Companies such as ASITE, Autodesk, Earthcam, NRI, and Verizon Wireless got on board.

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Not surprising considering they have one-sixth of the world's population as a captive audience, as well as a sizable Non-Resident Indian (NRI) following.

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At Coutts, NRI wealth makes up roughly 20% of Asia assets under management but accounts for almost 30% of revenue in Asia.

WSJ: Banks Woo Indians Living Abroad

The bank, formed when OCBC in 2010 bought ING's Asia private- banking business, has increased its NRI assets under management by 20% annually.

WSJ: Banks Woo Indians Living Abroad

"We still have a nice book of NRI clients and we want to grow this business, but we won't be as aggressive as the commercial banks, " said Mr. Kong.

WSJ: Banks Woo Indians Living Abroad

In addition, NRI business tends to bring in higher revenue than average, because, unlike Mr. Thadani, many other nonresident Indians are very active managers of their portfolios, private bankers say.

WSJ: Banks Woo Indians Living Abroad

Coutts has beefed up its non-resident Indian team in the past half-year with six new hires in Dubai, London and Singapore, bringing the bank's NRI team to 60 including support staff.

WSJ: Banks Woo Indians Living Abroad

Private bankers say NRI clients now typically hold assets with two or three banks, compared with before the financial crisis when four to five banking relationships or more wouldn't have been unusual.

WSJ: Banks Woo Indians Living Abroad

"We have come across a number of cases where organised gangs - comprising property dealers and maybe a few government revenue officials or police department personnel - may be involved, " says Inspector General Gurpreet Deo, who is responsible for NRI (Non-Resident Indian) affairs in Punjab.

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