Do any of the database vendors or patenting bodies provide classification metadata? By this I mean, is there a record of patent classification (US, ECLA, IPC, Other) on a given date, particularly a date in the past?
My situation is this...
A full, manual search of a subclass was performed on a given date. Today, this subclass does not exist but I would like to identify the exact art which was manually reviewed during the prior search.
Hypothetical: The Class/Subclass in question is US Class 705, Subclass 1 and it was searched in January of 2010. Since then, it has been abolished and the art reclassified into dozens of existing and new subclasses. Using the USPTO systems, I can search by original classification and current classification, but there appears no way to search for an intermediate step between those two extremes.
I've sent my query to Steve and Terry from the USPTO who presented at the 2010 Annual Meeting and if they have a solution, I will post it.
Edit (2/8/2011): Terry at the USPTO says they have the means to recreate any subclass on any given date should they need to.
P.S. This problem could be avoided if we saved the patent or record numbers for what was reviewed. Unfortunately, for space saving purposes, we often only record the strategy and total number of patents or records returned.