Using a single FHIR server for multiple companies/practices & Cures Act compliance

We’re a small EHR vendor that is working on complying with the Cures Act.

Is it feasible to use a single FHIR server instance for multiple companies/practices at once?

Spark seems like the best solution, since it’s open source (customizable) and written for .Net in C#.

Because it’s open source, we could technically modify it to handle multiple companies. As an example, we could add the company ID to relevant tables, so when a user is pulling data for a patient, it only pulls data for the patients for the company ID that they authenticated with.

I can’t speak specifically to regulatory requirements, but having multiple practices served by a single server is quite common.