The millions of dollars donated by foreign governments to the Clinton Foundation have boosted the couple's global reach but critics warn they ensnare the White House candidate in conflicts of interest.
During the four years Hillary Clinton spent as US secretary of state from 2009 to 2013, foreign funds continued to flow into the charity founded in 2001 by her husband, former president Bill Clinton.
To avoid the appearance of conflict of interest, the foundation agreed to curb foreign donations in a memorandum of understanding with the Obama administration.
Under the agreement, the foundation was to alert an ethics review if an existing state donor "materially" increased funds or if a new country offered funds, to analyze whether they were trying to influence US policy.
But six years later, the foundation admitted it did not pass along for state department review an unsolicited $500,000 donation from Algeria intended for Haiti after the 2010 earthquake.
- Foreign donations -
At least seven foreign states -- Algeria, Australia, the Dominican Republic, Kuwait, Norway, Oman and Qatar -- donated to the foundation while Clinton was secretary of state and in charge of sometimes sensitive diplomatic matters relating to those countries.
A number of others, such as Germany, Saudi Arabia and the United Arab Emirates donated funds in 2014, after she stepped down.
Then there are checks worth millions of dollars from company executives, philanthropists, billionaires and foreign organizations, among them the Ukranian Victor Pinchuk, the Saudi Mohammed al-Amoudi and Rilin Enterprises, which is led by Chinese billionaire Wang Wenliang, a member of the Chinese parliament.
The contributions are legal, but funds from individuals or entities that have considerable diplomatic or economic clout to defend in Washington, expose Clinton to suspicions of conflict of interest since the Democrat gains directly from the success of the foundation which has carried her name since 2013.
The Washington Post said that nearly half of the major donors who are backing Ready for Hillary, a group promoting her 2016 bid, have given at least $10,000 to the foundation.
Republicans have pounced on foreign donations as a means of attacking the Clintons, particularly the Algerian fund that escaped the ethical control standards of the state department.
- Political pressure -
Last month, Republican presidential contender Senator Rand Paul, criticized donations from the Gulf monarchies and called on the Clinton Foundation to give back the money to Saudi Arabia.
"Hillary Clinton needs to explain why she's taking money from foreign countries that abuse the rights of women," he said.
Clinton responded last month by defending the foundation's humanitarian work. "There can't be any mistake about my passion concerning women's rights here at home and around the world," she said.
"I think that people who want to support the foundation know full well what it is we stand for and what we're working on."
The foundation said in a statement that when Clinton runs for president, it would ensure its "practices regarding support from international partners are appropriate" -- just as when she was secretary of state.