After filing of the first patent application, applicants are given up to 12 months for filing patent applications in other countries that relate to the same invention. All of these applications that refer to the same so-called priority application form a patent family. The larger the patent family, the more extensive patent protection. Since each application involves costs, it is expected that an extensive patent family protects a significant and highly valuable invention.
However, there are some limitations to the validity of this measure. Patent family size also depends on technical fields. In some areas, it is sufficient to protect an invention in the major markets such as Germany, Great Britain or France, because it would not make sense for a competitor to market an invention only in the small, non-protected markets. On the other hand, marketing an invention in small countries only may be promising in some fields (e.g. pharmaceuticals) when production and market launch costs are rather low compared to market prices.
Again, on patent attorney profiles you will find an average of all applications an attorney has represented.