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 | |
|---|---|---|---|---|---|---|
|
OPTU
4576
CALL
Optimum Communications Inc
OPTU
$298M
| $276K | ﹤0.01% |
114,800
+11,300
| +11% | +$27.7K |
|
|
GRFS
4577
CALL
Grifois
GRFS
$5.55B
| $276K | ﹤0.01% |
27,800
+22,200
| +396% | +$222K |
|
4578
CALL
PTC Therapeutics
PTCT
$6.18B
| $276K | ﹤0.01% |
4,500
+600
| +15% | +$31.3K |
|
|
SGMO
4579
CALL
DELISTED
SANGAMO THERAPEUTICS INC
SGMO
| $276K | ﹤0.01% |
411,300
+298,400
| +264% | +$161K |
|
4580
PUT
Bausch + Lomb
BLCO
$5.78B
| $275K | ﹤0.01% |
18,300
+2,100
| +13% | +$30.3K |
|
4581
CALL
Cogent Biosciences
COGT
$6.76B
| $275K | ﹤0.01% |
19,200
+9,900
| +106% | +$117K |
|
|
GOOS
4582
PUT
Canada Goose Holdings
GOOS
$903M
| $275K | ﹤0.01% |
20,000
-55,900
| -74% | -$725K |
|
4583
PUT
POSCO
PKX
$14.7B
| $275K | ﹤0.01% |
5,600
+4,300
| +331% | +$232K |
|
|
PSIX
4584
CALL
Power Solutions International
PSIX
$586M
| $275K | ﹤0.01% |
+2,800
| New | +$248K |
|
4585
Designer Brands
DBI
$315M
| $274K | ﹤0.01% |
77,624
-10,897
| -12% | -$37.6K |
|
4586
Domo
DOMO
$171M
| $274K | ﹤0.01% |
17,298
-100,340
| -85% | -$1.55M |
|
4587
PUT
Flux Power
FLUX
$10.9M
| $274K | ﹤0.01% |
+73,400
| New | +$149K |
|
4588
CALL
Granite Construction
GVA
$5.16B
| $274K | ﹤0.01% |
2,500
-1,200
| -32% | -$123K |
|
4589
LifeMD
LFMD
$176M
| $274K | ﹤0.01% |
40,379
-58,505
| -59% | -$483K |
|
4590
CALL
Under Armour Class C
UA
$2.95B
| $274K | ﹤0.01% |
55,300
-27,700
| -33% | -$155K |
|
4591
Akebia Therapeutics
AKBA
$338M
| $273K | ﹤0.01% |
100,103
-92,931
| -48% | -$309K |
|
4592
CALL
Brookfield Asset Management
BAM
$75.6B
| $273K | ﹤0.01% |
4,800
+2,000
| +71% | +$119K |
|
4593
CALL
Pathward Financial
CASH
$1.88B
| $273K | ﹤0.01% |
3,700
+3,300
| +825% | +$257K |
|
4594
PUT
Eton Pharmaceutcials
ETON
$1.32B
| $273K | ﹤0.01% |
+12,600
| New | +$209K |
|
4595
Virtu Financial
VIRT
$5.04B
| $273K | ﹤0.01% |
+7,694
| New | +$316K |
|
|
CRESY
4596
PUT
Cresud
CRESY
$806M
| $272K | ﹤0.01% |
29,850
-7,060
| -19% | -$72.6K |
|
4597
Krispy Kreme
DNUT
$562M
| $272K | ﹤0.01% |
70,448
+25,467
| +57% | +$87.8K |
|
|
FYBR
4598
CALL
DELISTED
Frontier Communications
FYBR
| $272K | ﹤0.01% |
7,300
-4,500
| -38% | -$166K |
|
4599
Seadrill
SDRL
$2.59B
| $271K | ﹤0.01% |
8,977
-2,692
| -23% | -$82K |
|
4600
CALL
Adaptive Biotechnologies
ADPT
$3.61B
| $270K | ﹤0.01% |
18,100
-14,800
| -45% | -$180K |
|
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.