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 | |
|---|---|---|---|---|---|---|
4776
PUT
Indivior Pharmaceuticals
INDV
$4.74B
| $229K | ﹤0.01% |
9,500
-300
| -3% | -$6.28K |
|
4777
CALL
Lightpath Technologies
LPTH
$590M
| $229K | ﹤0.01% |
+29,000
| New | +$129K |
|
4778
Otis Worldwide
OTIS
$27.9B
| $229K | ﹤0.01% |
2,509
-642
| -20% | -$58.3K |
|
4779
PUT
TD Synnex
SNX
$19.9B
| $229K | ﹤0.01% |
1,400
-200
| -13% | -$29.5K |
|
4780
CALL
STAAR Surgical
STAA
$1.19B
| $228K | ﹤0.01% |
8,500
+7,400
| +673% | +$176K |
|
4781
Corbus Pharmaceuticals
CRBP
$165M
| $227K | ﹤0.01% |
17,950
+15,131
| +537% | +$144K |
|
4782
Equity Lifestyle Properties
ELS
$13.1B
| $227K | ﹤0.01% |
+3,742
| New | +$227K |
|
4783
Kodiak Sciences
KOD
$2.5B
| $227K | ﹤0.01% |
13,878
+9,003
| +185% | +$77.6K |
|
|
NFGC
4784
CALL
New Found Gold
NFGC
$526M
| $227K | ﹤0.01% |
95,900
+61,600
| +180% | +$108K |
|
4785
PUT
PTC Therapeutics
PTCT
$6.18B
| $227K | ﹤0.01% |
3,700
+2,700
| +270% | +$141K |
|
|
NAGE
4786
Niagen Bioscience
NAGE
$256M
| $227K | ﹤0.01% |
+24,398
| New | +$246K |
|
|
AGEN
4787
PUT
Agenus
AGEN
$276M
| $226K | ﹤0.01% |
58,900
+55,300
| +1,536% | +$277K |
|
4788
CALL
Associated Banc-Corp
ASB
$5.8B
| $226K | ﹤0.01% |
8,800
-3,800
| -30% | -$97.4K |
|
4789
CALL
Casey's General Stores
CASY
$32.1B
| $226K | ﹤0.01% |
400
-100
| -20% | -$52.3K |
|
4790
CALL
Health Catalyst
HCAT
$160M
| $226K | ﹤0.01% |
79,600
+200
| +0.3% | +$685 |
|
4791
CALL
Perimeter Solutions
PRM
$5.66B
| $226K | ﹤0.01% |
10,100
-1,800
| -15% | -$34.1K |
|
4792
PUT
Brown & Brown
BRO
$25.1B
| $225K | ﹤0.01% |
2,400
-11,800
| -83% | -$1.15M |
|
4793
PUT
Northwest Bancshares
NWBI
$2.33B
| $225K | ﹤0.01% |
18,200
| – | – |
|
4794
CALL
Prosperity Bancshares
PB
$8.9B
| $225K | ﹤0.01% |
3,400
+3,100
| +1,033% | +$213K |
|
4795
PUT
Wheels Up
UP
$203M
| $225K | ﹤0.01% |
6,130
+5,810
| +1,816% | +$212K |
|
4796
CALL
Expro Ltd
XPRO
$1.64B
| $225K | ﹤0.01% |
19,000
+17,600
| +1,257% | +$191K |
|
4797
PUT
AdaptHealth
AHCO
$1.47B
| $224K | ﹤0.01% |
25,100
-105,200
| -81% | -$974K |
|
4798
PUT
Healthpeak Properties
DOC
$15.5B
| $224K | ﹤0.01% |
11,700
+8,500
| +266% | +$152K |
|
4799
CALL
Magnolia Oil & Gas
MGY
$5.93B
| $224K | ﹤0.01% |
9,400
+8,800
| +1,467% | +$210K |
|
4800
Neonode
NEON
$12.6M
| $224K | ﹤0.01% |
64,248
+60,389
| +1,565% | +$1.11M |
|
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.