due diligence

noun Law, Business.

1. reasonable care and caution exercised by a person who is buying, selling, giving professional advice, etc., especially as required by law to protect against incurring liability: The court said there was due diligence on the part of the plaintiff.
2. the process of gathering or disclosing relevant and reliable information about a prospective sale, purchase, contract, etc.: You should perform due diligence on a company before investing.