Melifonwu, 26, is a former second-round pick of the Raiders back in 2017. He was in the second year of his four-year, $4.5 million contract when the Raiders waived him in November of last year.
The Patriots quickly signed Melifonwu to a contract and he finished out the year in New England. New England waived him coming out of the preseason and later signed him to their practice squad last year.
Melifonwu was later placed on injured reserve.
In 2018, Melifonwu appeared in seven games for the Raiders and Patriots and recorded seven tackles and no interceptions.