Information and records on the Chinese companies that produce almost all of Ivanka Trump's eponymous fashion line has been increasingly difficult to obtain in the six months since the First Daughter assumed a role in her father's administration.

An investigation into the Ivanka Trump supply chain revealed that there is no way of determining what companies are exporting 90 percent of Ivanka's line into the United States from China.

That is an astonishing increase from 2014, when there was only missing data on 5 percent of the company's Chinese suppliers.

And Ivanka and her brand are keeping quiet on the matter, refusing to comment or disclose any information about the supply chain that keeps their clothing, handbags, shoes and jewelry stocked in American department stores including Dillard's and Macy's.

Ivanka's leading role as a conduit for officials from China began even before she took on an official White House role, with Ivanka rolling-out her Mandarin-speaking daughter Arabella back in February for a celebration of the Chinese New Year at their embassy in Washington DC.

The two were the guests of Ambassador Cui Tiankai at the event, and the next morning Ivanka posted a video of Arabella performing a traditional Mandarin song.

Ivanka's husband Jared Kushner meanwhile was heavily involved in the recent trade talks between China and the US just this past July.

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Bodak black: There is no information on 52 of the 57 companies that are making and exporting Ivanka Trump's fashion line into the United States from China (Ivanka above last week in DC)

They went to Jared: Ivanka's husband Jared Kushner is very involved with US-China relations, having been a key player in trade talks between the nations in July (Kushner above with Wilbur Ross, Steve Mnuchin and Chris Adams)

The company also took a silent approach after allegations emerged of low pay, excessive overtime, crude verbal abuse and possible misuse of student labor at one of the Chinese factories distributing the brand.

There was also no comment in August when it was revealed workers producing the line in another Chinese factory were reportedly being paid $62 for a 60 hour week.

That low pay comes as Ivanka Trump line posted a $17.9 million increase in net sales for the year that ended January 31, and a 332 percent increase in sales for the months of January and February.

There is already possible cause for concern about two of the suppliers that could be identified meanwhile, with one possibly in violation on the Global Fair Trade Act and another having been owned by the Chinese government.

This lack of disclosure by Ivanka and executives makes it difficult to understand whether foreign governments - in this case China - could possibly use the ties her business has to their countries to try to influence the White House.

It also makes it impossible to determine whether Ivanka's company might stand to profit from foreign government subsidies that could destroy American jobs.

These problems are even more pronounced in China due to the fact that state-owned and state-subsidized companies dominate large swaths of commercial activity.

'There should be more transparency, but right now we do not have the legal mechanism to enforce transparency unless Congress requests information through a subpoena,' said Richard Painter, who served as chief White House ethics lawyer for George W. Bush, and is part of a lawsuit against President Donald Trump for alleged constitutional violations.

'I don't know how much money she's making on this and why it's worth it. I think it's putting our trade policy in a very awkward situation.'

Live for the applause: The First Daughter has been a key conduit to China for the administration even before she became an adviser, attending a New Year's event in February (above with daughter Arabella and their host Ambassador Cui Tiankai)

Stage mom: Ivanka posted a video of her Mandarin-speaking daughter Arabella singing a traditional song the day after the New Year's celebration (above)

A review of available records about Ivanka's China supply chain found that in one instance, a province in the eastern part of the country announced the award of export subsidies to a company that shipped thousands of her eponymous handbags between March 2016 and February of this year.

Those public records, which were obtained in China, suggest a possible violation of global fair trade rules according to trade experts.

It was also discovered through public records and trade data that tons of Ivanka Trump clothing were exported from 2013 to 2015 by a company owned by the Chinese government.

It is unclear whether the brand is still working with that company, or any other state-owned entities at this time.

Zhejiang Tongxiang Foreign Trade Group Co. Ltd., a sprawling conglomerate once majority-owned by the Chinese state, sent at least 30 tons of Ivanka Trump handbags to the U.S. between March 2016 and February.

Four trade experts in the United States and China said the Zhejiang measures appeared to violate World Trade Organization rules.

'These are clearly export subsidies,' said Gary Hufbauer, a trade expert at the Peterson Institute for International Economics in Washington.

Zhejiang province's Department of Commerce and the Zhejiang Tongxiang Foreign Trade Group declined comment.

It was also discovered that from October 2013 to January 2015, Jiangsu High Hope International Group Corp., a conglomerate majority-owned by the Jiangsu provincial government, shipped 45 tons of Ivanka Trump clothing to the U.S., according to records from ImportGenius and Panjiva.

President Donald Trump has called companies that benefit from foreign government subsidies 'cheaters.'

Ivanka and her brand have pledged to avoid business with state-owned companies now that she's a White House adviser, but at the same time contends that its supply chains are not its direct responsibility.

Ivanka Trump's brand doesn't actually make its products directly, choosing to instead draw up contracts with licensees who oversee production of the merchandise.

Those licensees in turn pay the brand royalties.

The clothing, footwear and handbag licensees contacted during the investigation also declined to reveal source factories, falling silently in line with Ivanka and her brand executives.

Ivanka has been faulted many times for outsourcing the production of her company's branded goods to Chinese factories with questionable working conditions.

On Tuesday, Democratic National Committee spokesman Daniel Wessel cited the lack of information about the company's China dealings to argue that the secrecy around her brand's subcontracting relationships could conceal potential conflicts of interest.

'What we don't know is the extent to which foreign governments could use, or are already using, her business ties to try to influence the White House,' said Wessel.

Silent all these years: The company kept quiet after allegations of low pay, excessive overtime, crude verbal abuse and possible misuse of student labor at one of the Chinese factories distributing the brand (workers at the Huajian shoe factory in September 2016 above)

Making bank: That low pay comes as Ivanka Trump line posted a $17.9 million increase in net sales for the year that ended January 31 (Ivanka coats on sale in NYC)

Abigail Klem, president of IT Operations LLC, which manages Ivanka Trump's brand, said the company does not contract with foreign state-owned companies or benefit from Chinese government subsidies.

At the same time she did state that licensees of the line could possibly use those suppliers.

'We license the rights to our brand name to licensing companies that have their own supply chains and distribution networks,' explained Klem said in an email.

She then claimed: 'The brand receives royalties on sales to wholesalers and would not benefit if a licensee increased its profit margin by obtaining goods at a lower cost.'.

Michael Stone, chairman of the global brand licensing agency Beanstalk, dismissed Klem's claims and said lower production costs for licensees would ultimately benefit Ivanka Trump by freeing up money for marketing or lower retail prices, both of which drive sales.

'It gives her a competitive advantage and an indirect benefit to her financially,' said Stone.

'The more successful the licensee is the more successful Ivanka Trump is going to be.'

Records show that 85 percent of shipments of Ivanka Trump goods to the U.S. this year originated in China and Hong Kong.

The companies that shipped Ivanka Trump merchandise to the U.S. are listed for just five of 57 shipments logged by Panjiva from the end of March through mid-September.

Panjiva collects this data from US Customs and Border Protection, which did not immediately release the missing data for the other 52 shipments.

While in many cases the manufacturer ships goods directly, merchandise can also be made by one company and shipped by another trading or consolidation company.

This means that only 9 percent of the companies exporting Ivanka Trump products into the country are known, down from 27 percent.

Meanwhile, 95 percent of the companies were named in 2014, the year before her father announced he was running for office.

The brand declined to comment on the growing murkiness of its supply chain.

Chris Rogers, an analyst at Panjiva, said any company can ask customs authorities to redact its information for any reason and that about a quarter of companies request anonymity.

He then added however that the majority don't mind disclosing who they're doing business with.

'A lot of companies have said, "yes there might be a commercial disadvantage, but we want to be transparent about our supply chain,"' explained Rogers.

"'Why would we want to cover up the fact that we're working with this particular company?'"

Ethics lawyers may see disclosure as the best antidote to conflicts of interest whiel brands see it as a tool to keep supply chains scandal-free.

Public outcry over sweatshop conditions and worker suicides prompted companies like Nike and Apple to disclose the names and addresses of their manufacturers.

That in turn set an example for other companies including Gap, H&M Group, New Balance, Adidas and Levi Strauss & Co., who are also now publicly identifying their suppliers.

Allen Adamson, founder and CEO of BrandSimple Consulting, said Ivanka soul;d do the same.

'It's a missed opportunity to lead by example,' he said.

High Hope said it had 'a small number of business dealings' with Ivanka Trump licensee G-III Apparel, but declined to answer questions about whether the relationship is ongoing.

G-III, which is based in New York City, declined to respond to specific questions but said in a statement that it is 'committed to legal compliance and ethical business practices in all of our operations worldwide.'

Ivanka Trump licensee Mondani Handbags & Accessories Inc., also headquartered in New York, did not respond to requests for comment.

Ivanka Trump's brand said it was in the process of reviewing its supply chains with the help of 'independent experts whose mission it is to advance human rights' and emphasized that all licensees, manufacturers, subcontractors and suppliers are required to abide by the law, as well as ethical practices set forth in a vendor code of conduct.

The company also declined to provide a copy of it code of conduct.