Until a year or two ago, big tech firms like Google had relatively simple balance sheets, stuffed with cash that covered any debt several times over. Nowadays, thanks to massive AI spending, Google and others are adopting techniques long used on Wall Street to expand their business without taking on all the risk themselves.

Google, for example, disclosed last week that it had agreed to cover as much as $44 billion worth of lease payments on data centers owned by others, if the tenant defaults. That figure, which has risen from $6.5 billion as of the end of September, reflects Google’s efforts to supply Anthropic and others with its alternative to Nvidia’s AI chips.