m4siz patent infringement for website URL redirection

[PatentIssue]

Just had a letter from this company M4siz about a patent infringement, where our site redirects from;

domain.com/this

to

domain.com/that

Wouldn't that mean every website in the world has to use their patent. I searched in Google for them, but not a single page comes back about the issue, just business directories. Seems really odd for a patent that has been around since 27th October 2000?

Maybe its because there were URL redirects around before the filing date, but we would need to prove prior art or public common knowledge.

Has anyone else familiar with this company?

[PatentIssue]

maffski said:

This patent wouldn't apply if:
The redirect was being performed without a search - ie a fixed list of redirects
The search wasn't being performed as a part of the invalid document error handling - ie your URL rules were sending the visitor to a search page
The invalid document handling rules were redirecting the visitor to a search page rather than running the search directly

Thanks Maffski, we got the above items confirmed so we are fine