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 | |
|---|---|---|---|---|---|---|
4901
PUT
Adient
ADNT
$1.72B
| $207K | ﹤0.01% |
8,600
-700
| -8% | -$16.4K |
|
4902
CALL
Commault Systems
CVLT
$4.82B
| $207K | ﹤0.01% |
1,100
-3,000
| -73% | -$541K |
|
4903
CALL
Immersion
IMMR
$246M
| $207K | ﹤0.01% |
28,300
-7,600
| -21% | -$55.1K |
|
4904
CALL
Inspired Entertainment
INSE
$182M
| $207K | ﹤0.01% |
22,100
+1,800
| +9% | +$16.2K |
|
4905
Spear Alpha ETF
SPRX
$199M
| $207K | ﹤0.01% |
5,378
+5,227
| +3,462% | +$178K |
|
|
XRPT
4906
Volatility Shares Trust XRP 2X ETF
XRPT
$54.7M
| $207K | ﹤0.01% |
670
+455
| +212% | +$171K |
|
|
AMRN
4907
CALL
Amarin Corp
AMRN
$298M
| $206K | ﹤0.01% |
12,600
-7,100
| -36% | -$110K |
|
4908
PUT
Acuity Brands
AYI
$10.1B
| $206K | ﹤0.01% |
600
+500
| +500% | +$159K |
|
4909
CALL
Interparfums
IPAR
$4.02B
| $206K | ﹤0.01% |
2,100
-400
| -16% | -$47.1K |
|
4910
Waters Corp
WAT
$37.3B
| $206K | ﹤0.01% |
+688
| New | +$208K |
|
|
MAGN
4911
PUT
Magnera Corp
MAGN
$475M
| $206K | ﹤0.01% |
17,600
+8,700
| +98% | +$108K |
|
4912
Trex
TREX
$4.56B
| $205K | ﹤0.01% |
3,977
+253
| +7% | +$15.4K |
|
|
ZENA
4913
CALL
ZenaTech Inc
ZENA
$116M
| $205K | ﹤0.01% |
42,900
+29,200
| +213% | +$145K |
|
|
JBIO
4914
PUT
Jade Biosciences
JBIO
$1.22B
| $204K | ﹤0.01% |
23,700
-2,200
| -8% | -$18K |
|
|
BHR
4915
CALL
Braemar Hotels & Resorts
BHR
$160M
| $204K | ﹤0.01% |
+75,000
| New | +$190K |
|
4916
Ocular Therapeutix
OCUL
$1.85B
| $204K | ﹤0.01% |
17,460
-44,118
| -72% | -$528K |
|
4917
CALL
The RMR Group
RMR
$333M
| $204K | ﹤0.01% |
13,000
+10,900
| +519% | +$182K |
|
4918
Parker-Hannifin
PH
$121B
| $203K | ﹤0.01% |
+269
| New | +$198K |
|
4919
Rezolute
RZLT
$470M
| $203K | ﹤0.01% |
21,701
+13,067
| +151% | +$87K |
|
|
AGEN
4920
CALL
Agenus
AGEN
$329M
| $202K | ﹤0.01% |
52,500
-7,600
| -13% | -$38.1K |
|
4921
Amplify Blockchain Technology ETF
BLOK
$1.09B
| $202K | ﹤0.01% |
3,017
+1,758
| +140% | +$107K |
|
4922
CALL
Haleon
HLN
$44.5B
| $202K | ﹤0.01% |
22,600
+21,000
| +1,313% | +$202K |
|
4923
Napco Security Technologies
NSSC
$1.3B
| $202K | ﹤0.01% |
+4,710
| New | +$163K |
|
|
NTST
4924
PUT
NETSTREIT Corp
NTST
$2.1B
| $202K | ﹤0.01% |
11,200
+10,800
| +2,700% | +$195K |
|
|
ZH
4925
CALL
Zhihu
ZH
$282M
| $202K | ﹤0.01% |
39,900
+36,000
| +923% | +$170K |
|
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.