The scheme is available for small to medium-sized enterprises.
A small to medium-sized enterprise is defined as one that employs fewer than 250 people and has an annual turnover not exceeding €50 million, and/or an annual balance sheet total not exceeding €43 million. This includes sole traders.
You must not have received more than the permitted amount of de minimis aid in the last 3 years. There’s more guidance on this in the terms and conditions document.