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 | |
|---|---|---|---|---|---|---|
376
PUT
Wayfair
W
$11.1B
| $45.5M | 0.02% |
508,900
-73,700
| -13% | -$5.4M |
|
377
CALL
AT&T
T
$160B
| $44.9M | 0.02% |
1,591,300
+409,800
| +35% | +$11.6M |
|
378
PUT
Avis
CAR
$5.81B
| $44.8M | 0.02% |
279,100
-167,100
| -37% | -$28.2M |
|
379
PUT
Roku
ROKU
$21.2B
| $44.7M | 0.02% |
446,400
+108,400
| +32% | +$10M |
|
380
PUT
GameStop
GME
$9.69B
| $44.7M | 0.02% |
1,638,400
+189,900
| +13% | +$4.5M |
|
381
CALL
DoorDash
DASH
$77.4B
| $44.7M | 0.02% |
164,200
+27,100
| +20% | +$6.8M |
|
382
PUT
SLB Ltd
SLB
$71.3B
| $44M | 0.02% |
1,280,800
+369,300
| +41% | +$12.9M |
|
383
PUT
KKR & Co
KKR
$85.8B
| $43.8M | 0.02% |
337,400
-56,200
| -14% | -$7.98M |
|
384
PUT
Blackrock
BLK
$164B
| $43.8M | 0.02% |
37,600
+9,300
| +33% | +$10.4M |
|
385
PUT
Interactive Brokers
IBKR
$41.7B
| $43.6M | 0.02% |
633,000
+110,400
| +21% | +$6.95M |
|
386
CALL
Snap
SNAP
$7.52B
| $43.2M | 0.02% |
5,604,500
+4,150,100
| +285% | +$34.4M |
|
387
CALL
AbbVie
ABBV
$448B
| $43.2M | 0.02% |
186,600
-187,400
| -50% | -$38.2M |
|
388
CALL
Abbott
ABT
$175B
| $43M | 0.02% |
321,100
+55,600
| +21% | +$7.3M |
|
389
CALL
RTX Corp
RTX
$262B
| $42.7M | 0.02% |
255,200
-173,700
| -40% | -$27M |
|
390
PUT
Moderna
MRNA
$23B
| $42.7M | 0.02% |
1,653,100
+26,300
| +2% | +$734K |
|
391
PUT
DraftKings
DKNG
$11.3B
| $42.6M | 0.02% |
1,139,900
-255,400
| -18% | -$11.3M |
|
392
PUT
MP Materials
MP
$8.13B
| $42.6M | 0.02% |
635,300
+398,100
| +168% | +$25M |
|
393
SoFi Technologies
SOFI
$21.9B
| $42.5M | 0.02% |
1,607,981
+227,618
| +16% | +$5.4M |
|
394
PUT
Cloudflare
NET
$95.5B
| $42.4M | 0.02% |
197,400
-90,500
| -31% | -$18.5M |
|
395
PUT
Ford
F
$57.5B
| $42.2M | 0.02% |
3,529,000
+581,000
| +20% | +$6.69M |
|
396
PUT
General Motors
GM
$74.1B
| $42.1M | 0.02% |
690,300
-107,200
| -13% | -$5.98M |
|
397
PUT
iShares Gold Trust
IAU
$64.2B
| $42.1M | 0.02% |
578,300
+25,400
| +5% | +$1.66M |
|
398
PUT
Chipotle Mexican Grill
CMG
$41.3B
| $41.8M | 0.02% |
1,067,300
-497,800
| -32% | -$22.4M |
|
399
CALL
Cipher Digital
CIFR
$10B
| $41.6M | 0.02% |
4,225,500
+3,229,100
| +324% | +$24.4M |
|
400
PUT
Affirm
AFRM
$24.8B
| $41.5M | 0.02% |
666,100
+241,000
| +57% | +$18.3M |
|
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.