After five years, you'll be fully 'vested' in the company pension plan. [=you will have earned the right to get a full pension when you retire]
Congress is 'vested' with the power to declare war. = The power to declare war is 'vested' in Congress.
She has a 'vested interest' in seeing the business sold, as she'll make a profit from the sale.
(..) # He's every bit # As good as what's-his-name # With a dame # Any dame # And all those bullet holes are in his vest # To prove you work a little harder # When you're second best... # - Courtesy of Mrs P. - Hm? You been up all night? (..)2011 Tinker Tailor Soldier Spy