Apple may be worth one and a half Googles now, but the world’s most valuable company needs its relationship with the world’s largest search engine to keep clicking. Such was evident Monday when Apple

Apple wants to join the antitrust case against Google, and it has explained why it doesn't want to create its own rival search engine.

Apple has asked to participate in Google's upcoming U.S. antitrust trial over online search, saying it cannot rely on Google to defend revenue-sharing agreements that send the iPhone maker billions of dollars each year for making Google the default search engine on its Safari browser.