Will I be penalized for hidden content if I have text in a “read more” dropdown?

Matt's answer:

Today’s question comes from Jim. Jim asks, “Regarding hidden content, my site has a ‘Read More’ dropdown window to coexist with the simplistic design elements. The box contains optimized content, keyword anchor text linking deeper into the site, et cetera. Will I be penalized for this? Alternatives?” So here are the things to be aware of. Number one, let’s sketch out the bad side first. So if the bad side is if your dropdown is one pixel long and one pixel deep and the thing that gets revealed when you click on it is like eight pages filled with keyword-stuffed anchor text and things like that, that’s going to look pretty bad. If, however, you’re fitting within the normal idiom where you have a navigation menu and you click and it has revealed maybe a paragraph or two, maybe a link or two, that’s the sort of thing that a lot of different websites do. So this is the sort of thing where I would pay attention to what other websites do. If you use a common framework to do your dropdown that a lot of other websites use, then there’s less likelihood that we might accidentally classify it as hidden text. And then it would also really probably be a good idea not to put like eight pages of content in the stuff that people don’t normally see. Because what you want people to see is the same content that Googlebot is seeing. So you don’t want to land on a page that has nothing on it and have a whole bunch of text hidden behind a dropdown. But most normal sites doing most normal sort of mouse-activated dropdowns are doing a completely normal amount of stuff, and that’s not the sort of thing that I would really worry about. As long as you stick to common idioms the way that most websites do those sorts of dropdowns, as long as you keep it to a relatively reasonable length of text, I don’t foresee any problems.

by Matt Cutts - Google's Head of Search Quality Team

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