A copy of the birth certificate shows Harry used "The Duke of Sussex" as his first name and "His Royal Highness" as his last name. In the document, obtained by The Sun, the Duchess of Sussex's name is listed as "Rachel Meghan Markle".
A birth certificate is a public document in the US state of California, where Harry and Meghan have set up home after quitting royal duties last year.
As part of Megxit, the Sussexes kept their HRH styles but agreed not to use them.
However, they still use their Duke and Duchess titles, which were a gift from the Queen on their wedding day.
The couple's daughter Lili was born on June 6 at Santa Barbara Cottage Hospital.
Harry and Meghan sparked controversy with their name choice, with Lilibet being the Queen's childhood family nickname.
It has been widely reported that the pair did not ask the monarch before deciding on the name.
But a spokeswoman for the couple insister their daughter's moniker was mentioned by Harry in a conversation with the Queen and "had she not been supportive, they would not have used the name".
The Sussexes' lawyers wrote to the BBC after the corporation claimed in a report that Her Majesty had not been asked about naming their baby Lilibet.
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11.40am update: Meghan and Harry cut-off claims show pair 'out of touch'
Meghan Markle and Prince Harry's claims that the Royal Family financially cut them off has been criticised by an Aussie TV host who called the couple "out of touch".
Edwina Bartholomew said: "There seems to be some kind of argument over the timing, so I don't think they outright told a lie."
"I do think it makes them look even more out of touch, when you're talking about gazillions of dollars."
11.10am update: Harry and Meghan teased by football club for rejecting Dumbarton title
Prince Harry and Meghan Markle have been teased by a football club after reports they rejected the Earl of Dumbarton title for Archie because it contained the word "dumb".
Dumbarton FC took to Twitter to poke fun at claims the Duke and Duchess of Sussex turned down the Scottish title for their son.
They shared a hilarious meme of five figures dressed as clowns and dunces with "we will not be dumb" written on a blackboard behind them.
The football club joked in the caption: "No offence taken @RoyalFamily."
Dumbarton FC's tweet comes after reports Harry and Meghan rejected the title over fears Archie would be bullied.
10.25am update: Meghan ditches royal title on Lilibet Diana's birth certificate
Meghan Markle ditched her royal title on the birth certificate of Lilibet Diana.
The Duchess of Sussex used Rachel Meghan Markle for her daughter's birth certificate.
This marks a contrast to the birth certificate of Archie Harrison, where Meghan's royal title was included.
9.45am update: Harry and Meghan honoured in Royal Family exhibition despite quitting
Prince Harry and Meghan Markle feature in a new Royal Family exhibition despite their decision to quit the Firm.
Harry and Meghan's relationship with Royal Family has been tense ever since the couple lifted the lid on their time as senior royals during their TV interview with Oprah Winfrey in March.
But despite the Sussexes having quit the Firm in March 2020 and their ongoing rift with the Palace, they are still honoured in a new exhibition examining Britain's monarchy.
9.25am update: Should William and Harry finally resolve feud at Diana event?
Prince William and Prince Harry are due to be reunited for the unveiling of a statue dedicated to Princess Diana - so should the once-close brothers finally resolve their rift?
Vote in our poll on whether the Duke of Cambridge and the Duke of Sussex should put the feud behind them for the event in honour of their late mother.
Our poll comes as William and Harry will reunite in public for only the second time since Megxit for the statue unveiling at Kensington Palace on July 1.
8.55am update: Harry spotted leaving California for Britain
Prince Harry has left California for the UK to attend the unveiling of the statue of Princess Diana.
The Duke of Sussex was spotted arriving at Los Angeles International Airport on Thursday evening.
Harry's return comes two months after his last trip to Britain.
8.20am update: Royal Family U-turn has exposed Meghan and Harry
The Royal Family's decision to abandon the Queen's famous "never complain, never explain" mantra has exposed claims made by Meghan Markle and Prince Harry, according to a royal commentator.
Angela Levin claimed the Royal Family records that demonstrate Prince Charles did continue to fund Harry and Meghan in the immediate aftermath of their exit from the monarchy indicate the Duke and Duchess of Sussex told a "blatant lie".
The royal commentator also told talkRADIO as time goes on the Sussexes "look more and more nasty".
7.45am update: William and Harry 'forced to scrap large ceremony for unveiling'
Princes William and Harry have had to make drastic last minute cuts to their guest list for the unveiling of the statue in honour of their late mother Princess Diana, according to reports.
The two brothers had originally invited 100 of their mother's friends, supporters and former staff to the momentous event.
Pop legend Elton John and David Furnish, who contributed to the funding of the memorial, were some of the famous names due to be present.
However, Covid rules have apparently forced the brothers into a major rethink.
The event will now be attended only by the Princes and some of the Spencer relatives, according to the Daily Mail.
7.30am update: Harry blasted for 'moaning' about money
Prince Harry has been blasted for whining about money during his infamous interview with Oprah Winfrey following the publication of royal accounts.
Writing in the Telegraph, commentator Robert Taylor said: “Is there anything more unseemly than rich people complaining about money?
“By any normal standards, Harry and Meghan are super-wealthy. They have an estimated joint worth of nearly £10million, and live in a luxury pad in California overlooking the Pacific. They mix with millionaires and billionaires.
“Yet Harry saw fit to moan, in that blockbuster interview with Oprah, that his father had ‘literally’ cut him off.”