Thornton (back) does not have a designation for Sunday's battle against San Francisco, Paul Gutierrez of the Raiders' official site reports.
Thornton was activated from IR last Tuesday but was a healthy scratch Sunday versus the Jets. He picked up a back injury that resulted in a limited practice Thursday this week, but with a return to full participation Friday, the second-year wideout will be available to face the 49ers. However, it's unclear if he'll suit up Sunday given his healthy scratch last weekend.