Argument on the side of the road about lost item

So I was riding down the 4 lane highway (grass median) and I saw a ladder that had fallen from a vehicle. I was going fast so I caught a U-turn, heading back the other way, made another U-turn to go get the ladder. As I approach and pull off the road a guy is backing up on the shoulder. I throw the ladder in my vehicle and he says that he was coming to get it. He asks if it was mine and I said no. He asks if I knew who it belonged to and I said no. So he tells me that it should be his because he was already backing up to get it. I explained that I had already turned around and doubled back to pick it up but he was adamant that it should belong to him. Who was in the right?