The company was forced to 'declare bankruptcy'. [=to formally say in a legal document that it was bankrupt]
He 'declared' himself the winner. = He 'declared' that he was the winner. = He 'declared victory'.
His 'declared' [=publicly stated] aim/goal/intention is to improve the city's downtown area.
(..) industrial plastics. Aah. Very interesting. Well, here is looking at you, kid. You have anything to declare? Nothing. You may proceed. I come here very often. I come here for the winter sports, for the skiing. So do I. (..)1975 The Return of the Pink Panther