A round robin resolution can be passed by a majority of the directors (provided all directors get notice of the proposed resolution) unless the MOI of the company provides otherwise (section 74(1) of the Companies Act 2008). But many registered companies have not updated their MOIs and still use the form of the old Table B under the 1973 Companies Act which requires a round robin resolution to be signed by “all the directors”.
When dealing with or for a company that authorises an act by round robin resolution, you need to find out exactly what is in the MOI in case it overrides the latest rule that only a majority of directors needs to pass a resolution even when no meeting is held. Companies still using Table B should update their MOIs and get the advantage of the modernising provisions of the 2008 Companies Act.