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 | |
|---|---|---|---|---|---|---|
5201
CALL
John B. Sanfilippo & Son
JBSS
$967M
| $160K | ﹤0.01% |
2,500
+2,200
| +733% | +$142K |
|
5202
Pegasystems
PEGA
$5.02B
| $160K | ﹤0.01% |
+2,799
| New | +$154K |
|
5203
PUT
Repligen
RGEN
$7.96B
| $160K | ﹤0.01% |
1,200
+800
| +200% | +$97.2K |
|
5204
CALL
Sabra Healthcare REIT
SBRA
$5.34B
| $160K | ﹤0.01% |
8,600
-7,000
| -45% | -$131K |
|
5205
CALL
Skywest
SKYW
$4.24B
| $160K | ﹤0.01% |
1,600
+700
| +78% | +$78.2K |
|
5206
CALL
Wabtec
WAB
$49.1B
| $160K | ﹤0.01% |
800
-1,400
| -64% | -$276K |
|
5207
CALL
Delcath Systems
DCTH
$422M
| $159K | ﹤0.01% |
14,800
-4,800
| -24% | -$53.6K |
|
|
EMX
5208
PUT
DELISTED
EMX Royalty
EMX
| $159K | ﹤0.01% |
30,900
+29,400
| +1,960% | +$102K |
|
|
TDAY
5209
PUT
USA Today Co
TDAY
$1.27B
| $159K | ﹤0.01% |
38,500
+13,500
| +54% | +$54.2K |
|
|
LNW
5210
PUT
DELISTED
Light & Wonder
LNW
| $159K | ﹤0.01% |
1,900
+300
| +19% | +$27.5K |
|
|
OGI
5211
CALL
Organigram Holdings
OGI
$132M
| $159K | ﹤0.01% |
78,700
+51,500
| +189% | +$80.9K |
|
|
ACH
5212
Accendra Health
ACH
$237M
| $159K | ﹤0.01% |
33,170
+12,676
| +62% | +$80.6K |
|
|
PDM
5213
CALL
Piedmont Realty Trust
PDM
$1.21B
| $159K | ﹤0.01% |
17,700
+9,200
| +108% | +$74K |
|
5214
ProShares VIX Short-Term Futures ETF
VIXY
$201M
| $159K | ﹤0.01% |
4,924
+4,801
| +3,903% | +$185K |
|
|
UPB
5215
PUT
Upstream Bio Inc
UPB
$343M
| $159K | ﹤0.01% |
+8,500
| New | +$132K |
|
5216
Vanda Pharmaceuticals
VNDA
$307M
| $158K | ﹤0.01% |
31,679
-30,637
| -49% | -$142K |
|
5217
CALL
Future Fuel
FF
$217M
| $157K | ﹤0.01% |
40,600
-9,300
| -19% | -$36.7K |
|
|
HDSN
5218
Hudson Technologies
HDSN
$254M
| $157K | ﹤0.01% |
15,867
-73,563
| -82% | -$690K |
|
5219
Kinsale Capital Group
KNSL
$8.12B
| $157K | ﹤0.01% |
371
-253
| -41% | -$115K |
|
|
LPRO
5220
Open Lending Corp
LPRO
| $157K | ﹤0.01% |
+74,527
| New | +$168K |
|
5221
PUT
National Fuel Gas
NFG
$7.82B
| $157K | ﹤0.01% |
1,700
+1,500
| +750% | +$131K |
|
5222
PUT
Xeris Biopharma Holdings
XERS
$1.39B
| $157K | ﹤0.01% |
19,300
+5,100
| +36% | +$33.9K |
|
|
ADVM
5223
PUT
DELISTED
Adverum Biotechnologies
ADVM
| $156K | ﹤0.01% |
+34,600
| New | +$102K |
|
5224
Biogen
BIIB
$30B
| $156K | ﹤0.01% |
1,116
-5,483
| -83% | -$741K |
|
5225
PUT
Koppers
KOP
$943M
| $156K | ﹤0.01% |
5,600
+4,500
| +409% | +$139K |
|
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.