Mary Umberger details that Sellers will bite at the right price, but there are ground rules when it comes to ‘pocket listings’: “When is a house for sale — but (sort of) not for sale?”
Mary goes into great detail on the following points on the 5 line items of a pocket listing

1. Homeowners try them out for various reasons, but mostly they’re motivated either for reasons of privacy or because they’re not terribly serious about selling,
2. A true pocket listing is when a homeowner and an agent have a casual agreement that if the agent comes across someone who might be a candidate to buy, the agent will bring that person to see the house.
3. Some sellers are more intent than those “maybe, someday” pocket listings, but they’re still not ready for all of the commitments of being listed
4. Then there are the cases where there’s a signed listing agreement and the homeowner wants active marketing but still doesn’t want to be in an MLS
5. Pocket listings can have their advantages, but generally they’re not the best tactic for most sellers — or for most agents