The prior art included a Chinese Utility Model known as Goodbaby, shown below:

It was common ground that Goodbaby did not show all the elements of the claim.  Missing were the fact that the seat was removably connected, so that it could be used as a car seat, and some elements of the claim concerning fabric support.

In the Patents County Court, England and Wales, Judge Birss (as he was) described the slightly unusual obviousness case based upon Goodbaby thus:

"Many obviousness arguments start from an item of prior art which differs from a claim and contend it would be obvious to modify the prior art in such a way as to remove that difference. The obviousness case over Goodbaby is of a different character. Phil & Ted's argues that if a skilled person put the disclosure into practice, without any inventive step, the resulting product would be a product within the claim. The argument is not focussed on modifying the disclosure."

One point concerned whether it would be obvious to start from Goodbaby at all, following somewhat ambiguous evidence on the point in cross-examination.  However, the Court of Appeal found that even if the evidence suggested that a person seeking to design a reversible car seat in general would not start from Goodbaby, it also established that Goodbaby was an obvious starting point for someone designing a baby buggy, and that reversibility per se was an obvious thing to do to Goodbaby.  The fact that a thing is non-obvious for one reason does not save it if it is obvious for another.  The judge was upheld.  

Written by David Musker, posted by Jeremy.