Nehemiah 7:62-64

62 the descendants of Delaiah, Tobiah, and Nekoda. These people totaled 642.

63 These priests [couldn't prove they were Israelites]: the descendants of Hobaiah, Hakkoz, and Barzillai (who had married one of the daughters of Barzillai from Gilead and took that [family] name).

64 These people searched for their [family] names in the genealogical records, but their names couldn't be found there. For this reason they were considered contaminated and couldn't be priests.