Darin Hayes, is interviewing Timothy Brown from Football Archaeology. Besides the video we have the audio on our podcast too. Brown discusses a time in football history, from 1907 to 1911, when a tipped pass was considered a fumble. This means that if a pass was tipped by a player from either team, the ball was live and could be recovered by either team. This rule was implemented to increase player safety, as the forward pass was a new and dangerous play at the time. However, the rule was eventually changed because it led to too many scrambles for the ball, which could be dangerous for the players.
The video also discusses other interesting facts about the early days of the forward pass, such as how teams would sometimes try to create a circle of players around the receiver to protect him from being tackled.
Modern rules concerning a tipped pass go along these lines. A pass tipped by a defender can be caught by anyone on the field, including a previously ineligible offensive player. Only an eligible offensive player or any defender can legally bring a tipped pass by the offense.