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 | |
|---|---|---|---|---|---|---|
|
PLG
5601
CALL
Platinum Group Metals
PLG
$164M
| $113K | ﹤0.01% |
+42,700
| New | +$72.8K |
|
|
RPTX
5602
CALL
DELISTED
Repare Therapeutics
RPTX
| $113K | ﹤0.01% |
64,300
+60,700
| +1,686% | +$97.2K |
|
5603
Boston Beer
SAM
$1.91B
| $113K | ﹤0.01% |
+539
| New | +$115K |
|
|
BTCL
5604
T-Rex 2X Long Bitcoin Daily Target ETF
BTCL
$21.8M
| $113K | ﹤0.01% |
2,027
+762
| +60% | +$44.6K |
|
|
BCAX
5605
PUT
Bicara Therapeutics
BCAX
$1.78B
| $113K | ﹤0.01% |
7,200
+6,600
| +1,100% | +$73.9K |
|
5606
Certara
CERT
$1.26B
| $112K | ﹤0.01% |
+9,172
| New | +$100K |
|
|
COOP
5607
CALL
DELISTED
Mr. Cooper
COOP
| $112K | ﹤0.01% |
2,100
+1,100
| +110% | +$203K |
|
|
FBRT
5608
PUT
Franklin BSP Realty Trust
FBRT
$630M
| $112K | ﹤0.01% |
10,400
+2,700
| +35% | +$29.8K |
|
5609
CALL
Perella Weinberg Partners
PWP
$1.29B
| $112K | ﹤0.01% |
+5,300
| New | +$113K |
|
|
SJT
5610
PUT
San Juan Basin Royalty Trust
SJT
$117M
| $112K | ﹤0.01% |
18,700
+5,600
| +43% | +$32.9K |
|
5611
TaskUs
TASK
$556M
| $112K | ﹤0.01% |
6,289
+800
| +15% | +$13.8K |
|
|
RPT
5612
CALL
Rithm Property Trust
RPT
$95.8M
| $112K | ﹤0.01% |
+7,433
| New | +$118K |
|
5613
CALL
Alector
ALEC
$168M
| $111K | ﹤0.01% |
37,500
-55,300
| -60% | -$122K |
|
5614
PUT
Apogee Therapeutics
APGE
$10.1B
| $111K | ﹤0.01% |
2,800
+1,400
| +100% | +$53.5K |
|
5615
Ardmore Shipping
ASC
$710M
| $111K | ﹤0.01% |
9,433
+5,880
| +165% | +$65.9K |
|
5616
PUT
Alphatec Holdings
ATEC
$1.46B
| $111K | ﹤0.01% |
7,700
-300
| -4% | -$4.18K |
|
5617
CALL
California Resources
CRC
$4.67B
| $111K | ﹤0.01% |
2,100
-500
| -19% | -$25.1K |
|
5618
CALL
Dream Finders Homes
DFH
$1.16B
| $111K | ﹤0.01% |
4,300
+4,000
| +1,333% | +$110K |
|
5619
Douglas Elliman
DOUG
$154M
| $111K | ﹤0.01% |
39,016
+15,885
| +69% | +$41.7K |
|
5620
InflaRx
IFRX
$250M
| $111K | ﹤0.01% |
83,457
+57,745
| +225% | +$61.3K |
|
5621
CALL
MediaAlpha
MAX
$758M
| $111K | ﹤0.01% |
9,800
+8,800
| +880% | +$97.1K |
|
5622
CALL
NMI Holdings
NMIH
$3.33B
| $111K | ﹤0.01% |
2,900
| – | – |
|
5623
CALL
Paylocity
PCTY
$7.38B
| $111K | ﹤0.01% |
700
-1,200
| -63% | -$212K |
|
5624
Satellogic
SATL
$531M
| $111K | ﹤0.01% |
+33,979
| New | +$120K |
|
5625
Tenable Holdings
TENB
$3.6B
| $111K | ﹤0.01% |
+3,823
| New | +$119K |
|
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.