Not enough information.
In principle, fault lies with whoever could reasonably have acted to avoid the accident. If your car had been sitting there motionless for, I don't know, twelve seconds, and he came along and smacked into it, then it's almost entirely his fault for not paying attention or for going too fast or for whatever the reason was why he didn't stop in time.
If, on the other hand, you car was still rolling when he hit you, then it's probably almost entirely your fault for pulling out in front of oncoming traffic.
Or, it could be anywhere in between.
Any witnesses?
It's the backing out cars fault. Impeding the roadway. No one's going to believe you that they were looking the other way.
I would say probably the person backing out, as they should of looked for any oncoming cars before backing out. ---- The person backing out of the driveway who did not yield to oncoming traffic.
BOTH drivers are at fault for backing without caution. If the accident occurred in a driveway on private property, no ticket was probably issued. Turn it over to your insurance companies.
It depends on the type of insurance, the terms of the contract and the circumstances.
Generally, the one who was backing out of the driveway, because they are the one with duty to yield and also because they had the "last clear chance" to avoid the accident.
The person backing out of the driveway.
If you were fully in the lane, and he is backing from private property onto public property more than likely he will bare the majority of fault/liablilty.
It is usually the responsibility of the homeowner if a person pulls into a driveway and runs over a bicycle. The homeowner's insurance might also pay for this accident. It might be the driver's fault if the bicycle was not in the driveway at the time or the driver was drinking.
A turnabout
doesn't matter if an accident was on private property. get a police report immediately. this will be used to determine fault, if any.
nothing
Both states and municipalities establish traffic laws. In most instances person exiting a driveway whether private or public will be held accountable for an accident. The premise being, that driver is entering into the "traffic flow" and is required to use reasonable caution and take no action until the right-of-way is safely clear.
The car that is moving is normally the one at fault. No matter how someone is positioned you should not drive into them (going forward or in reverse). It therefore seems to me that the car backing out of the driveway is at fault.