“Let’s get ready to rumble!” is the trademarked phrase of American professional ring announcer Michael Buffer. According to one trademark, Buffer first used the line in 1984.
 
Muhammad Ali (then called Cassius Clay) said in February 1964 before his world heavyweight championship boxing match with Sonny Liston, ““I’m ready to rumble. I’m ready to rumble.” Ali, however, did not trademark “ready to rumble.”
 
   
Wikipedia: Michael Buffer
Michael Buffer (born November 2, 1944) is an American professional ring announcer for boxing and professional wrestling matches. He is known for his trademarked catchphrase, “Let’s get ready to rumble!” He is known for pioneering a distinct announcing style in which he rolls certain letters and adds other inflections to a fighter’s name. His half-brother is UFC announcer Bruce Buffer.
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Trademark
Buffer began using the phrase “Let’s get ready to rumble!” in 1984. By 1992, he acquired a federal trademark for the phrase. Buffer uses his famous phrase in various licensing deals including the platinum selling album Jock Jams by Tommy Boy Records, the video games Ready 2 Rumble Boxing, Ready 2 Rumble Boxing: Round 2 for the PlayStation 2, Nintendo 64, Dreamcast and Game Boy Advance and Greatest Heavyweights of the Ring for the Sega Genesis and numerous other products. In addition, he has used variations of the phrase in advertisements, including the popular commercial for Mega Millions in which he says “Let’s get ready to Win Big!” and the Kraft Cheese commercial in which he says “Let’s get ready to Crumble!”.
 
As of 2009, Buffer had earned over $400 million from licensing on the trademark.
 
Google News Archive
25 February 1964, The Telegraph-Herald (Dubuwue, IA), “Fright or Fight? Clay Hit With $2,500 Fine,” pg. 11, col. 6:
MIAMI BEACH (AP)—Frantic Cassius Clay, labeled by a doctor as “a man who is scared to death,” put on a wild, loud scene at the weigh-in for Tuesday night’s heavyweight title bout with champion Sonny Liston and drew a $2,500 fine for his conduct.
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Clay made an early appearance at Convention Hall, stomping across the stage and thumping the boards with his cane as he yelled, “I’m the champion of the world. I’m ready to rumble.”
 
Google Books
Man of Destiny:
The story of Muhammad Ali, formerly Cassius Clay
By John Cottrell
London: Muller
1967
Pg. 130:
While court jester Bundini pranced around in the background like some witchdoctor as he went through his “Float like a butterfly, sting like a bee” charade, Clay thumped his stick on the floor and kept repeating, “I’m ready to rumble. I’m ready to rumble.”
 
Google Books
The Greatest:
My Own Story
By Muhammad Ali with Richard Durham
New York, NY: Random House
1975
Pg. 115:
“We’re ready to rumble! We’re ready to rumble!” we scream. “Float like a butterfly, sting like a bee!” we shout together. “This is it, you big ugly bear!” I shake my fist at Liston when he comes up to the scale in his white terry cloth robe. “It’s all over! You’ll be mine tomorrow night. I’m through playing with you. It’s all over now.”
   
New York (NY) Times
NOTEBOOK; Foreman Is Sparring With HBO
By PHIL BERGER
Published: July 11, 1990
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Michael Buffer, the ring announcer who is given to say, ‘‘Let’s get ready to rumble,’’ is a pretty fair mimic, good enough so that friends sometimes phone him using voices other than their own.
 
(Trademark)
Word Mark LET’S GET READY TO RUMBLE
Goods and Services (CANCELLED) IC 041. US 107. G & S: entertainment services; namely, the performance of an announcer at sporting and entertainment events. FIRST USE: 19840000. FIRST USE IN COMMERCE: 19840000
Mark Drawing Code (1) TYPED DRAWING
Serial Number 74442439
Filing Date September 30, 1993
Current Basis 1A
Original Filing Basis 1A
Published for Opposition April 18, 1995
Registration Number 1904692
Registration Date July 11, 1995
Owner (REGISTRANT) READY TO RUMBLE, INC. CORPORATION NEW JERSEY 24TH FLOOR 1801 CENTURY PARK EAST LOS ANGELES CALIFORNIA 90067
(LAST LISTED OWNER) BUFFER PARTNERSHIP GENERAL PARTNERSHIP 1801 CENTURY PARK EAST, 24TH FLOOR MCPHERSON & KALMANSOHN, LLP LOS ANGELES CALIFORNIA 90067
Assignment Recorded ASSIGNMENT RECORDED
Attorney of Record MARK E. KALMANSOHN
Type of Mark SERVICE MARK
Register PRINCIPAL
Affidavit Text SECT 15. SECT 8 (6-YR).
Live/Dead Indicator DEAD
Cancellation Date April 15, 2006
 
(Trademark)
Word Mark LET’S GET READY TO RUMBLE
Goods and Services IC 021. US 002 013 023 029 030 033 040 050. G & S: coffee cups, coffee mugs, [ plates, saucers, ] cups. FIRST USE: 19951100. FIRST USE IN COMMERCE: 19951100
IC 025. US 022 039. G & S: bathing suits, bathing trunks, bathrobes, beachwear, belts, Bermuda shorts, blazers, blousons, boots, bottoms, boxer shorts, bras, briefs, caps, cardigans, chemises, coats, cravats, dungarees, footwear, gloves, golf shirts, gym suits, jackets, jeans, jerseys, jogging suits, knit shirts, leather coats, leather jackets, neckties, neckwear, night gowns, night shirts, pajamas, pantaloons, pants, polo shirts, pullovers, quilted vests, sandals, shoes, shorts, slacks, sport shirts, sport coats, suit coats, suits, sweat pants, sweat shirts, sweat shorts, sweat suits, sweaters, swim trunks, swim wear, swimsuits, T-shirts, tank tops, tennis wear, thermal socks, thermal underwear, top coats, tops, tracksuits, trousers, turtleneck sweaters, turtlenecks, tuxedos, underclothes, undergarments, underpants, undershirts, underwear, V-neck sweaters, vests, warm-up suits, wind resistant jackets. FIRST USE: 19951100. FIRST USE IN COMMERCE: 19951100
Mark Drawing Code (1) TYPED DRAWING
Serial Number 75033678
Filing Date December 18, 1995
Current Basis 1A
Original Filing Basis 1B
Published for Opposition September 24, 1996
Registration Number 2166194
Registration Date June 16, 1998
Owner (REGISTRANT) Ready to Rumble, Inc. CORPORATION NEW JERSEY 29-J Hunters Glen Delran NEW JERSEY 08075
(LAST LISTED OWNER) READY TO RUMBLE, LLC LIMITED LIABILITY COMPANY CALIFORNIA 24TH FLR., 1801 CENTURY PARK EAST LOS ANGELES CALIFORNIA 90067
Assignment Recorded ASSIGNMENT RECORDED
Attorney of Record MARK E. KALMANSOHN
Prior Registrations 1904692;1905876
Type of Mark TRADEMARK
Register PRINCIPAL
Affidavit Text SECT 15. SECT 8 (6-YR). SECTION 8(10-YR) 20081113.
Renewal 1ST RENEWAL 20081113
Live/Dead Indicator LIVE