I would like to rewrite the sentence
"Patents are territorial. Because patent laws and examination processes vary between countries, patents must be filed in countries of interest in methods established by authorities of those countries. As a result, a patent application for an invention in one country is filed either in the same format or in different formats in other countries.'
as following 'It is because patents are territorial. Applications for an invention which have been filed in one country has to filed in other countries' authorities in terms of different patent laws and examination process among different countries. '
is it correct? Should I replace 'among different countries' by 'in different countries'?
Could you please give me some suggestions? please let me know, if you have any other advise about my sentence.
thanks in advance. best regards, Alex