seo - Allow certain parameter in robots.txt

Question

I have this in my robots.txt and that needs to stay there:

Disallow: /*?

However I also need Google to index pages that have ?amp at the end of the url. Like this:

www.domain.com/product-name?amp=1

Is there a way to allow those in robots.txt, but also keep the Disallow mentioned earlier?

question from:https://stackoverflow.com/questions/65944510/allow-certain-parameter-in-robots-txt

Answer 1

To quote Google's documentation:

At a group-member level, in particular for allow and disallow directives, the most specific rule based on the length of the [path] entry trumps the less specific (shorter) rule. In case of conflicting rules, including those with wildcards, the least restrictive rule is used.

This means if allow ?amp but disallow folders above it, it should follow the more specific rule first and allow amp pages, but disallow anything higher in hierarchy.