What are the rules regarding commercial use of the API? I assume it’s allowed but I cannot find any terms of use or conditions document about using the API online. There was something on the HMRC Developer Hub but I saw that Companies House is technically separate to HMRC so I don’t know if it applies.
Essentially, if I use this API to generate income as part of a business, what do I need to do? Do I need to register somewhere, or are there some rules that need to be followed.
API rate limits - You can make up to 600 requests within a 5 minute period.
API key security:
Do not embed API keys in your code
Do not store API keys in your source tree
Restrict API key use by IP address and domain
Regenerate your API keys
Delete API keys when no longer required
If you use the API to generate income as part of a business, you will need to register the business with either Companies House or HMRC depending on the nature of ownership of your business: Set up a business - GOV.UK
If you wish to run your business as a limited company or LLP, you will need to register with Companies House.