Runner interference

[Der]

Bunted ball down first baseline. Pitcher fields ball and throws over runner down first baseline with first baseman standing on first. Ball and runner get to bag at the same time which causes first baseman to drop ball are they safe or out? Runner never left baseline. 

[grayhawk]

It might depend on what rule set they were playing under. When you say the runner never left the baseline, it sounds like he wasn't running legally in the runner's lane? If he wasn't in the runner's lane and the pitcher threw over him then:

In NFHS/NCAA, this is very likely runner's lane interference (RLI) because the runner, out of the lane, hindered the pitcher's THROW to first.

In OBR, this could be RLI if the runner being out of the lane hindered F3's ability to catch the throw.

[Velho]

Depends on what is meant by "never left baseline".

Considerations  that would make this legal and batter-runner safe include:

1) If the batter-runner stayed in the Runners Lane (which is the foul line on the left and three feet into foul territory on the right)

2) The batter-runner didn't intentionally interfere with the first baseman (such as waved arms, hit the glove)

3) The batter-runner didn't create contact (doesn't mean there was no contact but rather they tried to avoid contact /   didn't initiate contact) - some variation by ruleset.