램리서치코퍼레이션
MX ˙ BMV ˙ US5128071082
SecurityMX:LRCX / Lam Research Corporation
InstitutionCookson Peirce & Co Inc
Latest Disclosed Ownership89,986 shares
Latest Disclosed Value $ 19,226,315
Cookson Peirce & Co Inc reports 19.80% increase in ownership of LRCX / Lam Research Corporation

On April 30, 2026 - Cookson Peirce & Co Inc filed a 13F-HR form disclosing ownership of 89,986 shares of Lam Research Corporation (MX:LRCX) valued at $19,226,315 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 75,113 shares of Lam Research Corporation. This represents a change in shares of 19.80% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-04-30 2026-03-31 13F LAM RESEARCH COM NEW 512807306 89,986 14,873 19.80 19,226 49.54 0.8139
2026-02-11 2025-12-31 13F LAM RESEARCH COM NEW 512807306 75,113 64,603 614.68 12,858 813.79 0.5326
2025-11-06 2025-09-30 13F LAM RESEARCH COM NEW 512807306 10,510 41 0.39 1,407 38.08 0.0577
2025-07-30 2025-06-30 13F LAM RESEARCH COM NEW 512807306 10,469 2,119 25.38 1,019 67.87 0.0448
2025-05-13 2025-03-31 13F LAM RESEARCH COM NEW 512807306 8,350 8,350 607 0.0305
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.