Eligible Receiver

In American football and Canadian football, not all players on offense are entitled to receive a forward pass. Only an eligible pass receiver may legally catch a forward pass, or be more than five yards past the line of scrimmage on a forward passing play. If the pass is received by a non-eligible receiver, the penalty for "illegal touching" is assessed (the play is treated as an incomplete pass, unless the ball is downed behind the line of scrimmage - in either case a down is lost). If a non-eligible receiver is more than five yards downfield on an otherwise legal forward pass, the penalty assessed is "ineligible receiver downfield" (a loss of yardage, but not loss of down). Each league has slightly different rules regarding who is and is not considered an eligible receiver.
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