Last year, the two companies signed a 10-year search
deal; earlier this year, Microsoft’s Bing began powering search engine results
for Yahoo search properties in the U.S. and Canada.
With the Yahoo paid search
expansion, Microsoft’s adCenter now reaches a total of 163 million unique
users, and 33.8% of all U.S. search queries.
Yahoo said it hopes to also
transition to using Microsoft’s mobile search ad platform by the end of
October, and expects international search to transition to Microsoft by early