Ethics Question

Dave did nothing wrong legally or ethically, He simply "Got lucky" on a coin purchase

if I bought a bulk lot of coins and later found a rare coin in the lot, I certainly would NOT feel obliged to the seller in anyway.
I would however let them know that I found the coin and thank them for the purchase.

Come on you guys, This is what we do as collectors.
Most of us buy coins in the hope of getting a great deal or maybe something exceptional.
What would happen if anyone of you found a rare coin in your change or from the bank
I very much doubt that you would go running back and give the coin back to them

This "dave" Bloke is blameless and more luck to him I recon

General bourse floor "etiquette" goes like this.

Dealer to dealer can be law of the jungle, although it doesn't have to be that way. There are a lot of friendships and informal alliances among dealers.

Dealers are supposed to be ethical with collectors. It doesn't always happen, but there are a lot of decent, honest guys in the business.

What happens in a situation like the previous one? I had something similar happen once, although there wasn't nearly as much money at stake.

I asked a dealer I knew fairly well for a price on a 1921-D Mercury dime in an ANACS VF-25 holder. He looked at the coin and quoted me Fine bid ($125 or so) instead of the VF price of $250.

"You might want to check that price again," I said. This dealer had a great expression of relief when he saw the true value. I had done a fair volume of buying from him over several years and was always treated well and given competitive prices. It was payback time for one of the good guys in the business.

Not the same type of scenario here. What you did was the right thing to do because to have paid that dealer for a coin you knew was mistakenly under priced would have been unethical.

Dave bought a group of silver dollars from a dealer who should have checked each and every one when he purchased them so he would know exactly what he was getting for his money. He didn't and he didn't bother to go through them later as it turned out or the '93-s would not have been in the bunch of dollars Dave bought.

Every dealer I know with a B&M shop or not looks at each and every coin they buy for both the condition and date/mm so they don't over pay and to give the seller a fair price for their coins. One guy last year paid $900.00 for an XF-45 1909-S VDB a woman had in with fourteen other very common wheat back cents. He paid Three Cents each for the rest and they all went in his Wheat cent jar priced by the pound. She had no clue she had such a valuable coin. The dealer was very happy to have bought such a nice rare coin. He sold it for $1,100.00.

Ed
ANA LM-3175

I'm confused. I thought the OP was going to be an ethical question, but all I see is a perfectly unambiguous situation. Good on Dave.