If an overseas company has no branch in the UK but wants to set up such a branch it may appoint a suitable senior employee to come to the UK, set up the branch, and manage it. Such a person may qualify for a Representative of an Overseas Business visa.
(NB: This is different from a Tier 2 Intra-Company Transfer visa: the UK branch has not yet been set up, and the Representative first of all has to set the UK branch up, and there is no formal sponsorship scheme for a Representative of an Overseas Business visa.)
The Representative must not be a majority shareholder of the company and must intend to work full-time for the UK branch of the company. If they are granted the visa they must not carry out any work for any organisation other than the UK branch.
There is an English language requirement, to at least CEFR A1 standard, and the applicant must show that there will be adequate salary from the overseas parent company to support them and any family members and that there will be adequate and appropriate accommodation.
Applicants must apply from outside the UK and close family members (spouse/partner, children under the age of 18) may apply with the main applicant as dependants.
Initial leave is usually granted for three years. If the UK branch is still existing and is significantly trading at the end of that three-year period the main applicant and any family members may be able to apply to extend their leave (but there is no requirement that the UK branch be making a profit). If this application is successful then the extension of leave will typically be granted for two years. After five years in total the main applicant and any family members may be able to apply for Indefinite Leave to Remain (settlement).