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 | |
|---|---|---|---|---|---|---|
3351
CALL
Saia
SAIA
$11.2B
| $748K | ﹤0.01% |
2,500
-15,100
| -86% | -$4.56M |
|
3352
PUT
Sportradar
SRAD
$4.34B
| $747K | ﹤0.01% |
27,800
+12,000
| +76% | +$356K |
|
3353
PUT
Fox Class B
FOX
$21.3B
| $746K | ﹤0.01% |
11,900
-4,100
| -26% | -$216K |
|
3354
CALL
MSC Industrial Direct
MSM
$7.07B
| $746K | ﹤0.01% |
8,100
-1,500
| -16% | -$134K |
|
3355
PUT
NextDecade
NEXT
$1.7B
| $745K | ﹤0.01% |
109,800
-295,100
| -73% | -$2.85M |
|
3356
PUT
Liberty Energy
LBRT
$2.75B
| $744K | ﹤0.01% |
60,300
+31,200
| +107% | +$361K |
|
3357
PUT
Pool Corp
POOL
$6.73B
| $744K | ﹤0.01% |
2,400
-1,300
| -35% | -$407K |
|
3358
PUT
Rogers Communications
RCI
$17.7B
| $744K | ﹤0.01% |
21,600
+17,600
| +440% | +$606K |
|
3359
Invesco Solar ETF
TAN
$1.48B
| $744K | ﹤0.01% |
+17,064
| New | +$682K |
|
3360
Atmus Filtration Technologies
ATMU
$4.43B
| $743K | ﹤0.01% |
+16,500
| New | +$692K |
|
3361
CALL
Delek Logistics
DKL
$3.03B
| $742K | ﹤0.01% |
16,300
-4,500
| -22% | -$199K |
|
3362
PUT
Digital Turbine
APPS
$1.04B
| $739K | ﹤0.01% |
115,600
-20,400
| -15% | -$101K |
|
|
3363
CALL
Digital Turbine
APPS
$1.04B
| $738K | ﹤0.01% |
115,400
-48,900
| -30% | -$243K |
|
3364
Freshworks
FRSH
$2.99B
| $736K | ﹤0.01% |
62,572
+56,003
| +853% | +$754K |
|
3365
Groupon
GRPN
$1.05B
| $736K | ﹤0.01% |
31,524
+15,995
| +103% | +$460K |
|
|
VMEO
3366
DELISTED
Vimeo
VMEO
| $736K | ﹤0.01% |
94,979
+88,474
| +1,360% | +$435K |
|
3367
Critical Metals Corp
CRML
$887M
| $736K | ﹤0.01% |
+118,354
| New | +$607K |
|
|
TBCH
3368
PUT
Turtle Beach Corp
TBCH
$245M
| $736K | ﹤0.01% |
46,300
+2,400
| +5% | +$35.7K |
|
3369
Hallador Energy
HNRG
$717M
| $731K | ﹤0.01% |
37,391
+37,327
| +58,323% | +$641K |
|
3370
PUT
Aecom
ACM
$9.12B
| $730K | ﹤0.01% |
5,600
+4,000
| +250% | +$483K |
|
3371
CALL
CoreCivic
CXW
$3.09B
| $730K | ﹤0.01% |
35,900
-9,100
| -20% | -$189K |
|
3372
CALL
Harmony Biosciences
HRMY
$2.08B
| $730K | ﹤0.01% |
26,500
+24,700
| +1,372% | +$851K |
|
3373
Adient
ADNT
$1.62B
| $729K | ﹤0.01% |
30,306
-6,524
| -18% | -$152K |
|
3374
CALL
Ecopetrol
EC
$32.5B
| $729K | ﹤0.01% |
79,200
-18,700
| -19% | -$168K |
|
3375
AtaiBeckley Inc
ATAI
$2.65B
| $728K | ﹤0.01% |
137,642
+58,109
| +73% | +$236K |
|
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.