Applied Materials Inc. suffered the worst single-day stock decline in five years after giving a disappointing sales and profit forecast, renewing concerns that the US trade dispute with China is weighing on demand.

Shares of Applied Materials Inc (NASDAQ: AMAT) tanked despite upbeat fiscal Q3 results. BofA downgraded, Goldman Sachs reiterated buy, Needham kept buy.

Applied Materials, Inc. delivered record Q3 results, with strong revenue, EPS, margins, and robust cash flow, highlighting the current strength in the semiconductor cycle. Q4 guidance signals a potential slowdown: projected revenue and EPS are both down year-over-year, with Semiconductor Systems orders showing notable weakness.

Beijing E-Town Semiconductor Technologies , a semiconductor equipment firm backed by Beijing's government, on Wednesday said it has sued U.S. chip equipment supplier Applied Materials over alleged trade secrets infringement.

Applied Materials (AMAT) stock falls after the company issued guidance that fell short of Wall Street's expectations. Warren Buffett's Berkshire Hathaway (BRK-B, BRK-A) added to its stakes in homebuilder stocks Lennar (LEN) and DR Horton (DHI).

Shares of technology companies declined as a tepid outlook from one major chip-equipment manufacturer cast a pall on the semiconductor sub-sector. Shares of Applied Materials plunged after the maker of semiconductor manufacturing equipment forecast growth short of Wall Street expectations.

CNBC's Kristina Partisinevelos joins 'Squawk on the Street' to discuss the latest earnings from Applied Materials.

Bank of America downgraded Applied Materials to Neutral from Buy and cut its price objective to $180 from $190, citing a weaker-than-expected fiscal fourth-quarter outlook and growing exposure to sluggish chip equipment segments.