Siddiqui are a South Asian Muslim Sheikh community, found mainly in India and Pakistan, and in expatriate communities in Saudi Arabia and Middle East Region. They claim to be the descendants of Abu Bakr, the first Sunni Caliph, who was a companion of and the father-in-law of Muhammad. Sociological study indicates they likely descend from a subgroup of the Hindu Kayastha record-keeper caste who Islamized at some point. The title "As-Siddiq" was given to the first Abu Bakr. His title "Siddiqui" is an attributive form of the Arabic As-Siddiq.