All three major US stock indexes were in the red around midday trading Friday, with the Nasdaq Composite down 1.7%, after President Donald Trump threatened to impose "massive" tariff increases on China.

In company news, Nvidia's (NVDA) artificial intelligence processors and other shipments from the US are being subject to stringent checks in China, as the country mobilizes customs officers to implement tighter controls on chip imports, the Financial Times reported Friday, citing three people with knowledge of the matter. Separately, the US Senate passed a bipartisan amendment Thursday that would require Nvidia and Advanced Micro Devices (AMD) to prioritize US companies over Chinese buyers. Nvidia shares were down 1.3% around noon, while AMD shares were down 5.3%.

Applied Digital (APLD) reported a fiscal Q1 adjusted net loss late Thursday of $0.03 per diluted share, widening from a loss of $0.01 a year earlier but better than the estimate of four analysts surveyed by FactSet calling for a loss of $0.16. Fiscal Q1 revenue was $64.2 million, up from $34.8 million and above the FactSet consensus estimate of $50 million. Applied Digital shares were up nearly 20%.

Johnson & Johnson (JNJ) is in talks to acquire Protagonist Therapeutics (PTGX), The Wall Street Journal reported Friday, citing people familiar with the matter. Johnson & Johnson shares were up 0.1%, while those of Protagonist were up more than 35%.

Mosaic (MOS) said Friday its preliminary Q3 phosphate production fell short of expectations due to "unexpected mechanical issues" at its Riverview sulfuric acid plant in and utility interruptions at Bartow in September, both in Florida. Mosaic shares were down 7.6%.

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