Impinj shares pare gains as Amazon.com says no RFID used at automated store

Signage is seen inside Amazon’s first cash register-free grocery store, in Seattle, Washington, U.S., January 18, 2018. Photo taken January 18, 2018. REUTERS/Jeffrey Dastin

SAN FRANCISCO (Reuters) - Shares of radio-frequency identification (RFID) chipmaker Impinj Inc pared gains on Monday after Amazon.com Inc said its new checkout-free grocery store, which opened to the public on Monday, does not use the technology.

Investors have speculated that Impinj could sell components to Amazon. Its shares surged as much as 18 percent earlier in the session. They were up 8.5 percent at $25.19 in early afternoon trading.

(Reporting by Jeffrey Dastin; Editing by Bill Rigby)