Can I collect royalties from a patent that a company in another country is producing that my grandfather invented? My grandfather J.F. Mcdowell invented & patented the fishing tool used on oil rigs to retrieve tools that get dropped in a borehole. I've researched the timeline and discovered that many foreign businesses are producing the exact tool my grandfather invented. When researching the companies and the patent filed within that country, J.F Mcdowell is listed as the inventor. Is my family entitled to royalties??
I see in the comments you list EP0460797A1. This application was granted as EP0460797B1 on 06/21/1995 and expired on 04/23/2011. So this patent is no longer in force and the invention described by it is freely available for anyone to use anywhere in the world. Even if it were in force, I doubt you would have any claim to royalties as the assignee is BetzDearborn Europe Inc. It is very common for inventions done while an employee to be owned (assigned) to the company and not the inventor.
Although you cite EP0460797A1, I rather doubt that this is invented by your grandfather. I found three US patents invented by John Frank McDowell including US1374510A, "Fishing Tool". These three patents were all in the US and all from the 1920s. Since patents of those eras expired 17 years from the grant date, they have all expired long ago. It is relatively common to have inventors with the same name so you have to be careful when searching.
In any case whichever John Frank McDowell we are citing, the patents are no longer in force and there is no potential for royalties.
You can look up the patent application status at Espacenet as well as other sites. It was filed in 1991 and therefore its 20 year term was up in 2011. The legal status page is here.
If it was not expired any royalties would be due to the owner of the patent not necessarily an inventor or heir.