The Dark ‘N’ Stormy cocktail consists of Gosling’s Black Seal Rum and ginger beer. Gosling Brothers Limited (a Bermuda corporation) trademarked the name in 1988—although the drink is said to have been invented after World War I—and won a 2009 trademark battle prohibiting other brands of rum in the cocktail. The name “Dark ‘N’ Stormy” comes from the line “It was a dark and stormy night…,” the famous and often-parodied opening of Edward Bulwer-Lytton’s 1830 novel Paul Clifford.
 
A Dark ‘N’ Stormy float adds rum raisin ice cream and has been served since at least the 2000s.
 
   
Wikipedia: Dark ‘N’ Stormy
A Dark and Stormy (or Dark ‘n’ Stormy) is a highball cocktail that is trademarked by Gosling’s Export Limited of Bermuda, makers of Goslings Black Seal Rum. The Dark ‘N Stormy is Gosling’s signature drink. This classic drink is popular worldwide, especially in many British Commonwealth countries, such as Bermuda and Australia. It consists of Gosling’s Black Seal Rum and ginger beer over ice. It is optionally accompanied by a slice of lime.
 
Bermuda
In Bermuda, Dark ‘N’ Stormy is a registered trademark of Gosling’s Brothers Limited. It is described as “Bermuda’s National Drink”, a description often applied to the Rum Swizzle as well.
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United States
The Dark ‘N Stormy gained popularity through the sailing community up and down the east coast of the US, having been brought home by various sailors who frequented Bermuda. Most bars in port towns from Portland, ME to Newport, RI to Annapolis, MD and beyond have the Dark N Stormy on their menu, made with various brands of Ginger Beer.
 
Gosling’s
DARK ‘N STORMY
Ingredients
1.5 oz Gosling’s Black Seal Rum
Gosling’s Stormy Ginger Beer
Method
In a tall glass filled with ice add 4 - 5 oz of Gosling’s Stormy Ginger Beer and top with Gosling’s Black Seal Rum. Garnish with a lime wedge (optional).
Gosling’s Black Seal Rum’s “Signature Drink”.
 
Google Books
Playboy Bartender’s Guide
By Thomas Mario
New York, NY: Barnes & Noble
2003, ©1979
Pg. 199:
DARK & STORMY
3 oz. dark rum (Gosling’s)
8 oz. ginger beer
Pour rum and ginger beer over ice into 13-oz. hurricane glass.
   
New York (NY) Times
Shaken & Stirred
The Right Stuff (by Law)
By JONATHAN MILES
Published: July 2, 2009
“What’s in a name?” Shakespeare famously asked. In the case of the Dark ‘n’ Stormy, a Bermudan cocktail that’s been making a quiet resurgence in New York City bars and restaurants in the last couple of years, it’s two ounces of Gosling’s Black Seal rum and a fizzy hit of ginger beer.
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Where Mr. Gosling — and his legal team — draw the line is the presence of other rums in a so-called Dark ‘n’ Stormy, which was invented in Bermuda just after World War I. “People will try one with some other rum, and then say, what’s the big deal with this drink?” he said. “That’s a real concern.”
 
Serious Eats
The Dark ‘n’ Stormy Showdown of 2009
Paul Clarke
Aug 5, 2009
3:45 PM
“Should cocktail recipes be legally limited to a particular product or brand?”
In case you thought bibulous brand-battles were limited to Coke vs. Pepsi, take a look at the storm that’s brewing regarding the venerable rum drink, the Dark ‘n’ Stormy.
 
As Jonathan Miles noted in his New York Times Shaken & Stirred column last month, the Dark ‘n’ Stormy is made with Gosling’s Black Seal rum and ginger beer—that’s it. But this level of specificity isn’t a case of brand placement. Gosling’s filed two trademark certificates that dictate the precise ingredients in a Dark ‘n’ Stormy, and needless to say, one of those ingredients is the company’s signature brand of Bermuda rum.
   
Google Books
101 Tropical Drinks
By Kim Haasarud
New York, NY: Houghton Mifflin Harcourt Publishing Company
2013
Pg. 27:
DARK & STORMY
One of the very few cocktails where a brand has actually succeeded in trademarking a cocktail (sort of). Technically, you can’t call it a “Dark & Stormy“ if you don’t use Gosling’s Black Seal rum, but, in all honesty, there are really only a few other rums on the market that could even come close to duplicating the same flavor.
 
(Trademark)
Word Mark DARK ‘N STORMY
Goods and Services IC 033. US 049. G & S: PRE-MIXED ALCOHOLIC COCKTAIL, NAMELY RUM AND GINGER BEER
Mark Drawing Code (1) TYPED DRAWING
Serial Number 73705138
Filing Date January 11, 1988
Current Basis 44E
Original Filing Basis 44E
Published for Opposition June 25, 1991
Registration Number 1657574
Registration Date September 17, 1991
Owner (REGISTRANT) GOSLING BROTHERS LIMITED CORPORATION BERMUDA P.O. BOX 827 HAMILTON 5 BERMUDA
(LAST LISTED OWNER) GOSLING’S EXPORT (BERMUDA) LIMITED CORPORATION BERMUDA 12 DUNDONALD STREET HAMILTON HM12 BERMUDA
Assignment Recorded ASSIGNMENT RECORDED
Attorney of Record ANDREW N. FREDBECK
Type of Mark TRADEMARK
Register PRINCIPAL
Affidavit Text SECT 15. SECT 8 (6-YR). SECTION 8(10-YR) 20120127.
Renewal 2ND RENEWAL 20120127
Live/Dead Indicator LIVE
 
(Trademark)
Word Mark DARK ‘N STORMY
Goods and Services IC 025. US 022 039. G & S: clothing, namely, shirts, hats and jackets. FIRST USE: 19900000. FIRST USE IN COMMERCE: 19900000
Mark Drawing Code (1) TYPED DRAWING
Serial Number 74694951
Filing Date June 29, 1995
Current Basis 1A
Original Filing Basis 1A
Published for Opposition August 6, 1996
Registration Number 2011630
Registration Date October 29, 1996
Owner (REGISTRANT) Gosling Brothers Limited CORPORATION BERMUDA 17 Dundonald Street Hamilton BERMUDA
(LAST LISTED OWNER) GOSLING’S EXPORT (BERMUDA) LIMITED CORPORATION BERMUDA 9 DUNDONALD STREET HAMILTON HM10 BERMUDA
Assignment Recorded ASSIGNMENT RECORDED
Prior Registrations 1657574
Type of Mark TRADEMARK
Register PRINCIPAL
Affidavit Text SECT 15. SECT 8 (6-YR). SECTION 8(10-YR) 20061222.
Renewal 1ST RENEWAL 20061222
Live/Dead Indicator LIVE