If your U.S. corporation is at least 25% owned by a foreign entity or person, then you're required to file Form 5472 and Form 1120, which will report any business you had that was involved in US Trade or Business as well as let you know how much income tax liability you have.
However, generally speaking, as long as you don't have a physical presence in the US and are a purely online business, you will only need to make an informational filing in the US and not pay US income taxes (you'd then pay income taxes only in your home country).
Physical presence = you are in the US, your employees are, you have a physical office, etc! If none of these apply then you don't have a physical presence.