The inverted hammer occurs when price has been falling suggests the possibility of a reversal. Its long upper shadow shows that buyers tried to bid the price higher.

However, sellers saw what the buyers were doing, said "Oh heck no" and attempted to push the price back down.

Fortunately, the buyers had eaten enough of their Wheaties for breakfast and still managed to close the session near the open.

Since the sellers weren't able to close the price any lower, this is a good indication that everybody who wants to sell has already sold. And if there are no more sellers, who is left? Buyers.