actually it happens very often but most cases are easy solution.
Frank spoke of a possible solution/workaround of clearing all doubts. If doable, perfect \o/
but, this topic started as "Opposite of stealing secondary resources", meaning several players delivering to a factory (example) but only one (the one that delivered there first) taking the goods.
ofc, there are several constraints that can be added to the situation but in general it's respecting server rules. As Hawky said, "That's the other players problem. It's his choice to transport cargo to your factory.", since they understand that at any point can claim goods from there! (unless 1st company that delivered there, explicitly allows it).
So, what
Joe
wants to know is: Globally there's no problem with the situation you described.
But each game is different from previous one, and game situations vary too. In case of fire(doubts),
call an admin to clarify it