I am wondering if a parent application of a divisional is ever granted by the USPTO if the divisional is granted. For example assume an inventor submits the parent A to the USPTO and is then instructed to file divisional(s) due to the fact that the parent A did not meet the unity of invention requirement - to which the applicant complies by filing a divisional B. Assume that B gets granted. Will A then be necessary denied granting? Thank you in advance.
First, the applicant is not instructed by the examiner to file a divisional. It is a choice the applicant can make if, in most of the world, the examiner finds no unity of invention between all the claims or, in the U.S. the examiner issues a restriction requirement.
At that point the applicant can push back or acquiesce. If they agree, in the present application (parent, application A) the applicant can cancel claims to the invention(s) they chose not to pursue in that application.
Either then or later, but during a prescribed time frame, the applicant can file a divisional (child B) claiming one of the other inventions.
Divisionals can be filed even without a restriction requirement from the examiner. The applicant can decide on their own to cancel claims and refile them in a divisional. Also, the specification might support claims to aspects of the invention that were not even in the original claim set. A divisional can have new claims directed to those aspects.
Applications A and B have separate, but related, lives. If two original claims were for distinct inventions either or both or neither might be patentable. One or the other or both might be granted - or none might be granted.
Once filed, the USPTO gives an application an application number. Fees are collected for filing, searching and examination. That number is attached to that application no matter what amendments might be made. New numbers are generated for reissues of an application. A divisional is another application with its own number and filing, search and examination fees.
Note - the criteria for unity of invention in most of the world and restriction requirement in US are not identical.