The team also reached a long-term deal with cornerback Stanford Routt and an agreement with defensive tackle John Henderson on a two-year, $8 million contract, league sources told ESPN's Adam Schefter.
The Raiders originally hoped to use a $3.5 million buyback option to keep Wimbley under contract for next season for just over $4 million.
But Wimbley's agent, Joe Linta, said the NFL determined that deal violated rules prohibiting base salaries rising more than 30 percent in a year. That led to the Raiders decision to use the franchise tag, which is projected to be worth about $10 million.
"Kamerion is a great young talent and he and the Raiders are excited about him continuing his career as a member of the Silver and Black," coach Hue Jackson said.
Wimbley led Oakland with nine sacks last season after coming over from Cleveland in a trade for a third-round pick. Keeping him was a key priority this offseason for owner Al Davis.
"We look forward to working with Mr. Davis on a long-term deal," Linta said.
The two sides can negotiate until the current collective bargaining agreement expires, which is currently scheduled for March 3. The non-exclusive tag means Wimbley can negotiate with other teams. But any team signing him would have to give the Raiders two first-round draft picks as compensation.
The Raiders' agreement with Routt is for 3-years and $31.5 million, with $20 million guaranteed, the source said.
The Raiders would not confirm the deal but made clear their desire to retain Routt.
"Stanford Routt is in his prime," senior executive John Herrera said. "He's a young, 27-year-old veteran, who already has six years of experience in the league. He's one of the fastest cornerbacks in the league and his best years are still ahead of him."
After slipping behind Chris Johnson on Oakland's depth chart in recent years, Routt had his best season in 2010. According to STATS LLC, opponents completed just 39.4 percent of passes against Routt -- one of the best marks in the league despite being a frequent target as teams stayed away from Nnamdi Asomugha's side. He improved markedly from 2009, when he allowed opponents to complete 65.9 percent of their passes.
While Asomugha was targeted on just 33 pass attempts this season, allowing 13 completions for 205 yards and no touchdowns, Routt was targeted 99 times. The completion percentage against him was the lowest in the league of any player targeted at least 60 times and was comparable to the numbers put up by the more heralded Asomugha (39.4 percent) and Darrelle Revis (33.9 percent).
With Asomugha a free agent who might not return to Oakland after his $16.8 million option was voided, keeping Routt was a high priority.
Henderson had 30 tackles in nine games last season for Oakland while being limited by a foot injury.
The Raiders have now retained three key defensive starters, having signed defensive tackle Richard Seymour to a $30 million, two-year deal last week.
Information from The Associated Press was used in this report.