25M |
|
882
PUT
Zillow
Z
$6.77B
| $10.2M | 0.01% |
145,100
-40,700
| -22% | -$2.74M |
|
883
CALL
Petrobras
PBR
$122B
| $10.1M | 0.01% |
811,300
-196,100
| -19% | -$2.35M |
|
884
PUT
Welltower
WELL
$174B
| $10.1M | 0.01% |
65,800
-1,300
| -2% | -$194K |
|
885
CALL
Dominion Energy
D
$62.8B
| $10.1M | 0.01% |
178,900
+11,100
| +7% | +$608K |
|
886
CALL
Groupon
GRPN
$966M
| $10.1M | 0.01% |
302,300
-166,600
| -36% | -$4.25M |
|
887
CALL
Autodesk
ADSK
$43.3B
| $10.1M | 0.01% |
32,600
-25,800
| -44% | -$7.32M |
|
888
CALL
Biogen
BIIB
$29.6B
| $10.1M | 0.01% |
80,100
-7,400
| -8% | -$922K |
|
|
SEI
889
PUT
Solaris Energy Infrastructure
SEI
$3.7B
| $10.1M | 0.01% |
355,500
+283,700
| +395% | +$6.68M |
|
890
CALL
Rio Tinto
RIO
$149B
| $10.1M | 0.01% |
172,400
-153,300
| -47% | -$9.05M |
|
891
CALL
T. Rowe Price
TROW
$24.6B
| $10M | 0.01% |
104,000
-19,300
| -16% | -$1.77M |
|
892
CALL
Johnson Controls International
JCI
$87.4B
| $10M | 0.01% |
95,000
-18,000
| -16% | -$1.66M |
|
893
PUT
Mirion Technologies
MIR
$4.13B
| $10M | 0.01% |
465,300
+464,900
| +116,225% | +$8.01M |
|
894
CALL
Brinker International
EAT
$7.93B
| $10M | 0.01% |
55,500
+14,400
| +35% | +$2.26M |
|
895
CALL
Clorox
CLX
$11.3B
| $9.99M | 0.01% |
83,200
+14,900
| +22% | +$1.99M |
|
896
Marvell Technology
MRVL
$188B
| $9.97M | 0.01% |
+128,883
| New | +$8.04M |
|
897
Adobe
ADBE
$84.3B
| $9.91M | 0.01% |
+25,630
| New | +$9.88M |
|
898
PUT
Moody's
MCO
$82.5B
| $9.88M | 0.01% |
19,700
+15,500
| +369% | +$7.18M |
|
|
TLN
899
CALL
Talen Energy Corp
TLN
$18.1B
| $9.86M | 0.01% |
33,900
-26,100
| -44% | -$6.19M |
|
900
PUT
ZIM Integrated Shipping Services
ZIM
$3.08B
| $9.82M | 0.01% |
610,300
-160,500
| -21% | -$2.53M |
|
Similar funds
Simplex Trading's Q2 2025 Portfolio in Review
As of Q2 2025, Simplex Trading held 10,048 positions worth $175B, up 12% from $156B the previous quarter. Its ten largest holdings account for 47% of the portfolio.
Simplex Trading withdrew a net $10.5B in Q2 2025, closing 1,431 positions and reducing 3,590 holdings. Its most notable exit was Constellation Energy, an estimated $35.8M position sold in full.
By sector, the portfolio is most concentrated in Technology at 0.74% of assets, up from 0.41% a quarter earlier, followed by Communication Services and Consumer Discretionary.
Against the trend, Simplex Trading opened a new position in State Street SPDR S&P 500 ETF Trust worth $61.9M.
- Simplex Trading's largest Q2 2025 buy was State Street SPDR S&P 500 ETF Trust: 100,129 shares worth $61.9M.
- Simplex Trading added most to NVIDIA in Q2 2025, an estimated $172M increase.
- Simplex Trading's biggest Q2 2025 reduction was iShares 20+ Year Treasury Bond ETF, cutting an estimated $140M.
- Simplex Trading fully exited Constellation Energy in Q2 2025, selling an estimated $35.8M.
- Simplex Trading's ten largest holdings make up 47% of its $175B portfolio in Q2 2025.
- Simplex Trading opened 1,525 new positions and closed 1,431 in Q2 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $175B.
Based on Simplex Trading's 13F filing for Q2 2025, filed 5 Aug 2025.