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Luxury Swiss watchmaker Rolex has demanded an apology after the Italian government linked the brand to violent clashes in Milan on Friday.

Interior Minister Angelino Alfano called the rioters demonstrating against Milan's Expo trade fair "spoilt brats with Rolexes".

In response, the company took out advertisements in Italian newspapers saying their image had been unfairly sullied, arguing it was difficult to tell whether a timepiece seen on a protester's wrist really was a Rolex.

But was this the right reaction? Dr Ben Voyer, a marketing professor at ESCP Europe Business School and visiting fellow at the London School of Economics, said firms risk overreacting when responding to events beyond their control.

"Replying is not necessarily a good thing," he said. "It is very difficult to dispel negative stereotypes - a quiet press release might have been better for Rolex."

Brands face a constant battle to control their image. Here are some other times when companies became unwittingly caught in major events.

BlackBerry

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BlackBerry has seen both the good and bad sides of popular endorsement - the firm's PR department must have rejoiced when it emerged US President Barack Obama was a fan.

Once the must-have smartphone, the company won a reputation for innovation.

But how that innovation is used is difficult to predict, as BlackBerry found when some of those involved in the 2011 London riots used their devices to organise lootings.

Teenagers were attracted to the company's phone-to-phone messaging service, long before the likes of WhatsApp made free messaging widespread.

BlackBerry, in response, offered to assist police, but then was attacked by hackers angry that the company was prepared to hand over user data to the authorities.

Skittles

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Skittles became an unlikely symbol of the death of 17-year-old Trayvon Martin, who was shot dead by neighbourhood watchman George Zimmerman in Florida in 2012.

Martin was carrying a bag of the sweets and a bottle of iced tea at the time of the incident.

Bags of Skittles were a common presence at the protests that followed his death. To demonstrators, they represented his youth and innocence, with the "Taste the Rainbow" slogan taking on new significance given what they believe was a racially-aggravated murder.

Some were uncomfortable with the commercial aspects to the protests, calling on Skittles to donate any increased profits.

Wrigley, Skittles' makers, would not be drawn in, offering condolences to Martin's family and saying it would be inappropriate to comment further.

Ikea

Image copyright AFP/Ikea

As the Trayvon Martin case shows, anything can become an icon.

A stuffed toy wolf called Lufsig inspired by the fairy tale Little Red Riding Hood sold out in Hong Kong in 2013 as it surged in popularity among anti-government protesters.

A protester had flung one of the toys at Hong Kong's leader, CY Leung. Its name also sounded similar to a Chinese profanity, and Mr Leung had been nicknamed "the wolf".

Ikea would not comment on the political connotations the toy wolf had developed, but did say that none of its products in Hong Kong, including its soft toy range, had Chinese names.

Mr Leung later posted a picture of him posing with Lufsig, praising Hong Kongers' "creativity".

Hennessy

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A number of famous brands have been linked to authoritarian leaders. Former Iraqi leader Saddam Hussein reportedly enjoyed Bounty chocolate bars while trying to evade capture from the US, and it emerged that Syria's Bashar al-Assad was a keen user of Apple products when a batch of his emails leaked.

Neither though could be said to be one of the companies' main buyers, as former North Korean leader Kim Jong-il was with Hennessy cognac.

Kim, who ruled over a country mired in poverty, reportedly spent hundreds of thousands of dollars a year on the product.

A Hennessy spokesperson said after his death the endorsement had not hurt sales, and that it was not unusual he would want their product.

"It's a very large status symbol, and we're one of the premier luxury cognacs in the world, and it's not surprising that he would gravitate towards that," Jennifer Yu told Foreign Policy.

Dr Voyer said consumers are unlikely to blame companies for unwanted associations: "There's nothing you can do about it. Of course some people are not the intended target for a brand."