Additional Paid In Capital (APIC) is the value of share capital above its stated par value and is an accounting item under Shareholders’ Equity on the balance sheet. APIC can be created whenever a company issues new shares and can be reduced when a company repurchases its shares. APIC is also commonly referred to as Contributed Surplus. Here is a decent website explaining it using Facebook as an example:

https://corporatefinanceinstitute.com/resourc...n-capital/