There is, generally, no direct legal requirement as such. Organisations choose whether or not to implement the requirements of ISO 27001 based upon the benefits that would be gained by doing so.
However, you should pay close attention to any contractual obligations you may have for protecting the information of clients and other stakeholders.
There is an increasing trend where customers require third party suppliers to implement or certify to ISO 27001, thus making it a legal requirement, by way of a contract.

Implementing Technological Controls in ISO 27001
URM’s blog offers key guidance on how to effectively implement technological controls in your organisation, the common challenges & how these can be overcome.
URM’s blog explains the importance of the 5 supplier management controls in ISO 27001 & provides practical guidance on how to implement each control.
URM’s blog explores why the access controls in ISO 27001 matter, and how to implement each control in full conformance with both the Standard and best practice.
URM’s blog explains the legal, regulatory & contractual controls in ISO 27001 & how they can be implemented in full conformance with the Standard.

