Klout is an online service that measures your influence by analyzing your interactions on social networks. If you have a public Twitter account, your Klout profile is automatically created, regardless of whether you signed up for the service or not.
Other Internet services, like search engines, can access your Twitter feed as well, so Klout isn't unique when it comes to gathering your Twitter data. Klout, however, allows you to opt-out of their service. Here's how:
Step 1: To begin the opt-out process, go to http://klout.com/corp/optout and click on the Twitter or Facebook link at the bottom of the page.
Step 2: Authorize the opt-out app to use your Twitter or Facebook accounts.
Step 3: Fill out the opt-out form and click on the "Submit" button.
That's it. For those of you who have a Klout account but want to delete it, make sure you're logged in to your Klout account before visiting the opt-out page. Your profile will be removed from Klout's Web site within 48 hours and the API within a week. Remnants of your data may linger for up to six months, however.