UPDATE 1-Rabobank weighs bids for asset manager Robeco -sources

* Advent/CVC, AMG/Permira and Japan's Orix bid -sources

* Seller Rabobank evaluating the offers for Robeco -sources

* AMG/Permira plan to split up Robeco -sources

* Robeco could fetch more than 2 billion euros -sources

(Adds details) By Simon Meads and Jessica Toonkel LONDON/NEW YORK, Oct 10 (Reuters) - Dutch bank Rabobank

is weighing three offers for its asset management arm Robeco, facing a choice between bids to split the 2 billion euro-plus ($2.6 billion) business or sell it in one piece, people familiar with the situation said.

The Netherlands' largest retail bank received bids from a private equity consortium of Advent International and CVC , and a second from Japanese financial services group Orix for the asset management unit.

It received a third bid from Boston-based asset manager AMG Inc , which in partnership with buyouts firm Permira

plans to split up the business that spans Europe and the United States, the people said.

Rabobank is in talks with various bidders and is currently evaluating the offers, one of the people said.

The cooperative bank kicked off the sale of Robeco early this year, after it lost its triple-A credit rating from Standard & Poor's and sought to prepare for stricter capital rules on European banks.

Initially valued at less than 2 billion euros, price expectations have soared, with one source believing the firm could fetch as much as 3 billion euros.

AMG's bid with Permira could see the asset manager take on Robeco's U.S. divisions, such as Chicago-based Harbor Capital Advisors and Robeco Investment Management, with offices in New York as Boston, two of the people said.

Permira would then pick up the group's European assets such as Corestone and SAM Sustainable Asset Management in Switzerland and Robeco Institutional Asset Management headquartered in the Netherlands' second city Rotterdam.

Rabobank and Robeco declined to comment. The named bidders also declined to comment or were unavailable for comment.

(Additional reporting by Sara Webb in Amsterdam; editing by Douwe Miedema)

((simon.meads@thomsonreuters.com)(+44 20 7542 9969)(Reuters Messaging: simon.meads.thomsonreuters.com@reuters.net))