Flybe - 3 (Including the FlyBe/BACon merger)

[JobsaGoodun]

swedish

Slots can be transferred, however in theory you cannot trade slots. It does happen, often with plenty of money changing hands too, particularly if its somewhere like LHR for example.
The slots are owned by the airline operator and, to my knowledge, do not change based on flight number. With Flybe acquiring BACon, all of BACon's slots at the various airports operated to/from will become Flybe's, otherwise you acquire an airline with no viable routes!