Fiat Chrysler Automobiles on Sunday night defended a polarizing Super Bowl ad for its Ram brand that used a Martin Luther King Jr. speech delivered 50 years ago. The spot drew criticism on social mediaimmediately after it aired in the game's second quarter. Some observers knocked it for being tone deaf. But the company said it worked in collaboration with Martin Luther King Jr.'s estate on the spot.

"It is 50 years to the day that Dr. Martin Luther King Jr. gave such a tremendous speech about the value of service. Ram was honored to have the privilege of working with the Estate of Martin Luther King Jr. to celebrate those words during the largest TV viewing event annually," the company stated. "We worked closely with the representatives of the Martin Luther King Jr. estate to receive the necessary approvals and estate representatives were a very important part of the creative process every step of the way."

As the ad was being assailed on Twitter, another entity, The King Center, made it clear it had nothing to do with it. The center was founded by King's wife, Coretta Scott King, as a living memorial to the civil rights icon.

The ad, by a Chicago-based boutique ad agency called Highdive, used the audio of an MLK speech delivered on Feb. 4, 1968, against a montage of everyday people, along with shots of the Ram 1500 truck. The ad sought to portray a message of service. On its website, Ram plugs "Ram Nation," an organization of Ram owners that engages in service projects.

Read more about the campaign over at AdAge.com -- and see Ram's other Super Bowl spot, featuring a bunch of Vikings rocking out to Queen's We Will Rock You -- here.