I have a marketing campaign landing page and it uses a tracking URL to track clicks. The tracking links look something like this: http://this-is-the-origin-url.com/clkn/http/destination-url.com/ The problem is that Google is indexing these links as pages in the SERPs. Of course when they get indexed and then clicked, they show a 400 error because the /clkn/ link doesn't represent an actual page with content on it. The tracking link is set up to instantly 301 redirect to http://destination-url.com. Right now my dev team has blocked these links from crawlers by adding   Disallow: /clkn/   in the robots.txt file, however, this blocks the flow of link equity to the destination page. How can I stop these links from being indexed without blocking the flow of link equity to the destination URL?