Can the fee reduction be claimed if an application, originally filed by a natural person, is subsequently transferred to a small entity or other than small entity respectively?

No, the fee shall be paid in accordance with the entity status of the new assignee. Additionally, difference in official fee chargeable from the new assignee and that charged from the natural person must be paid for all the official fee paid at the Indian Patent Office till the date of transfer of application or patent.

Same conditions would be applicable if an application/ patent is transferred from a small entity to an assignee which is other than small entity, or from a start up to a small entity or other than small entity.