Official Google answer: A site for my client's competitor shows up on a SERP for keywords that never show up in the site anywhere (not even hidden in the source code). How is this even possible, and isn't this spam?

Question:

A site for my client's competitor shows up on a SERP for keywords that never show up in the site anywhere (not even hidden in the source code). How is this even possible, and isn't this spam? What can my client do about it?

Google's Matt Cutts answers:

Summary of the answer:

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Question

Views

Uncrawled URLs in search results

1,127

If I use Google Analytics to track conversions on my ecommerce website, would that have a negative effect in Google SERP?

932

I have a client who was hacked. The SEO consultant said things were cleaned up, but they weren't correctly. All 30,000 viagra/cialis type and paid links have been removed, but no improvement in SERPs. We send reconsideration. What do we do now?

982

How would a photographer gain any significant PageRank for his or her site when the subject that really matters-images-has no anchor text?

1,005

Are there any APIs available from Google to pullout reports from Google Webmaster Tools?

909