"This phenomenon is not very new: for some time, credit rating agencies have allowed some select corporations to achieve higher credit ratings than the sovereign in which they are located, which is called “piercing” (click here to read research on this topic by a PhD student at LSE). This is in fact a strange concept, but it occurs in both the developed and developing world, for corporations of all sorts (from commodity producers to banks and service providers). The countries in which piercing occurs include Italy, Brazil and India, among others."

https://sovereigndebtdotorg.wordpress.com/2013/11/26/the-los...

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Note added at 6 hrs (2017-01-14 20:37:19 GMT)
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Literalmente, empresas que conseguem notações mais altas do que as da dívida soberana dos países em que estão sedeadas, literalmente "furar" (em alta) as notações da dívida soberana do país em questão.

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Note added at 6 hrs (2017-01-14 20:39:28 GMT)
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https://www.researchgate.net/publication/265633940_Corporate...

"Under specific and very strict conditions, rating agencies now allow firms to obtain a higher rating than the sovereign of their incorporation (or location). The conditions for “piercing” the sovereign foreign-currency rating are stricter than for the sovereign local-currency rating [Moody’s 2006]. Bank ratings are almost never allowed to exceed the sovereign ceiling (in both foreign and domestic currency terms) because their fate tends to be closely tied to that of the government."