(adjective) genuine, lawful,
bona fide = made or done in good faith - "The power to amend the articles must be exercised bona fide for the benefit of the company as a whole."
genuine: "There was a genuine dispute about ownership of the property."
authentic: "The seller was unable to produce an authentic deed proving that he had title to the property he was trying to sell."
sham: "It was alleged that the defendant had created a sham company in order to hide sales worth millions."
counterfeit: "More than 3,000 counterfeit DVDs have been seized by Trading Standards officers during an operation in Berkshire."
illegitimate: "The President has condemned elections held in the breakaway region on Saturday as illegitimate."