Observations: If you are aware that a third party has a pending patent applicatuion in the UK and you have grounds for preventing the application from granting, it is possible to file "observations" which the Patent Examiner will take into consideration.
Office action: An “Office action” is a term used by the US Patent Office and also in some other countries to refer to what would be called an examination report in the UK and Europe.
OHIM: OHIM stands for the Office for Harmonization in the Internal Market. It's offices are based in Alicante, Spain and it is the official trade mark and designs office of the European Union. Community Trademarks (CTMs) and Community Registered Designs (CRDs) are registered at OHIM and provide protection across all 27 member states of the European Union.
Opposition: There is a 9mth period following the grant date of a European Patent in which 3rd parties may officially object to the granted patent and if successful, can have the European patent cancelled or nullified. There are only limited grounds for Opposition and these are set down in law.
Ownership: The default arrangement in the UK is that the inventor is the first owner of an invention. However, when the inventor is an employee and the invention was made during the course of employment, then the invention may belong to the employee. However, this very much depends on the invention and the circumstances surrounding its creation.