Some northern Nevada counties use blockchain, the best-known online registry to help secure virtual currencies such as bitcoins, to store digital versions of government documents such as birth and marriage certificates.
The Reno Gazette-Journal reports that in Washoe County, between April and December 2018, around 950 couples received secure digital marriage certificates for home computers and smartphones.
The newspaper found that Elko County is testing similar technology for certified digital birth certificates.
Phil Dhingra of Titan Seal, based in San Francisco, says the blockchain has computing power that makes hacking difficult.
Today, anyone with a paper marriage certificate in Reno also gets a free certified digital copy, sometimes in less than 24 hours.
This is because state law says that the county can not charge separately for a certified digital copy.