HNA Group Co. disclosed it's controlled by a couple of charities as the acquisitive Chinese conglomerate whose overseas investments have come under scrutiny seeks to dispel concerns about its ownership structure.

Two charities named Cihang -- one based in New York and the other in the resort island of Hainan -- own 52 percent of HNA Group, according to a company statement on Monday. Twelve HNA officials including founders Chen Feng and Wang Jian hold about 47.5 percent, with the rest held by Hainan Airlines Holding Co., according to the statement.

The statement represents HNA's most detailed disclosure about its ownership and comes as the group faces increasing scrutiny -- and as it tries to purchase the hedge-fund firm of White House communications director Anthony Scaramucci. Bank of America Merrill Lynch has told investment bankers to stop working on transactions with HNA for now amid growing concerns about the group's debt levels and ownership structure, people familiar with the matter said last week.

New York-based Hainan Cihang Charity Foundation Inc. owns 29.5 percent of the group, followed by China-based Hainan Province Cihang Foundation's 22.75 percent. Among the executives, Chen and Wang -- who are both co-chairmen -- hold the highest stakes with 14.98 percent each.

Little is known about how the philanthropic organizations are managed and how votes are cast, though the company says its donations have reached tens of billions of yuan.

HNA said it plans to update its ownership status annually and that the executives plan to donate all their shares to the charities should they resign or die. Eventually, HNA expects the foundations to own 100 percent of the group.

The figures differ from available data as recently as late last year, when corporate filings showed that a businessman named Guan Jun owned a 29 percent stake via two holding companies. Guan doesn't show up in HNA's latest statement.

Little is known about Guan. HNA has played down his role, with CEO Adam Tan saying he's just a Chinese businessman and Chairman Chen Feng telling the South China Morning Post newspaper that Guan isn't a significant shareholder as he only owns a "tiny" stake. Yet the corporate filings showed Guan owned a bigger stake in the group than both Chen and Tan's stakes combined.

HNA said Guan recently donated his shares to Cihang.

HNA has been under pressure lately. The group was among several prolific Chinese acquirers of foreign assets -- the others being Fosun International Ltd., Dalian Wanda Group Co., Anbang Insurance Group Co. and the buyer of the AC Milan soccer club -- whose loans have been under the scrutiny of the nation's banking regulator.

Bank of America Merrill Lynch joined other Wall Street firms that are largely steering clear of advising and financing the group on deals because they are unable to get internal approvals from "know your customer" committees, people familiar with the matter have told Bloomberg. HNA said on Saturday that its acquired companies have had business arrangements with Bank of America Merrill Lynch and that cooperation is proceeding normally.

Meanwhile, in Washington, HNA's purchase of Scaramucci's SkyBridge Capital has been delayed by the Committee on Foreign Investment in the United States, according to two people familiar with the situation. CFIUS, an interagency committee, vets sales of American companies to foreign buyers to protect national security. However, the committee, whose head is the Treasury secretary, is facing a backlog of cases because senior posts at key member agencies have yet to be filled by President Donald Trump.

At home, three Chinese banks decided to stop extending new loans to HNA and one lender reduced the size of a credit line, according to other people familiar with the matter. In response, HNA said its financial position remains "strong" and noted that its debt-to-asset ratio decreased for a seventh straight year in fiscal 2016.

HNA's ownership has also been under attack from Guo Wengui, a fugitive Chinese tycoon who's been alleging HNA has secret ties to powerful Communist Party officials -- claims denied by the company. Guo is facing defamation lawsuits from HNA and others over his various claims.