Grossman's agent, Drew Rosenhaus, made the official announcement today on Twitter:
Grossman is expected to join the Texans at minicamp next week. The deal is expected to be a one-year deal for the league veteran minimum of $620,000. Grossman joins starter Matt Schaub and backups Dan Orlovsky and Alex Brink as quarterbacks on the Texans' roster.
Grossman was drafted by the Bears in the first round of the 2003 draft. Grossman quarterbacked the Bears to a Super Bowl appearance in 2006, but eventually lost his starting job to Kyle Orton.