Conversation so far:
What is Steve Ballmer's position on Google?
In 2013, Ballmer said that Google was a monopoly that should be pressured from market competition authorities
Does Steve Ballmer work at Google?
Ballmer vowed to kill Google, Lucovsky reports.
What is Steve Ballmer's connection to Google?
In 2005, while Ballmer was the CEO of Microsoft, Microsoft sued Google.

Question: What was the reason for the lawsuit?
Self-contained rewrite: What was Steve Ballmer's reason for the lawsuit against Google?