That's correct. The idea is that those who are making substantial and significant, or real contributions to or in support of a family business, who are working in it, or who have provided financing—it's not just labour contributions—would be unaffected and they wouldn't be subject to the tax on split income. It's really intended to apply in situations where you have, in a classic case, a high-income earner who earns monies in their law practice, which I'll use as an example because that's my background, and they divert it through one or more corporations to, say, their adult children or somebody else who's not involved in the business but who would be paying tax at a lower rate and would be able to effect tax savings because of that differential.
On April 24th, 2018. See this statement in context.