Among active 13F managers last quarter, 6 opened and 21 added, while 18 reduced; the largest holder to move was TD Asset Management Inc (−21%). Over the last 180 days, 3 insiders sold and none bought, a net -$421K in open-market trades.
The legs disagree, or only one of them leans.
182 tracked 13F filers disclose a position in AMPH as of the latest SEC 13F filings, a combined $561.8M in reported value. 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.
| # | Fund | Shares | Position value | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 5.2M | $105.4M | ▼−3.6% Reduced · −196K sh | Q2 2026 | |
| 2 | Dimensional Fund Advisors LP | 2.0M | $39.7M | ▲+13% Added · +228K sh | Q1 2026 | |
| 3 | State Street Corp | 1.6M | $33.1M | ▲+2.1% Added · +35K sh | Q2 2026 | |
| 4 | TD Asset Management Inc | 1.5M | $30.2M | ▼−21% Reduced · −422K sh | Q1 2026 | |
| 5 | Vanguard Capital Management LLC | 1.5M | $29.9M | ▼−4.0% Reduced · −62K sh | Q2 2026 | |
| 6 | Marshall Wace, LLP | 1.0M | $20.1M | ▼−17% Reduced · −212K sh | Q1 2026 | |
| 7 | American Century Companies Inc | 1.0M | $19.9M | ▲+53% Added · +352K sh | Q1 2026 | |
| 8 | Geode Capital Management, LLC | 970K | $19.6M | ▼−0.7% Reduced · −7K sh | Q2 2026 | |
| 9 | Fuller & Thaler Asset Management, Inc. | 949K | $19.2M | ▼−32% Reduced · −446K sh | Q2 2026 | |
| 10 | Boston Trust Walden Corp | 945K | $18.5M | ▼−13% Reduced · −142K sh | Q1 2026 | |
| 11 | Vanguard Portfolio Management LLC | 810K | $16.3M | ▲+2.8% Added · +22K sh | Q2 2026 | |
| 12 | D. E. Shaw & Co., Inc. | 666K | $13.0M | ▲+19% Added · +108K sh | Q1 2026 | |
| 13 | Renaissance Technologies LLC | 554K | $10.9M | ▲+1.7% Added · +9K sh | Q1 2026 | |
| 14 | Systematic Financial Management LP | 437K | $8.8M | ▼−3.4% Reduced · −16K sh | Q2 2026 | |
| 15 | Morgan Stanley | 420K | $8.2M | ▼−29% Reduced · −171K sh | Q1 2026 | |
| 16 | UBS Group AG | 420K | $8.2M | ▲+64% Added · +164K sh | Q1 2026 | |
| 17 | Denali Advisors LLC | 376K | $7.6M | ▲+41% Added · +110K sh | Q2 2026 | |
| 18 | Northern Trust Corp | 372K | $7.3M | ▲+0.2% Added · +888 sh | Q1 2026 | |
| 19 | Millennium Management LLC | 371K | $7.3M | ▲+28% Added · +81K sh | Q1 2026 | |
| 20 | Bridge City Capital, LLC | 339K | $6.8M | ▲+1.1% Added · +4K sh | Q2 2026 | |
| 21 | Goldman Sachs Group Inc | 329K | $6.5M | ▼−41% Reduced · −227K sh | Q1 2026 | |
| 22 | Arrowstreet Capital, Limited Partnership | 325K | $6.4M | ▼−42% Reduced · −234K sh | Q1 2026 | |
| 23 | Charles Schwab Investment Management Inc | 321K | $6.3M | ▼−8.4% Reduced · −30K sh | Q1 2026 | |
| 24 | Bridgeway Capital Management, LLC | 299K | $6.0M | ▼−9.5% Reduced · −32K sh | Q2 2026 | |
| 25 | Victory Capital Management Inc | 250K | $4.9M | ▼−18% Reduced · −56K 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.
Last quarter, 6 funds opened a new position in AMPH and 21 added to an existing one, while 18 reduced. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).
| Company | Co-held by | Their position there |
|---|---|---|
| Microsoft CorpMSFT | 96 funds | $178.0B |
| Nvidia CorpNVDA | 95 funds | $281.1B |
| Amazon.com IncAMZN | 95 funds | $136.1B |
| Eli Lilly & CoLLY | 95 funds | $58.7B |
| Meta Platforms Inc-Class AMETA | 94 funds | $73.3B |
| JPMorgan Chase & CoJPM | 93 funds | $41.4B |
| Visa Inc-Class A SharesV | 92 funds | $41.3B |
| Abbvie IncABBV | 92 funds | $24.6B |
| Apple IncAAPL | 91 funds | $200.6B |
| Lam Research CorpLRCX | 91 funds | $34.4B |
| Costco Wholesale CorpCOST | 91 funds | $25.1B |
| Alphabet Inc-CL AGOOGL | 90 funds | $120.7B |
Ranked by how many of AMPH's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in AMPH.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Sep 2, 2026 | Zhou Rong | SENIOR EVP, PRODUCTION CENTER | Sell (S) | 3K | $75K |
| Aug 11, 2026 | Prins Richard K | Director | Sell (S) | 8K | $162K |
| Aug 7, 2026 | Peters William J | CFO, EVP & TREASURER, Director | Sell (S) | 8K | $184K |
| Dec 17, 2025 | Zhou Rong | SENIOR EVP, PRODUCTION CENTER | Sell (S) | 10K | $256K |
| Dec 12, 2025 | Petersen Floyd F. | Director | Sell (S) | 2K | $63K |
| Dec 11, 2025 | Petersen Floyd F. | Director | Sell (S) | 2K | $45K |
| Nov 25, 2025 | Prins Richard K | Director | Sell (S) | 4K | $113K |
| Nov 13, 2025 | Petersen Floyd F. | Director | Sell (S) | 17K | $442K |
| Nov 3, 2025 | Petersen Floyd F. | Director | Sell (S) | 500 | $13K |
| Oct 1, 2025 | Petersen Floyd F. | Director | Sell (S) | 500 | $14K |
| Sep 2, 2025 | Petersen Floyd F. | Director | Sell (S) | 500 | $15K |
| Aug 1, 2025 | Petersen Floyd F. | Director | Sell (S) | 500 | $10K |
Where institutional funds (13F), corporate insiders (Form 4) and US House members (STOCK Act) are buying or selling the same name in the same window. Green is buying, red is selling.
Insiders and Congress: last 180 days. Funds: latest 13F, top 100 holders incl. passive
| Source | Buying | Selling | Net |
|---|---|---|---|
13F funds Top 100 holders by value, passive included; the hero counts active managers only | 40 | 41 | – |
Insiders Form 4 open-market | 0 | 3 | -$421K |
US House STOCK Act trades | 0 | 0 | $0 |
Capital Rotation reports where institutional capital disclosed rotating, as of the latest public SEC 13F filings. It is data, not investment advice, a recommendation, or a prediction. Filings lag about 45 days and cover long US equity positions only. Past disclosed flows do not indicate future prices. Do your own research; consult a licensed advisor.
| Class | 13F holders | Value held |
|---|---|---|
| AMPHthis pagecs | 182 funds | $561.8M |
| AMPH 2 03/15/29Sovereign/Corporate | 37 funds | $345.7M |
Same issuer, multiple share classes. The consensus leaderboards count this company once across all classes; this is the per-class detail.
Connected entities for AMPH
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/AMPH/capital-change-brief"
Use Arkolith's capital_change_brief for AMPH. Tell me what changed, whether insider activity corroborates it, and cite the SEC evidence.
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for AMPH. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.