We are a raw material manufacturer, planning supplying to medical device industry. Are we required to comply with software validation section, that seems to be talking about medical device manufacturer, within ISO 13485:2016.
Applicability of ISO 13485 to your business is questionable, depending on the raw material that you supply to the customer. The clause 1 Scope of ISO 13485 says that the standard is applicable to organizations that need t demonstrate ability to provide medical devices and related services. It is limited to the organizations that are involved in one or more stages of the product life-cycle including design and development, production, storage, distribution, installation or servicing of medical devices. Supply of raw materials in not mentioned in the standard, so if you don't supply your customer with some parts of the medical device but only with raw materials, the standard is hardly applicable to your business.
If you don't have ISO 13485 certificate and are not planning to implement the standard, t he requirements for software validation are not applicable to you. If you are planning to implement the standard, exclusion of all requirements for software validation will be impossible, because the standard allows exclusions from clauses 6,7 and 8, but first requirement for software validation is in clause 4.1.6.
In your case, it might be better to implement ISO 9001 instead of ISO 13485, since it is more widely applicable and you can also include all requirements of your customer in your Quality Management System regarding medical devices, but you will avoid many requirements of ISO 13485 that would be redundant and inapplicable for your type of business.