This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/stocks/MASI/capital-change-brief"
Use Arkolith's capital_change_brief for MASI. Tell me what changed, whether insider activity corroborates it, and cite the SEC evidence.
| # | Fund | Position value | Shares | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | $826.1M | 4.6M | ▼−48% Reduced · −4.2M sh | Q1 2026 | |
| 2 | Politan Capital Management LP | $816.4M | 4.6M | —Held | Q1 2026 | |
| 3 | Pentwater Capital Management LP | $564.9M | 3.2M | ▲New +3.2M sh | Q1 2026 | |
| 4 | BARCLAYS PLC | $488.1M | 2.7M | ▲47× Added · +2.7M sh | Q1 2026 | |
| 5 | HBK INVESTMENTS L P | $458.2M | 2.6M | ▲New +2.6M sh | Q1 2026 | |
| 6 | MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $416.7M | 2.3M | ▼−12% Reduced · −321K sh | Q1 2026 | |
| 7 | VANGUARD CAPITAL MANAGEMENT LLC | $364.6M | 2.1M | ▲New +2.1M sh | Q1 2026 | |
| 8 | VANGUARD PORTFOLIO MANAGEMENT LLC | $357.0M | 2.0M | ▲New +2.0M sh | Q1 2026 | |
| 9 | FMR LLC | $258.1M | 1.5M | ▼−82% Reduced · −6.4M sh | Q1 2026 | |
| 10 | STATE STREET CORP | $255.7M | 1.4M | ▲+1.6% Added · +23K sh | Q1 2026 | |
| 11 | MILLENNIUM MANAGEMENT LLC | $175.9M | 989K | ▲+426% Added · +801K sh | Q1 2026 | |
| 12 | GOLDMAN SACHS GROUP INC | $175.1M | 984K | ▲+55% Added · +347K sh | Q1 2026 | |
| 13 | GEODE CAPITAL MANAGEMENT, LLC | $170.2M | 957K | ▲+0.3% Added · +3K sh | Q1 2026 | |
| 14 | AQR CAPITAL MANAGEMENT LLC | $147.4M | 832K | ▼−24% Reduced · −259K sh | Q1 2026 | |
| 15 | BALYASNY ASSET MANAGEMENT L.P. | $137.1M | 771K | ▲New +771K sh | Q1 2026 | |
| 16 | MORGAN STANLEY | $133.8M | 752K | ▼−18% Reduced · −168K sh | Q1 2026 | |
| 17 | JPMORGAN CHASE & CO | $101.5M | 573K | ▲+386% Added · +455K sh | Q1 2026 | |
| 18 | CITIGROUP INC | $94.9M | 533K | ▲+340% Added · +412K sh | Q1 2026 | |
| 19 | FIL Ltd | $85.7M | 482K | ▲New +482K sh | Q1 2026 | |
| 20 | First Trust Capital Management L.P. | $85.3M | 479K | ▲New +479K sh | Q1 2026 | |
| 21 | HSBC HOLDINGS PLC | $84.3M | 473K | ▲New +473K sh | Q1 2026 | |
| 22 | UBS Group AG | $83.3M | 468K | ▼−22% Reduced · −131K sh | Q1 2026 | |
| 23 | ALLIANCEBERNSTEIN L.P. | $59.2M | 455K | ▲+740% Added · +401K sh | Q1 2026 | |
| 24 | Magnetar Financial LLC | $76.0M | 427K | ▲78× Added · +422K sh | Q1 2026 | |
| 25 | AQR Arbitrage LLC | $73.9M | 417K | ▲New +417K sh | Q1 2026 |
Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Jun 10, 2026 | LANE WENDY E | Director | Disposed to issuer (D) | 3K | $469K |
| Jun 10, 2026 | LANE WENDY E | Director | Disposed to issuer (D) | 1K | — |
| Jun 10, 2026 | Brennan Michelle | Director | Disposed to issuer (D) | 9K | $1.7M |
| Jun 10, 2026 | Brennan Michelle | Director | Disposed to issuer (D) | 1K | — |
| Jun 10, 2026 | Politan Capital Management LP | Insider | Other (J) | 143K | — |
| Jun 10, 2026 | Politan Capital Management LP | Insider | Other (J) | 131K | — |
| Jun 10, 2026 | Politan Capital Management LP | Insider | Disposed to issuer (D) | 4.6M | $826.4M |
| Jun 10, 2026 | Politan Capital Management LP | Insider | Disposed to issuer (D) | 1K | — |
| Jun 10, 2026 | Sampath Anand | EVP, Operations | Disposed to issuer (D) | 34K | $6.1M |
| Jun 10, 2026 | Sampath Anand | EVP, Operations | Disposed to issuer (D) | 2K | — |
| Jun 10, 2026 | Sampath Anand | EVP, Operations | Disposed to issuer (D) | 5K | — |
| Jun 10, 2026 | Sampath Anand | EVP, Operations | Disposed to issuer (D) | 5K | — |
| Company | Co-held by | Combined value |
|---|---|---|
| META PLATFORMS INC-CLASS AMETA | 148 funds | $29.1B |
| MICROSOFT CORPMSFT | 147 funds | $62.1B |
| AMAZON.COM INCAMZN | 147 funds | $46.1B |
| ALPHABET INC-CL AGOOGL | 147 funds | $40.8B |
| NVIDIA CORPNVDA | 146 funds | $86.7B |
| APPLE INCAAPL | 146 funds | $72.0B |
| ELI LILLY & COLLY | 146 funds | $16.2B |
| BROADCOM INCAVGO | 144 funds | $31.8B |
| BOSTON SCIENTIFIC CORPBSX | 144 funds | $3.4B |
| TESLA INCTSLA | 143 funds | $19.6B |
| MICRON TECHNOLOGY INCMU | 142 funds | $11.2B |
| BANK OF AMERICA CORPBAC | 142 funds | $6.6B |
Ranked by how many of MASI's institutional holders also hold each name, a cross-fund conviction signal. Via the MCP server (ticker.co_held).
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for MASI. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes. Every panel above is one call to the Arkolith API & MCP server.