In March, palace aides approached The Times to allege that Meghan faced "a bullying complaint made by one of her closest advisers" during her time as a working royal.
Sources reportedly claimed that the duchess drove two personal assistants out of the household and undermined the confidence of a third staff member.
Jason Knauf, Harry and Meghan's communications assistant at the time, reportedly submitted the complaint in October 2018 to protect palace staff who were allegedly “coming under pressure” from the duchess.
At the time, the Sussexes released a statement in response to the allegations.
"The Duchess is saddened by this latest attack on her character, particularly as someone who has been the target of bullying herself and is deeply committed to supporting those who have experienced pain and trauma," the statement read.
"She is determined to continue her work building compassion around the world and will keep striving to set an example for doing what is right and doing what is good."
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Buckingham Palace also released a statement, claiming its HR team was taking the matter seriously.
"We are clearly very concerned about allegations in 'The Times' following claims made by former staff of The Duke and Duchess of Sussex.
"Accordingly our HR team will look into the circumstances outlined in the article. Members of staff involved at the time, including those who have left the Household, will be invited to participate to see if lessons can be learned.
The statement continued: "The Royal Household has had a Dignity at Work police in place for a number of years and does not and will not tolerate bullying or harassment in the workplace."