Sam, who is seeking to become the first openly gay player in the NFL, signed with the Cowboys Wednesday after a physical.
"We just want to give him a chance to come in and help our football team," Cowboys coach Jason Garrett said Wednesday morning. "That's where our attention is. What people say outside the organization is up to them."
The rookie defensive end will be assigned to the practice squad, and isn't likely to be on the Cowboys' active season roster on Sunday's season opener against the San Francisco 49ers. He will be assigned No. 46, but those looking to buy a jersey should exercise patience: If he is promoted, his number will change.
Other teams could still sign Sam, but would have to put him on their 53-man active roster for a minimum of four weeks.
Practice squad players make $6,300 a week ($107,100 for the season), and if Sam is activated, he will make $24,706 per week.
Sam, who made history and headlines when he became the first openly gay player to be drafted to the NFL this spring, had a good showing in the preseason. He finished with 11 tackles and three sacks, but the defensively stacked Rams ultimately did not find room on their roster or their 10-man practice squad.
He cleared waivers and became a free agent Sunday.
The Cowboys, meanwhile, had a terrible defensive season last year, finishing last in yards allowed and had the sixth-worst pass rush in the NFL, with just 34 sacks in 2013.