Lam Research 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 2,579 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

• Share count basis: Lam effected a ten-for-one stock split of its common stock on 2 October 2024 (per the FY2025 10-K, filed 11 Aug 2025), not in 2025 as might be assumed. Every share figure in this file, including all 13F and proxy data (all dated after October 2024), is already on the post-split basis. shares_outstanding (1,251,321,000) is the FY2026 10-K cover-page figure, stated as of 4 August 2026, filed 7 August 2026. The FY2026 10-K balance sheet separately shows 1,251,278,000 shares issued and outstanding as of 28 June 2026 (fiscal year end), consistent with the cover-page figure.
• Holdings is empty and that is the sourced finding, not a gap. The FY2026 10-K (period ended 28 June 2026, filed 7 August 2026) was fetched and searched in full for 'equity method', 'equity investment', 'non-marketable', 'measurement alternative', 'unrealized gain', 'strategic investment', 'joint venture' and 'equity securities'. The only relevant hits describe fluctuations in the fair market value of the Company's equity investments within the 'other, net' line of the income statement, and the balance sheet note states explicitly that as of 28 June 2026 and 29 June 2025 'the fair value, and associated unrealized loss positions, if any, of mutual funds and equity investments were not material.' No investee is named and no dollar figure is disclosed for any single position. All 'joint venture' hits describe Lam's customers establishing joint ventures with each other, not any joint venture Lam itself holds an interest in. Lam does not file Form 13F: the complete EDGAR submissions history for CIK 0000707549 (checked 17 August 2026) contains no 13F-HR filing of any vintage, consistent with Lam not acting as an institutional investment manager.
• The only investing activity visible on the face of the financial statements is purchases and sales of investments (mutual funds, equity and debt securities held for cash management) within investing cash flows; these are not broken out by counterparty and are treated as treasury-style holdings excluded by the brief, not as strategic stakes.
• Lam has a single class of common stock, $0.001 par value, per the FY2026 10-K cover page and balance sheet. There is no dual-class structure and no founder-control block; CEO Timothy Archer's 1,481,175 shares are about 0.12 percent of the company with no enhanced voting rights.
• BlackRock disagreement, recorded rather than resolved. The register uses BlackRock, Inc.'s own Form 13F-HR for the quarter ended 30 June 2026 (CIK 0002012383): 132,830,776 shares, 10.615 percent. Lam's 24 September 2025 proxy statement instead reports BlackRock at 117,779,780 shares, 9.34 percent, sourced to a Schedule 13G/A BlackRock filed 25 January 2024, roughly 18 months stale relative to the proxy's own record date and over two years stale relative to the 13F used here.
• Vanguard disagreement, recorded rather than resolved. The register uses The Vanguard Group's own Form 13F-HR for the quarter ended 31 December 2025 (CIK 0000102909): 131,185,330 shares, 10.505 percent. Lam's 24 September 2025 proxy statement instead reports Vanguard at 129,149,892 shares, 10.24 percent, as of an unstated 'most recent ownership report' date, which predates the 13F figure used here. Vanguard filed Form 13F-NT (notice, no holdings) under CIK 0000102909 for the quarters ended 31 March 2026 and 30 June 2026, so no more recent Vanguard 13F-HR position exists under this CIK; a Vanguard-affiliated reporting entity may hold the shares reported for those quarters but was not identified within the time budget.
• Percentages for the six institutional 13F rows measured as of 30 June 2026 use 1,251,321,000 shares outstanding (10-K cover page, as of 4 August 2026, the closest available count after that date). The Vanguard row (13F as of 31 December 2025) uses 1,248,771,000 shares outstanding (10-Q cover page, as of 27 January 2026, the closest available count). The three proxy-sourced insider rows use 1,261,032,300 shares outstanding as of 5 September 2025, which is the denominator the proxy itself states. All of these counts postdate the October 2024 split, so no basis mixing occurs, but they are three slightly different counts and each row states which one it used.
• The seven listed 13F filers imply somewhat different per-share valuations at their respective quarter ends: about $433 per share for BlackRock, State Street, Geode, FMR and Morgan Stanley (all as of 30 June 2026), but about $411 per share for JPMorgan's common-stock lines on the same date. This is the value each manager itself reported and was not adjusted.
• Insider rows overlap. The 'All current directors and executive officers as a group (17 people)' row (3,971,889 shares, 0.315 percent) contains the individually listed Timothy Archer and Douglas Bettinger rows and must not be added to them.
• Market capitalisation of $415.89 billion is the figure published on the source page as of 14 August 2026.