Littleton, 28, started 27 of 31 games across two seasons for the Raiders, and gives the Panthers depth at the position after acquiring Damien Wilson, who played last season with the Jacksonville Jaguars, earlier this month.
After spending his first four seasons with the Los Angeles Rams, Littleton signed a three-year, $35.25 million free-agent deal with $22 million guaranteed with the Raiders in 2020 and was expected to help in sideline-to-sideline pass coverage. Instead, he lost his starting job to rookie Divine Deablo late last season.
The Raiders labeled the transaction a post-June 1 designation, which will save Las Vegas $11.75 million against the cap after that date but will cost the Raiders $4 million in dead money this year and $10 million in 2023.
Littleton put up underwhelming numbers with the Raiders, posting just 0.5 sacks and a fumble recovery. He did not have an interception among his four passes defended. He also had six tackles for a loss among his combined 180 tackles.