Google matches the greater of something like 100% of $3000 - or - 50% of the max employee contribution.
A 100% match from Microsoft would mean an annual 2015 contribution of $36,000 ($18,000 employee + $18,000 employer match) versus $27,000 maximum ($18,000 employee + $9,000 employer match) from Google. That's a $9000 difference.
EDIT: Looks like the article is incorrect. Correct numbers are 50%, as stated in parent comment.
A 100% match from Microsoft would mean an annual 2015 contribution of $36,000 ($18,000 employee + $18,000 employer match) versus $27,000 maximum ($18,000 employee + $9,000 employer match) from Google. That's a $9000 difference.
EDIT: Looks like the article is incorrect. Correct numbers are 50%, as stated in parent comment.