Definition - What does Due Diligence mean?
Due diligence is standard of thoroughness which is supposed to be upheld in certain legal situations. For example, in property law, a party who wishes to acquire a new piece of real estate may be expected to carry out the due diligence of researching the building codes for the area, and ensuring that the property is not at risk of any violations.
Justipedia explains Due Diligence
Due diligence is basically just a certain level of care or effort that is supposed to be given to certain issues. There are multiple areas of law in which due diligence is relevant. Corporate and property law are two such areas. If a party has not given a certain issue the required level of effort or care, then they are said to not have done their due diligence. For example, in corporate law, a company that is taking over another company but fails to look into the assets and liabilities of the new company would be said to not have done its due diligence.