This is a fascinating and important amendment that would have a far-reaching effect on the whole of the European patent system. As I understand it, not many countries, if any, allow patents to be valid even if it later transpires that the invention that was patented was in the public knowledge at the time it was patented.

The amendment would therefore make a major change to the structure of the European patent system, and would, as the hon. Gentleman suggests, encourage people to keep an eye on the patent system as patents are being granted. However, it is such a major change that I wonder whether it might not be preferable to introduce it—if it is introduced at all—after consultation with industry. Comments on the Bill that I have received from those interested in patents range from those of the Patent Reform Group, which says that the whole patent system is ranged against the

small inventor and small company and needs root and branch reform, to those of several other operators in the field, which say that, by and large, this is a good, small, sensible Bill that ought to be passed without many changes.

The change in the amendment would be so large that it needs consultation before it becomes the law of the land. At present, I am not opposed to the broad thrust of the hon. Gentleman's ideas, because a degree of protection, which is not currently available, is needed by small businesses. The costs of taking out a patent and of enforcing it are so daunting as to put off many small inventors. As I said on Second Reading, something needs to be done to protect small and medium-sized enterprises.

Finally, it is not always the small and medium-sized enterprises that are protecting the patent. Sometimes, the big guys—the big companies—exercise control in a way that the hon. Gentleman suggested the small companies should. Enforcement in this area is a reciprocal issue—a two-way street. We need to consider changes such as the one that he proposes carefully, but after consultation with industry.