BioPay LLC, a Herndon company that sells biometric technology that allows consumers to pay for goods by scanning their fingerprints, agreed to be acquired by San Francisco rival Pay by Touch for $82 million in cash and stock.

Both companies have technology that works by scanning people's fingerprints and matching the results with their bank accounts.

BioPay, founded in 1999, has installed its system at about 1,600 retail stores around the country, including several convenience stores in the Washington area. Its system is also used to identify consumers at check-cashing locations.

Pay by Touch's technology is being used at about 300 retail stores, and the company has contracts with several grocery chains.

Pay by Touch will take over all of BioPay's retail customers, as well as its database of consumers and portfolio of patents. The companies say their systems offer speedier checkout lines for consumers and lower transaction fees for retailers, but some privacy-rights advocates have voiced concerns that the firms have amassed huge databanks of personal information.

BioPay's chief executive, Tim Robinson, will stay with the company. Pay by Touch officials said it has not yet been determined whether there will be layoffs among BioPay's 74 employees.

The deal is expected to close in the next few weeks.