Could be a liability hunt as the guy you sold it to maybe didn’t have a pot to piss in so people getting a sniff of possible money. In some states, it is CLEAR that the buyer has responsibility to re-title the vehicle and within so many days. The seller and buyer sign off on the transfer of title at the time of sale so the DMV can issue a new one under the buyer’s name. A BOS noting the selling of the vehicle, date, etc. makes it clear ownership has changed. If the title you handed over to the buyer is around this should also note the transfer. Not sure if every state has similar laws. Adding to my earlier post, another thing I’ve done is make a copy of the title with both signed off at time of sale so I have this as a record as well.