Wall Street banks are reportedly assisting Syngenta Group with its 65 billion yuan ($9 billion) Shanghai IPO by courting foreign investors.

This year, the Chinese-owned seed giant Syngenta received regulatory approval for the world's most significant potential stock market listing.

For the IPO, banks like Citigroup Inc., JPMorgan Chase & Co., HSBC Holdings Plc., and UBS Group AG are reportedly working to attract foreign investors, including cornerstone buyers. According to sources who declined to be named because the information is private, the advisers have contacted sovereign wealth funds in places like Europe and the Middle East to assess their interest.

The sponsors of Syngenta's IPO are China International Capital Corp. and BOC International Holdings Ltd. Even though some of the foreign banks might not have official roles, the sources claimed that if they are successful in attracting some investors, they will probably be given junior roles in the offering.

The people claimed that the terms of the share sale, including the bank roster, could still change because talks are still in progress. Requests for comment were not immediately answered by an HSBC representative. Citi, JPMorgan, UBS, and Syngenta representatives declined to comment.

For international banks that have been attempting to break into China's $10 trillion equity market for years, taking part in Syngenta's IPO — likely the largest in the world this year — would be a major success. Local banks and brokerages have dominated the domestic IPO market, taking the top 20 spots in the league table rankings, according to data gathered by Bloomberg.