On Monday, footballer Cristian Ronaldo effected a major change on the global value of a global brand when he moved two bottles of Coca-Cola away from him during a press conference for Euros 2020 in Budapest. Holding up a bottle of water and saying "agua" - Portuguese for water - Ronaldo appeared to be urging us to drink it instead.
Coca-Cola's share price dipped almost immediately by $4bn, promoting the international drinks company to respond with a statement saying “everyone is entitled to their drink preferences”.
This is not the first time a person in the public eye has influenced the world's financial markets.
In 2015, the former US secretary of state Hillary Clinton knocked $15bn (€13.5bn) from the value of US biotech stocks.
“Price-gouging like this in the speciality drug market is outrageous. Tomorrow I’ll lay out a plan to take it on,” Clinton wrote in a tweet, referring to a company that hiked the price of a medicine for a form of parasitic infection from $13.50 to $750 overnight.
Price gouging like this in the specialty drug market is outrageous. Tomorrow I'll lay out a plan to take it on. -H https://t.co/9Z0Aw7aI6h— Hillary Clinton (@HillaryClinton) September 21, 2015
The market value of Chipotle Mexican Grill - an American chain of restaurants - dropped by 2.7% in 2017 when Actor Jeremy Jordan said that he "almost died" after eating their food. “I know I’ve advocated for them in the past, but they’re terrible,” Jordan said in the now-expired Instagram story. “I, as you can see, am in the hospital and I have fluids in my arm because the food did not agree with me and I almost died.”
In a statement at the time, Chipotle denied any link between Jordan's illness and the chain.
Snapchat lost $1.5bn in market value in 2018 when Kylie Jenner tweeted about not being happy with the new design. "Sooo does anyone else not open Snapchat anymore? Or is it just me... ugh this is so sad," Jenner tweeted."
sooo does anyone else not open Snapchat anymore? Or is it just me... ugh this is so sad.— Kylie Jenner (@KylieJenner) February 21, 2018
There are times, of course, when a celebrity association will boost the fortunes of a company. In July of 2020, Oatly - a brand of oat milk - sold a minority $200m (€165m) stake to a group of high-profile investors, including Oprah Winfrey and Jay-Z. In May of this year, the Swedish company set its debut share price at $17 (€14) each and it shot to $22 (€18) in opening trading, valuing Oatly at more than $13bn (€10bn).