The title Lord Falconer of Halkerton was created in the peerage of Scotland on 20 December 1646, for Sir Alexander Falconer, Lord of Session, with remainder to his heirs-male whatsoever. King Charles I granted Sir Alexander a yearly pension of £200 with the title, for his ability, integrity, and affection for administration of Justice.
David Hume's mother was the sister of David Falconer, 4th Lord Falconer of Halkerton. In 1778, the 7th lord inherited the Earldom of Kintore, and the two titles remained linked until 1966. The lordship then became vacant with the death of Arthur George Keith-Falconer, 12th Lord Falconer of Halkerton and 10th Earl of Kintore, although the earldom of Kintore continued in the female line.
Peter Serrel Falconer (died 2003), an architect, was the presumed heir to the feudal barony (1206) and Lordship (1646) of Halkerton, and had three sons, but did not pursue the claim. Other possible claimants included a West Indian civil servant and a Texan truck driver.
With the death of Arthur George Keith-Falconer, 12th Lord of Halkerton, the title "Lord Falconer of Halkerton" became dormant.
This means that an heir is believed to be alive, but it is uncertain who the heir is. It has to be the senior "heir-male", meaning that all the senior male lines need to be proven extinct.
In theory, the claimant would petition the Lord Lyon, King of Arms, for a grant of arms, claiming that he is the senior heir. Foreigners can receive grants of arms from the Lord Lyon, King of Arms, if they are the senior male-line descendant of a Scottish emigrant.