Editor’s Note: Paul Callan is a CNN legal analyst, a former homicide prosecutor and media law professor. He is of counsel to two law firms: Edelman & Edelman PC and Callan, Koster, Brady & Nagler LLP. The opinions expressed in this commentary are his.

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Donald Trump has trademarked the "Make America Great Again" slogan

Trump may be impolitic, but legally justified in trademarking the Reagan phrase, he says

CNN  — 

Don’t expect too many people to feel sorry for Donald Trump after he received a “Cease and Desist” letter from lawyers representing Aerosmith.

Lead Singer Steven Tyler is demanding that Trump stop using the band’s power ballad “Dream On” at campaign stops. And he isn’t the only one – 1970s icon Neil Young was similarly disturbed by Trump’s unauthorized use of his anthem “Rocking in the Free World,” while REM told Trump to stop using their song “It’s The End of the World As We Know It (And I Feel Fine).”

But it will be hard for Trump to claim the status of aggrieved victim when his own attorneys have so aggressively used their own threatening “Cease and Desist” letters in an effort to silence, for example, an anti-Trump “Club for Growth” TV ad. And they also warned a small Internet company, Café Press, which has produced T-shirts, coffee cups and other items bearing the slogan “Make America Great Again.”

Paul Callan

That last one you might think is a joke. After all, how can you own a phrase that was first used in presidential politics by Ronald Reagan in 1980? Well, Reagan, a former California governor, apparently lacked Trump’s expertise or interest in the “branding” of patriotic slogans. Or perhaps he just felt “America” was a word that already belonged to everyone in his beloved nation. Either way, it seems that Trump’s America is one where the old political niceties are gone, and if the law allows him to claim a hallowed phrase, well so be it.

And in fact the law may be on Trump’s side.

The reality is that Trump seems to have a keener understanding of the power of branding than he does of the political leanings of rock stars. In fact, he says he has a net worth in excess of $8.7 billion largely because of his success at marketing and protecting his brand. Though the reliability of this figure is widely disputed by his critics, Trump suggests that his proven business success demonstrates that he is the only current presidential candidate capable of creating jobs and rebuilding a vibrant American economy.

Whatever you think about his branding claims, the use of “Cease and Desist” letters is actually a common tactic utilized by trademark lawyers defending the trademarked names and slogans of their clients. But what is highly unusual in this situation is the insertion of trademark law into a presidential campaign regarding a phrase as common and as revered as “Make America Great Again.”

In the past, though trademark claims have been asserted by candidates for local offices, claims by presidential candidates are extremely rare. And although the presidential campaign of Republican Mitt Romney utilized extremely distinctive campaign logos and designs in his losing race against Barack Obama, none were ever trademarked.

Still, the Obama campaign, while bashing Romney’s capitalistic avarice while at Bain Capital, did not hesitate to trademark a distinctive campaign logo using the Obama “O” as a sort of rising sun, perhaps seeking to invoke a little of the Ronald Reagan (un-trademarked) “Morning in America” optimism. Obama campaign officials filed at least two lawsuits against vendors using the so-called “Rising Sun” logo of the Obama Campaign without permission.

Trump, though, is the first presidential candidate to register a trademark using the word “America.” And while most conventional politicians might fear a public backlash for trademarking the word, the strategy is in keeping with Trump’s unorthodox campaign. After all, he bragged in one debate about using bankruptcy laws to “do a great job” for his company because it was perfectly legal. In this case, his lawyers can certainly argue persuasively that he has the right to trademark “Make America Great Again” because the public now associates the phrase with Donald Trump.

What does the law actually say?

The law permits the trademarking of even common phrases when those phrases have acquired a “secondary meaning” in the marketplace as a result of advertising or continued usage. In Trump’s case, he has repeatedly worn a red baseball cap at campaign appearances displaying the words “Make America Great Again.” He also displays the hat and uses the phrase so often that many Americans have come to associate the phrase exclusively with Donald Trump. (When New England quarterback Tom Brady’s locker was photographed with a red baseball cap in it bearing the phrase in his Patriots locker, it was assumed to signify Trump support).

This is a classic example of how a heavily advertised phrase can become so closely associated with an individual that there is a substantial probability of public confusion or even fraud if others are permitted to market goods bearing the phrase. In addition, consumers might wrongfully assume that profits from the sale of such non-Trump “Make America Great Again” items are going to the Trump campaign, rather than into the pockets of possibly unscrupulous vendors.

The very same principle under trademark law has permitted Coca-Cola to have commercial rights to the phrase “It’s the real thing,” for Nike to inscribe “Just Do It” on sports products and for Verizon to have exclusive rights to the annoying “Can you hear me now” guy. The law doesn’t stop anyone from using a trademarked phrase in everyday conversations or in political debate. It simply bans the unauthorized sale of trademarked logos and slogans that have acquired a secondary meaning to avoid public confusion.

So Trump may well be impolitic, but legally justified in trademarking the Reagan phrase. We can also be grateful that Mr. Trump didn’t appropriate the slogan used by Republican James Blaine’s supporters in the presidential race of 1884, when Democrat Grover Cleveland was accused of fathering an out of wedlock child. During the bitter campaign Blaine supporters loudly chanted at Cleveland’s campaign stops:

“Ma, Ma Where’s My Pa”

After Gov. Cleveland narrowly defeated Blaine in an upset victory, his supporters had the final word:

“Gone to the White House, Ha, Ha, Ha”

Neither phrase has ever been trademarked. And that’s one thing we can be grateful for.

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