Something like :
$data=~s/((.*)\/.*\/)\2/$1/g;

[download]
Could be a an approach.
But please give us more info about what you're manipulating for we can handle the (always present) special cases....

For a more precise answer, you should for example define :
How many times a string could be repeated (only once, more?),
what duplicates should be keept (first one, last one ?), if the duplicate can include a slash...

UPDATE : But as always all the useful info are in:
"Only Bad Coders Code Badly In Perl" (OBC2BIP)

In reply to Re: Removing duplicate substrings from a string - is a regex possible? by arhuman
in thread Removing duplicate substrings from a string - is a regex possible? by iakobski

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