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/AMPX/capital-change-brief"
Use Arkolith's capital_change_brief for AMPX. 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. | $155.5M | 9.2M | ▲+4.5% Added · +402K sh | Q1 2026 | |
| 2 | VANGUARD CAPITAL MANAGEMENT LLC | $82.8M | 4.9M | ▲New +4.9M sh | Q1 2026 | |
| 3 | JANE STREET GROUP, LLC | $70.1M | 4.2M | ▲19× Added · +3.9M sh | Q1 2026 | |
| 4 | TWO SIGMA INVESTMENTS, LP | $59.1M | 3.5M | ▲+144% Added · +2.1M sh | Q1 2026 | |
| 5 | MORGAN STANLEY | $53.3M | 3.2M | ▲+13% Added · +352K sh | Q1 2026 | |
| 6 | GEODE CAPITAL MANAGEMENT, LLC | $47.5M | 2.8M | ▲+5.1% Added · +136K sh | Q1 2026 | |
| 7 | STATE STREET CORP | $45.7M | 2.7M | ▲+6.2% Added · +159K sh | Q1 2026 | |
| 8 | UBS Group AG | $39.0M | 2.3M | ▲+10% Added · +213K sh | Q1 2026 | |
| 9 | GOLDMAN SACHS GROUP INC | $37.5M | 2.2M | ▲+1.4% Added · +31K sh | Q1 2026 | |
| 10 | MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $34.1M | 2.0M | ▲New +2.0M sh | Q1 2026 | |
| 11 | PRICE T ROWE ASSOCIATES INC /MD/ | $32.0M | 1.9M | ▲24× Added · +1.8M sh | Q1 2026 | |
| 12 | Baird Financial Group, Inc. | $26.7M | 1.6M | ▲+105% Added · +812K sh | Q1 2026 | |
| 13 | CITADEL ADVISORS LLC | $24.3M | 1.4M | ▲+216% Added · +984K sh | Q1 2026 | |
| 14 | NORGES BANK | $10.3M | 1.3M | ▲New +1.3M sh | Q4 2025 | |
| 15 | MARSHALL WACE, LLP | $20.7M | 1.2M | ▲New +1.2M sh | Q1 2026 | |
| 16 | Qube Research & Technologies Ltd | $20.7M | 1.2M | ▲+40% Added · +353K sh | Q1 2026 | |
| 17 | JPMORGAN CHASE & CO | $17.9M | 1.2M | ▲15× Added · +1.1M sh | Q1 2026 | |
| 18 | WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC | $19.7M | 1.2M | ▲+19% Added · +185K sh | Q1 2026 | |
| 19 | D. E. Shaw & Co., Inc. | $18.1M | 1.1M | ▲New +1.1M sh | Q1 2026 | |
| 20 | VANGUARD PORTFOLIO MANAGEMENT LLC | $18.1M | 1.1M | ▲New +1.1M sh | Q1 2026 | |
| 21 | BARCLAYS PLC | $17.8M | 1.1M | ▲+124% Added · +585K sh | Q1 2026 | |
| 22 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $17.5M | 1.0M | ▲+0.2% Added · +3K sh | Q1 2026 | |
| 23 | MILLENNIUM MANAGEMENT LLC | $17.5M | 1.0M | ▼−4.6% Reduced · −50K sh | Q1 2026 | |
| 24 | NORTHERN TRUST CORP | $17.2M | 1.0M | ▲+6.2% Added · +59K sh | Q1 2026 | |
| 25 | Hood River Capital Management LLC | $16.0M | 949K | ▲+17% Added · +139K 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 15, 2026 | DIXON DONALD R | Director | Sell (S) | 85K | $1.5M |
| Jun 12, 2026 | DIXON DONALD R | Director | Grant (A) | 10K | $0 |
| Jun 12, 2026 | BAYLESS KATHLEEN A | Director | Grant (A) | 10K | $0 |
| Jun 12, 2026 | SATTERTHWAITE LIVINGSTON | Director | Grant (A) | 10K | $0 |
| Jun 12, 2026 | Chu Steven | Director | Grant (A) | 10K | $0 |
| Jun 9, 2026 | DIXON DONALD R | Director | Sell (S) | 40K | $765K |
| Jun 4, 2026 | Stepien Thomas M | Chief Executive Officer, Director | Gift (G) | 30K | $0 |
| Jun 4, 2026 | Stepien Thomas M | Chief Executive Officer, Director | Gift (G) | 37K | $0 |
| Jun 4, 2026 | Stepien Thomas M | Chief Executive Officer, Director | Gift (G) | 37K | $0 |
| Jun 4, 2026 | Stepien Thomas M | Chief Executive Officer, Director | Sell (S) | 2K | $42K |
| May 27, 2026 | Stepien Thomas M | Chief Executive Officer, Director | Sell (S) | 4K | $75K |
| May 27, 2026 | Sun Kang | Director | Sell (S) | 356 | $6K |
| Company | Co-held by | Combined value |
|---|---|---|
| MICROSOFT CORPMSFT | 72 funds | $31.1B |
| ALPHABET INC-CL AGOOGL | 72 funds | $20.1B |
| NVIDIA CORPNVDA | 71 funds | $44.6B |
| APPLE INCAAPL | 70 funds | $35.6B |
| AMAZON.COM INCAMZN | 70 funds | $23.7B |
| META PLATFORMS INC-CLASS AMETA | 70 funds | $13.8B |
| ALPHABET INC-CL CGOOG | 69 funds | $13.3B |
| VISA INC-CLASS A SHARESV | 69 funds | $7.5B |
| NETFLIX INCNFLX | 69 funds | $4.6B |
| JPMORGAN CHASE & COJPM | 68 funds | $9.4B |
| TESLA INCTSLA | 68 funds | $9.4B |
| ELI LILLY & COLLY | 68 funds | $8.9B |
Ranked by how many of AMPX'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 AMPX. 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.