To forfeit an agenda is to remove it from the game entirely, thus forgoing its points and any active abilities it may have. Card abilities can require either player to forfeit an agenda.

Page 22, Column 2, Paragraph(s) 1, Core Rule Book
Some card abilities require the Corporation or Runner to forfeit an agenda. When a player forfeit an agenda, he selects any agenda in his score area and permanently removes it from the game (it does not go to Archives or the heap). He no longer scores points for the forfeited agenda.
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