Trump elected by narrow margin Lincoln assassinated by John Wilkes Booth There's an implied "to be" verb, generally "was". This is very common in headlines.

Trump elected by narrow margin Lincoln assassinated by John Wilkes Booth There's an implied "to be" verb, generally "was". This is very common in headlines. The comma introduces a parenthetical phrase describing Apple, implying Apple is going to do something: Apple, betrayed by its own law firm, countersues with gusto Apple, ["who was"] betrayed by its own law firm, believes the best revenge is living well