The hidden debt of the United States' top five tech companies has soared to $1.65 trillion, according to a study by Nikkei. This represents an eightfold increase over four years, driven by a surge in artificial intelligence investments. The study highlights that this hidden debt surpasses the companies' recorded liabilities, complicating risk assessments for investors. Nikkei's analysis of financial statements from Alphabet, Microsoft, Amazon, Meta, and Oracle reveals that Meta's off-balance-sheet debt is particularly significant, amounting to approximately $420 billion, nearly three times its reported debt.