What is the difference between a primary issue stock, and IPO stock and a non-IPO stock?

When an organization sell new stocks to the investing public for the first time this is known as Initial Public Offering (IPO), this is mostly done through an investment bank or finance syndicate of securities dealers.

When an organization offers new stocks to the public, stocks that has not been sold before, this is known as primary issue stock.

In a situation whereby the organization has already raised an IPO and want to raise more funds by offering more shares, these shares will be categorized as Non IPO shares.
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When a company issues new stock (i.e., stock that has not been sold before to the investing public), the issue is considered a primary issue. if it happens to be the very first time ever that the issuer has sold any securities to the investing public, it is known as an initial public offering. if the issuer has carried out an ipo but wishes to raise more capital by issuing more shares, this subsequent offering would constituted non-ipo shares (since and ipo already occurred and can only happen once).