By Olivia Oran

(Reuters) - Credit Suisse Group AG was the top underwriter for U.S. initial public offerings this year for the first time, bolstered by its role in helping large private equity backed companies go public.

The Swiss bank generated $4.7 billion in IPO proceeds during 2012 from 41 issues, vaulting it in front of JP Morgan Chase & Co with $4.6 billion, according to Thomson Reuters data.

Goldman Sachs Group Inc placed third with $4.5 billion, while the previously top-ranked Morgan Stanley came in fourth.

Credit Suisse was ranked eighth last year in the U.S. IPO league tables with $2.8 billion in proceeds.

"2012 was a challenging year for IPO issuances," said Joe Reece, global head of Credit Suisse's equity capital markets group. "This fact makes it even more critical to be acutely focused on clients."

Large deals the bank helped underwrite include private equity firm Carlyle Group's $671 million offering, payment processor Vantiv Inc's $575 million offering and industrial company Rexnord Corp's $426 million offering.

It also made a number of changes internally which may have contributed to its climb, Reece said.

In May, former syndicate head David Hermer was named head of equity capital markets of the Americas. The group also integrated its origination and syndicate units under one structure.

Credit Suisse is trying to build up its equity capital markets business at a time when other banks are doing the opposite.

Royal Bank of Scotland Group PLC said earlier this year it would exit its equity capital markets business, while Nomura Holdings Inc <8604.T> has also cut back in the division in Europe, Reuters has previously reported.

"There are firms pulling in and not investing in ECM. We're doing the opposite," Reece said. "We view the equity product as core to our strategy."

(Reporting by Olivia Oran; Editing by Phil Berlowitz)