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 |
Microsoft
MSFT
|
+$234M |
| 2 |
iShares Russell 2000 ETF
IWM
|
+$97.5M |
| 3 |
Amazon
AMZN
|
+$96.8M |
| 4 |
iShares Bitcoin Trust
IBIT
|
+$80.6M |
| 5 |
Pinduoduo
PDD
|
+$54.9M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
iShares 20+ Year Treasury Bond ETF
TLT
|
+$129M |
| 2 |
Alphabet (Google) Class A
GOOGL
|
+$92.9M |
| 3 |
Broadcom
AVGO
|
+$82.9M |
| 4 |
Alphabet (Google) Class C
GOOG
|
+$68.4M |
| 5 |
Meta Platforms (Facebook)
META
|
+$59.2M |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Technology | 0.79% |
| 2 | Consumer Discretionary | 0.3% |
| 3 | Healthcare | 0.25% |
| 4 | Financials | 0.17% |
| 5 | Industrials | 0.09% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
5851
PUT
Evolent Health
EVH
$348M
| $91K | ﹤0.01% |
10,800
-11,200
| -51% | -$109K |
|
5852
Omeros
OMER
$857M
| $91K | ﹤0.01% |
+22,220
| New | +$88.2K |
|
|
OTLY
5853
Oatly Group
OTLY
$465M
| $91K | ﹤0.01% |
5,635
+4,156
| +281% | +$66.9K |
|
5854
Pacific Biosciences
PACB
$435M
| $91K | ﹤0.01% |
71,768
-45,757
| -39% | -$62K |
|
5855
CALL
Puma Biotechnology
PBYI
$404M
| $91K | ﹤0.01% |
17,200
+10,700
| +165% | +$45.4K |
|
5856
CALL
RLX Technology
RLX
$2.47B
| $91K | ﹤0.01% |
34,900
+24,300
| +229% | +$57.8K |
|
|
RWT
5857
PUT
Redwood Trust
RWT
$574M
| $91K | ﹤0.01% |
15,800
+6,900
| +78% | +$41.2K |
|
|
SCS
5858
PUT
DELISTED
Steelcase
SCS
| $91K | ﹤0.01% |
+5,300
| New | +$76.5K |
|
5859
SES AI
SES
$203M
| $91K | ﹤0.01% |
+55,024
| New | +$65.8K |
|
5860
TXO Partners LP
TXO
$742M
| $91K | ﹤0.01% |
6,498
-6,694
| -51% | -$96.8K |
|
|
VLRS
5861
CALL
Controladora Vuela Compania de Aviacion
VLRS
$900M
| $91K | ﹤0.01% |
12,700
+12,300
| +3,075% | +$70.9K |
|
|
VLRS
5862
PUT
Controladora Vuela Compania de Aviacion
VLRS
$900M
| $91K | ﹤0.01% |
12,800
+11,100
| +653% | +$64K |
|
|
YRD
5863
Yiren Digital
YRD
$97.1M
| $91K | ﹤0.01% |
15,483
+13,548
| +700% | +$80.9K |
|
5864
PUT
ADC Therapeutics
ADCT
$134M
| $90K | ﹤0.01% |
22,600
-10,300
| -31% | -$32.5K |
|
5865
CALL
Black Diamond Therapeutics
BDTX
$96.8M
| $90K | ﹤0.01% |
24,000
+7,900
| +49% | +$23.1K |
|
5866
PUT
Blackbaud
BLKB
$1.94B
| $90K | ﹤0.01% |
1,400
-700
| -33% | -$45.9K |
|
5867
CALL
CareCloud
CCLD
$104M
| $90K | ﹤0.01% |
28,200
-16,300
| -37% | -$47.2K |
|
5868
Capri Holdings
CPRI
$1.83B
| $90K | ﹤0.01% |
4,542
-19,546
| -81% | -$392K |
|
5869
Customers Bancorp
CUBI
$2.66B
| $90K | ﹤0.01% |
1,387
-3,401
| -71% | -$224K |
|
|
AGNT
5870
PUT
AGNT Inc
AGNT
$666M
| $90K | ﹤0.01% |
8,500
-2,700
| -24% | -$28.6K |
|
5871
CALL
Limoneira
LMNR
$235M
| $90K | ﹤0.01% |
6,100
+4,300
| +239% | +$66.5K |
|
5872
PUT
Otter Tail
OTTR
$3.71B
| $90K | ﹤0.01% |
+1,100
| New | +$89.2K |
|
5873
PUT
Preferred Bank
PFBC
$1.24B
| $90K | ﹤0.01% |
1,000
| – | – |
|
5874
PUT
Rush Street Interactive
RSI
$2.77B
| $90K | ﹤0.01% |
4,400
-20,100
| -82% | -$379K |
|
|
SCPH
5875
CALL
DELISTED
scPharmaceuticals
SCPH
| $90K | ﹤0.01% |
124,000
-85,300
| -41% | -$437K |
|
Similar funds
Simplex Trading's Q3 2025 Portfolio in Review
As of Q3 2025, Simplex Trading held 10,358 positions worth $195B, up 12% from $175B the previous quarter. Its ten largest holdings account for 46% of the portfolio.
Simplex Trading's Q3 2025 filing shows 1,743 new, 3,828 increased, 3,250 reduced and 1,308 closed positions. Its largest new stake was Microsoft: 458,309 shares worth $237M. The largest sale was iShares 20+ Year Treasury Bond ETF, an estimated $129M.
By sector, the portfolio is most concentrated in Technology at 0.79% of assets, up from 0.74% a quarter earlier, followed by Consumer Discretionary and Healthcare.
- Simplex Trading's largest Q3 2025 buy was Microsoft: 458,309 shares worth $237M.
- Simplex Trading added most to iShares Russell 2000 ETF in Q3 2025, an estimated $97.5M increase.
- Simplex Trading's biggest Q3 2025 reduction was Alphabet (Google) Class A, cutting an estimated $92.9M.
- Simplex Trading fully exited iShares 20+ Year Treasury Bond ETF in Q3 2025, selling an estimated $129M.
- Simplex Trading's ten largest holdings make up 46% of its $195B portfolio in Q3 2025.
- Simplex Trading opened 1,743 new positions and closed 1,308 in Q3 2025.
- Simplex Trading's portfolio value rose 12% quarter-over-quarter to $195B.
Based on Simplex Trading's 13F filing for Q3 2025, filed 12 Nov 2025.