There are two scenarios where I am unsure what the practical limit on the number of "Communications"/objections from an EPO examiner would be. However, I do realize that the annuity fee requirement of pending EPO applications may be a way to make the applicant pay for/compensate prolonged examination.
1) Performing subsequent rounds of narrowing(/broadening?) amendments on the originally filed claims, that (a) are supported by the specification (e.g. long list of "prose form" claim alternatives included, or long list of claims originally filed then cancelled upon fee request), and (b) still satisfy unity of invention (e.g. assume no "a posteriori" lack of unity of invention issues arise).
In the US it is not uncommon for some applications to go through multiple rounds of back and forth with the examiner (e.g. 3+ RCEs), where the argument is over applicability of the cited prior art, and/or a sequence of minor claim adjustments are made. What is the analogous scenario for EPO prosecution? E.g. does the examiner and applicant go back and forth on multiple rounds of communication (e.g. up to 10 times in some cases), does lack of substantive arguments against the examiner constitute an essential abandonment of the application, and/or do the amendments generally require new searches to be paid for/performed?
2) Replacing all claims with a new invention (supported in a "compound" application), and paying the supplementary search fee.
The purpose of (2) is to avoid repaying the examination fee and a second set of annuities in a divisional application, in the case that the applicant has decided to "abandon" the original claim set. However, this would essentially double the number of Communications from the examiner. Is this allowed?