Amphenol Corporation

The full register, from 13F filings

The Register tab above is hand research: a dozen holders, each traced to the filing it came from. This asks the same question of the whole market for the quarter ended 31-mar-2026, where 2,090 managers reported a position. Broad where the research is deep, and shallow in the ways a 13F always is.

Built from 13F filings, which report US listed, long, US custodied positions only. A register from this source is a floor rather than a level: a holder's true position can be far larger, as BlackRock's ASML stake shows at 1.28m shares in a 13F against 26.3m in its 13G/A. Holdings held through derivatives, outside US custody, or below a manager's reporting obligation do not appear. Where a holder is marked as a family, its total sums several separate filing entities and describes something no single filing describes; the constituent entities and their share counts are listed so the total can be checked. That roll-up can legitimately exceed the family's own Schedule 13G, because a 13G is filed by one legal entity: Vanguard reports Alphabet through ten advisory entities, and The Vanguard Group Inc itself reported zero after its January 2026 disaggregation.

What a reader needs to know to read these numbers

• Amphenol does not file Form 13F. Its EDGAR filing history under CIK 0000820313 (submissions JSON, checked 17 August 2026) contains 10-K, 10-Q, DEF 14A, Forms 3/4/5, Schedule 13G and 13G/A filings but no 13F-HR or 13F-NT of any vintage, consistent with it being an operating company rather than an institutional investment manager.
• Amphenol's holdings list is empty and that is the sourced finding, not a gap. The FY2025 Form 10-K (period ended 31 December 2025, filed 11 February 2026) and the Q2 FY2026 Form 10-Q (period ended 30 June 2026, filed 31 July 2026) were fetched and searched in full for 'equity method', 'equity investment', 'non-marketable', 'measurement alternative', 'joint venture', 'affiliate', 'unconsolidated', 'cost method' and 'equity securities': neither filing discloses an equity-method investment, a non-marketable equity security, or a named minority stake in another company. The one 'equity securities' hit in the 10-K is a pension-plan asset fair-value table (Level 1/2/3 breakdown of plan assets), which is an index-fund style holding excluded by the brief, not a strategic corporate stake.
• Amphenol's growth model is outright acquisition, not minority stakes: the most recent major deal is the acquisition of CommScope's Connectivity and Cable Solutions (CCS) business for approximately $10.5 billion, reported in 2026 press and SEC coverage. Wholly owned acquisitions are excluded from holdings by the brief.
• The 10-K discloses 'noncontrolling interests' and 'redeemable noncontrolling interests', but these run the opposite direction from a holding: they are third parties' minority stakes in Amphenol's own consolidated subsidiaries, not Amphenol's stake in someone else. Not recorded as a holding.
• Amphenol has a single class of common stock, Class A Common Stock, one vote per share, $0.001 par value; no Class B is authorized or outstanding (searched the FY2025 10-K, no hits for 'Class B'). There is no dual-class structure and no founder-control block. Insider ownership is small: CEO and Chairman-elect R. Adam Norwitt holds 8,219,557 shares (0.67 percent), and all 16 current executive officers and directors as a group hold 17,469,159 shares (1.42 percent, stated directly by the proxy). This is not a control position.
• Vanguard realignment, recorded rather than resolved. On 26 March 2026 The Vanguard Group filed a Schedule 13G/A on Amphenol disclosing an internal realignment: it no longer beneficially owns any Amphenol shares directly. Going forward, shares previously attributed to The Vanguard Group are reported on a disaggregated basis by two wholly owned U.S. investment-adviser affiliates, Vanguard Capital Management and Vanguard Portfolio Management (per Amphenol's 8 April 2026 DEF 14A, footnote 2 to the beneficial-owners table). Consistent with this, Vanguard Group Inc (CIK 0000102909) filed Form 13F-NT (a notice, with no holdings data) for the quarters ended 31 March 2026 and 30 June 2026, rather than 13F-HR. The register above uses Vanguard Capital Management LLC's own Schedule 13G (CIK 0002100119, filed 29 April 2026, event date 31 March 2026): 91,856,807 shares, 7.47 percent of class. This almost certainly understates the combined Vanguard family position because it excludes whatever Vanguard Portfolio Management separately holds, which could not be sourced. For comparison, Vanguard Group Inc's last full 13F-HR before the split (period 31 December 2025, filed 29 January 2026) reported 126,553,498 shares, 10.264 percent against the denominator used here.
• Percent denominators, not mixed. All 30 June 2026 Form 13F rows and the Vanguard Capital Management Schedule 13G row use 1,232,983,457 shares outstanding as of 28 July 2026 (Q2 FY2026 10-Q cover page). The insider rows use 1,229,430,709 shares outstanding as of 23 March 2026, the record date the proxy itself uses; do not mix the two.
• All 30 June 2026 13F values are the managers' own reported market values at that date. BlackRock's row implies a price of roughly $176.32 per share on 30 June 2026, the consistent quarter-end mark across the 13F rows here.
• Market capitalisation of $206.04 billion is the figure published on stockanalysis.com as of 14 August 2026 (close price $167.11). Cross-check: 1,232,983,457 shares at $167.11 implies approximately $206.06 billion, consistent to within rounding.
• The 'All executive officers and directors of the Company as a group (16 persons)' row (17,469,159 shares, 1.42 percent) contains the four individually listed insider rows above plus 9 other individually named directors/officers in the proxy (each holding fewer than 600,000 shares) and unnamed others; it must not be added to the individual rows.