The family of the Rev. Martin Luther King Jr. is demanding a share of the proceeds from the sudden wave of T-shirts, posters and other merchandise depicting the slain civil rights leader alongside Barack Obama.

Isaac Newton Farris Jr., King's nephew and head of the nonprofit King Center in Atlanta, said the estate is entitled to hundreds of thousands of dollars in licensing fees — maybe even millions.

"Some of this is probably putting food on people's plates. We're not trying to stop anybody from legitimately supporting themselves," he said, "but we cannot allow our brand to be abused."

Obama accepted the Democratic nomination for president on the 45th anniversary of King's "I Have a Dream" speech, and America's first black president will be inaugurated on Jan. 20, the day after the federal holiday created to honor King, who was shot to death in 1968.

While Obama's election may be the fulfillment of King's dream, policing his image and actually collecting any fees could prove to be a legal nightmare.

Much of the great proliferation of unauthorized King-Obama paraphernalia is sold by street vendors, rather than through official outlets.

King's writings, likeness and voice are considered intellectual property, and almost any use — from graduate thesis papers to TV documentaries — is subject to approval by his estate, administered by his surviving children.

By contrast, Obama is an elected official so his words and image are in the public domain and may be used without permission.

Farris said he expects to announce deals in the coming weeks to license items featuring images of King and Obama, and may sell some in the King Center bookstore.

The center which sells recordings of King's speeches, postcards, calendars, mugs bearing images of King, and other licensed merchandise, nets about $800,000 annually.

But the family is protective of how King is depicted, and Farris said any items that are inconsistent with his uncle's message would not be approved.

Any proceeds from King-Obama merchandise would also go to the King Center, said Farris, a member of the estate management team that reviews intellectual property issues.

The family, which refuses to divulge details of its licensing deals, is also discussing how to go after violators.

In the past, the King estate has relied on concerned citizens to blow the whistle on vendors and manufacturers, who then get a cease-and-desist letter. If that fails, the estate sues.

"If you make a dollar, we should make a dime," Farris said. "That's not happening now."

King's estate sued CBS over its sale of a video documentary that used excerpts of his 1963 "I Have a Dream" speech.

An appeals court ruled in 1999 the speech was covered by copyright and was not public domain, but the estate ultimately settled out of court for an undisclosed sum.

"They are probably one of the most careful, concerned and on-top-of-it groups of image protectors I've ever met," said Philippa Loengard, assistant director of the Kernochan Center for Law, Media and the Arts at Columbia University.

Realizing the value of his ideas, King himself copyrighted several of his speeches during his lifetime.

After he died, that duty fell to his widow, Coretta, and, since her death in 2006, to their children, Martin Luther King III, Dexter King and the Rev. Bernice King.

Some scholars have complained about the family's aggressive pursuit of moneymaking opportunities.

"We realize the historic nature of events surrounding President-elect Obama and we are seeking an elegant solution to address the commercial use of Dr. King's image in connection with our newly elected president," Dexter King said in a statement.

With the siblings already battling in court over whether to publish their mother's diaries, it could be difficult for them to reach a consensus.

Jock Smith, an attorney for Bernice King and Martin Luther King III, warned that any action Dexter King takes without their approval would be "an illegal action not sanctioned by the corporation."

Street vendors Francis Sarr and Michael Silva said they are not sure whether anyone licensed the T-shirts for sale at their downtown Atlanta souvenir stand, including one featuring images of King and Obama and the words, "I HAVE A DREAM ... THAT CHANGE IS GONNA COME."

But they said they would be happy to contribute a portion of the proceeds to the King estate.

"By right, they definitely deserve something from it and should give their consent to sell it," Silva said. "I guess everyone is trying to cash in."