Disable "Spotlight Suggestions" and "Bing Web Searches" in System Preferences > Spotlight > Search Results.
Safari also has a "Spotlight Suggestions" setting that is separate from Spotlight's "Spotlight Suggestions". This uses the same mechanism as Spotlight, and if left enabled, Safari will send a copy of all search queries to Apple.
You'd be forgiven for thinking that you'd already disabled "Spotlight Suggestions", but you'll also need to uncheck "Include Spotlight Suggestions" in Safari > Preferences > Search.
Alternatively, you can apply the changes automatically using fix-macosx.py.
Spotlight isn't the only Mac OS X Yosemite feature that unnecessarily phones home; a myriad of system and user processes are sending data to Apple in a default configuration, and we want to fix those, too.
Yosemite Phone Home is a collaborative project to identify additional data that collected by Apple and other third parties. This work is powered by Net-Monitor, our open-source toolkit for auditing phone home behavior system-wide.
If you've upgraded to Mac OS X Yosemite (10.10) and you're using the default settings, each time you start typing in Spotlight (to open an application or search for a file on your computer), your local search terms and location are sent to Apple and third parties (including Microsoft).
The Washington Post has published video demonstration of Yosemite's real time tracking.
Mac OS X has always respected user privacy by default, and Mac OS X Yosemite should too. Since it doesn't, you can use the code to the left to disable the parts of Mac OS X which are invasive to your privacy.
“Once Yosemite is installed, users searching for files – even on their own hard drives -- have their locations, unique user IDs and search terms automatically sent to the company, keystroke by keystroke.”
“It’s emerged that anyone who uses the Spotlight feature in either Mac OS X Yosemite or iOS 8 will have their location and search data passed to Apple servers.”
“Today’s web users have grudgingly accepted that search terms they type into Google are far from private. But over the weekend, users of Apple’s latest operating system discovered OS X Yosemite pushes the limits of data collection tolerance one step further”
“It's now common knowledge that companies like Google save your Internet searches … What's interesting about this case is that it involves searches on your own computer, not the Internet at large.”
“It's on by default – did you not read the small print?”
Disclaimer: Please be aware that this site is not affiliated with or approved by Apple, Inc. This site describes certain privacy-invading features of Mac OS X and how to fix them; our use of the trademarked term "Mac OS X" is plainly descriptive — it helps the public find this site and understand its message. This site is a Mac OS X fork of fixubuntu.com. Prior to Ubuntu 14.10, Ubuntu's Dash feature behaved identically to Spotlight in Mac OS X Yosemite. In Ubuntu 14.10, however, Canonical switched Ubuntu to an opt-in model.