Although both Brazil and Vale remain intriguing options for investors, the existence of golden shares is something of a red flag that merits attention from international investors.

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The key feature is that the manager can flag what needs further attention or be passed upward in the organization.

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It used to be red-flag disorders like autism and attention-deficit hyperactivity disorder that attracted attention in early childhood.

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Someone or something has to truly flag them to catch their attention.

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This forcing of Americans to purchase a product is the constitutional red flag that now gets the most attention.

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The controversy over the Confederate flag in 2000 and the subsequent economic boycott by the NAACP drew national attention to racial tensions in South Carolina.

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They also exist to carry out research and, equally importantly, flag up emerging issues that the wider commercial community needs to be paying attention to.

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Mr. Pistorius's alleged connection to the shooting has drawn international attention, coming months after his historic appearance at the London Olympic Games, where he carried the flag for South Africa.

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