The Bar Code Prophecy by Suzanne Weyn

The third book in the Bar Code series, in which one girl struggles to escape the conformity of a dystopian world.

Just as in the original Bar Code Tattoo, the year is 2025 and the mysterious, ubiquitous, and seemingly omnipotent multi-national corporation, Global 1, is in power through their agent President Loudon Waters. But now this ominous situation is experienced through the eyes of sixteen-year-old Grace Morrow.
When Grace finds out that she's adopted, her biological father, who's the head of the Global 1 nano-bot injection project, urges her against getting the bar code tattoo when she turns seventeen. Stunned by the revelations, she goes home to find her adoptive family vanished, and she's determined to find them, turning to the anti-bar-code group Decode. As they uncover more information about tracking, Grace must hide deep underground and under cover, trying to discover information that will allow Decode to figure out what Global 1 is up to, and trying desperately to shut the organization down for good.

This book is part of the "Bar Code" series.
Here are some other books from this series: