In May, CoreWeave, a provider of cloud computing services for A.I. companies, raised $1.1 billion, followed by $7.5 billion in debt, valuing it at $19 billion. Scale AI, a provider of data for A.I. companies, raised $1 billion, valuing it at $13.8 billion. And xAI, founded by Elon Musk, raised $6 billion, valuing it at $24 billion.

Such financing rounds have boosted the industry’s overall deal-making by dollar amount and number of deals, said Kyle Stanford, a research analyst at PitchBook.

“It’s not declining anymore,” he said. “The bottom has already fallen out.”

The activity has prompted some venture capital investors to change their message. Last year, Tom Loverro, an investor at IVP, predicted a “mass extinction event” for start-ups and encouraged them to cut costs. Last week, he declared that era over and christened this time the “Great Reawakening,” encouraging companies to “pour gas” on growth, particularly around artificial intelligence.

“The AI train is leaving the station & you need to be on it,” he wrote on X.

The start-up downturn began in early 2022 as many money-losing companies struggled to grow as quickly as they did in the pandemic. Rising interest rates also pushed investors to chase less risky investments. To make up for dwindling funding, start-ups slashed staff and scaled back their ambitions.

Then in late 2022, OpenAI, a San Francisco A.I. lab, kicked off a new boom with the release of its ChatGPT chatbot. Excitement around generative A.I. technology, which can produce text, images and videos, set off a frenzy of start-up creation and funding.