Delnorth Pty Ltd v Commissioner of Patents  FCA 165
This case illustrates the types of prior art information available for determining "innovative step" for innovation patents and "inventive step" for patents. In some case the difference can mean that a standard patent can be found valid while its counterpart innovation patent is found invalid.
Assessment of prior art information must be made in the shoes of the skilled addressee. That is, "the person skilled in the relevant art in the light of the common general knowledge".
The recent Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) has allowed greater leeway for combining 2 or more pieces of prior art information for testing inventive step - see this post on my website. However, the previous test is applicable in this case and will remain so for all patents with an effective date earlier than 15 April 2013. The previous test requires that the skilled person be reasonably expected to have ascertained, understood, regarded as relevant and combined the 2 or more pieces.
For innovative step, the assessment of prior art information includes determining whether or not prior art information made "publicly available in 2 or more related documents or through doing 2 or more related acts, if the relationship between the documents or acts is such that a person skilled in the relevant art would treat them as a single source of that information." This provision has not changed.
As you can see, it is conceivable that the test for combining documents can be stricter for standard patents than for innovation patents.
In Delnorth Pty Ltd v Dura-Post (Aust) Pty Ltd  FCA 1225, it was found that 2 counterpart innovation patents were invalid, having failed the "innovative step" test in light of 2 patents that fell within the definition of "prior art information".
In this case, however, the court held that the evidence did not justify a finding that a skilled person would reasonably expected to have ascertained, understood, regarded as relevant and combined the 2 patents. The evidence made no reference to the 2 patents. The court held that even "if they were known to him, they do not appear to have been perceived by him as relevant to the issues to which his affidavit was directed."
This matter appears to indicate that it is not enough to show that the skilled person would have carried out patent searches. Rather, it should show that the skilled person would carry out searches published in a particular period for the purpose of solving the problem to which the patent is directed.