The company name must not be abusive, offensive to others or constitute an illegal act to use that name.
This rule is reasonably straight-forward and very few applications results in the company name being rejected by Companies House on the grounds that it falls short in one or more of the above criteria.
As with other aspects of choosing a company name, whilst there is no absolute and predefined rule book which stipulates what might fall in to the category of being abusive, offensive or illegal, Companies House will judge each case individually and retrospectively, will respond to complaints received from the public as always.