With AI capital expenditures exploding to $1 trillion this year, the financing mix is beginning to shift from free cash flow and debt toward equity.Among the megacap hyperscalers, Alphabet has been the most aggressive in tapping the equity market (read report), while Microsoft, Amazon, and Meta continue to rely primarily on cash flow, debt, leases, and structured financing.Intel is set to join the broader AI infrastructure complex in tapping equity markets, announcing in a press release Monday morning that it plans a $15 billion underwritten public offering of common stock to bolster its balance sheet and help fund investments across AI compute, custom silicon, advanced packaging, external foundry services, and the emerging physical-AI economy.More color:Intel intends to use the net proceeds from the offering for general corporate purposes, which may include, but are not limited to, capital expenditures and working capital. The offering is intended to further enable Intel to pursue the growth opportunities ahead while maintaining a strong balance sheet and its commitment to an investment-grade rating. Worth noting: An underwritten public offering is not the same as an ATM program that allows shares to be sold "from time to time." Today's announcement is merely a proposed offering, but the shares have not yet been priced or sold. Pricing and closing will follow, subject to market conditions.Underwriters are expected to receive a 30-day option to purchase up to $2.25 billion of additional shares, potentially increasing the offering to $17.25 billion. JPMorgan, Goldman Sachs, Morgan Stanley, and Citigroup are acting as joint bookrunners.The proposed offering comes as Intel shares have risen more than 175% year to date through Friday's close. Shares slipped 3% on the news earlier Monday.Next year, Goldman expects hyperscalers' capital expenditures to top $1.4 trillion.Hyperscalers have a free-cash-flow problem..."You are here" - only MSFT has positive free cash flow now pic.twitter.com/YqoHQYOIAb