Companies like Halliburton, Schlumberger, Weatherford, etc. That is where most of the expertise exists and these companies already work internationally.
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They must be doing all their fracking work in the USA however, because there isn’t much of it being done anywhere but the USA.
Most yes, all no.
for example, Halliburton is fracturing in Australia and Europe:
http://www.halliburton.com/public/projects/pubsdata/Hydraulic_Fracturing/fluids_disclosure.html
The point is, it is not knowledge limited to companies that only work in the US.
Four companies — Halliburton, Schlumberger Ltd. (SLB), Baker Hughes Inc. (BHI)’s BJ Services unit and FTS International Inc., formerly known as Frac Tech Services LLC — provided more than half the North American fracking services last year, Spears said. Halliburton was at the top of the group with almost one- fifth of capacity, followed by Schlumberger with 13 percent, BJ Services with 12 percent and FTS with 11 percent.
http://www.bloomberg.com/news/2012-01-19/frack-market-to-grow-19-in-2012-to-37-billion-correct-.html