We perform many tests internally, both for our SEO Spider software and as an agency for clients.This particular experiment was purely for fun to highlight the issue we discovered, without the intention of hurting anyone, or indeed for any profit.We have now ended the experiment and removed the content.

Background
We had previously been in touch with Google after noticing some strange behavior in the search engine results.While their SEO starter guide PDF was ranking for relevant terms like “SEO” and “google SEO guide,”something wasn’t quite right….For the searches we performed, the listing for the starter guide PDF would appear, but it would link to various other websites that had uploaded it rather than to Google’s own website.So Google wasn’t ranking its own page for some reason; other websites appeared instead, using Google’s content.

We decided to look into why Google’s page wasn’t being indexed and other pages were seemingly showing in its place.We noticed Google appeared to be using a 302 temporary redirect on their search engine optimization starter guide, which is hosted on a separate domain.Google was not using “noindex,” nothing was blocked via robots.txt, other content was indexed on the subdomain, and they didn’t appear to have any conflicting directives with canonicals or anything else on the page, or within the HTTP header.Obviously, the Screaming Frog website is not as authoritative as Google, but far less authoritative websites had already replaced them previously, due to the issues described above.

The experiment
We decided to run a short-term experiment and simply upload Google’s SEO starter guide to our domain.We then got it indexed via Google Search Console and forgot about it.A week later, we noticed we had hijacked Google’s own rankings (and any previous hijackers, due to our higher “authority”), as their algorithm seemingly believed we were now the canonical source of their own content.Our URL would return under a info: and cache: query for either of Google’s URLs.We were expecting this to change — for Google to become the canonical again and our page to drop out of the rankings.Up to five days later, we were still there, alongside Google in the search results for thousands of search queries.Then, our PDF disappeared from the search results, and we ended the experiment fairly swiftly.

Closing thoughts
First of all, we don’t recommend messing with other people’s content.This is not a viable strategy or tactic for gaining higher rankings, merely an unusual and interesting case study.It can be very difficult to draw conclusions,as we can’t always be sure what other factors or unknowns might be in play.

1.302 redirect not (fully) to blame
While we initially believed the 302 redirect might be the root cause, I know Google is adamant that there are no issues using 302 redirects. We believe there are some contributory reasons around how the files are hosted.

2.Use canonicals
It’s very wise to use canonicals to help with indexation.As soon as Google updated the PDF’s HTTP canonicals to a single URL, it was immediately indexed.Using a crawler, you can scan your site for missing canonical link elements or canonical links in your HTTP header.

3.Although rare, hijacking can occur
A page’s rankings can be hijacked by another domain that uses identical content under specific circumstances,such as problems with indexation or being a more authoritative source.

Source:Searchengineland

Peter Zmijewski is the founder and CEO at KeywordSpy.His expert knowledge on Internet Marketing practices and techniques has earned him the title “Internet Marketing Guru“ He is also an innovator, investor and entrepreneur widely recognized by the top players in the industry.