The Globe and Mail reports in its Friday edition that the cost of insuring against the risk of potential U.S. tech defaults has hit record levels, in the latest sign of credit stress building in the so-called AI trade, especially for data-centre operators. A Reuters dispatch to The Globe says that although shares in companies driving the artificial-intelligence boom are still among the biggest gainers on global equity markets this year, many have fallen sharply in the past few weeks, as investors reassess the cost of capital against a backdrop of rising interest rates and inflation. There are also doubts among some investors and analysts about when, and in some cases, if, the billions of dollars pouring into data centres, computer power and other infrastructure will pay off. Demand for AI-linked credit default swaps (CDS), a form of insurance against default that gained prominence during the 2008 financial crisis, has soared, even for heavyweights like Apple, Amazon and Microsoft. For some of their more heavily indebted competitors, suppliers and customers the cost of CDS has risen even faster. A CDS is a derivative that provides protection against the risk that a bond issuer fails to meet its debt obligations.