It's meaningless. Some brokers buy or sell for a client at a bid or ask price. Some people don't get to pick their price. That means is a thin after market a bid or ask price can be a dollar lower or higher than the closing price and the purchaser or seller may get locked into a higher or lower price. Unless there are millions of EXK shares trading in one single after market day then the after market trades cannot be looked at as anything significant.