A bond sale tied to Microsoft’s data center expansion is on track to reach roughly $4 billion, up from an initial $3.9 billion target, underscoring sustained investor demand for debt linked to AI infrastructure. The deal follows a similar transaction in April 2026, when a Blackstone-backed debut bond offering by QTS for a Microsoft data center in Phoenix attracted about $12.5 billion in demand, more than three times the size of that sale. The financing push comes as Microsoft, Amazon, Meta and Alphabet plan hundreds of billions of dollars in 2026 capital expenditures, with Microsoft alone guiding toward about $190 billion in spending, much of it directed to data centers, networking equipment and other hardware needed to run AI systems. The structure gives fixed-income investors exposure to the AI buildout without taking on equity-market volatility, helping position AI infrastructure debt as a distinct asset class.