I’m think many news sites are getting the MS = $15B number wrong.Given the first announced foundry customer deal was Microsoft, worth $15B, the other 5 customers must be worth $0 ?
If you google for “Intel 18A foundry customers”, you get a base $10B going to $15B after MS was added, around the February timeframe. (Implying MS business is worth $5B).

Intel Foundry Wins "Magnificent Seven" Customer as Backlog Rockets Past $15 Billion | The Motley Fool
Microsoft will use Intel's manufacturing services for a next-generation chip.

(And just before the MS announcement):
Intel's Foundry Business Has $10 Billion Locked In, Who are the Four Customers?
The biggest shift in Intel's (NASDAQ: INTC) strategy over the past few years under CEO Pat Gelsinger has been opening up its manufacturing operations to third parties. This isn't the first time Intel has attempted to build its own foundry business -- it tried and failed for about five years...
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