"Wishing a very happy birthday to The Duchess of Sussex today!"
He added that the decision to keep the identity of the friends anonymous was an interim one.
The full trial is not expected until next year.
On August 5, the High Court ruled in favour of the former Suits star, protecting the identities "for the time being, at least".
"The duchess felt it was necessary to take this step to try and protect her friends - as any of us would - and we're glad this was clear", said a source close to Meghan, speaking on condition of anonymity.
The judge said: 'This is an unusual case, the roles are reversed.
It's been a hard year for the royal couple following their split with the British royals, Meghan's lawsuit against Associated Newspapers over their publication of parts of a letter she sent to her father Thomas Markle Snr in 2019, and criticism over the book Finding Freedom: Harry and Meghan and the Making of a Modern Royal Family due out on August 11.
News reported. The new developments come a month after Meghan filed an application to withhold Associated Newspaper (The Mail on Sunday's parent company) from publishing the names of the five friends who spoke to People magazine.
However, ANL won the first hurdle in the legal action on May 1, when Mr Justice Warby struck out parts of Meghan's claim, including allegations that the publisher acted "dishonestly" by leaving out certain passages of the letter.
Meghan, 39, maintains that she had no prior knowledge that any of them had spoken to People magazine until after it was published.
Justin Rushbrooke QC, representing the Duchess, said in written submissions to the court: "To force the claimant, as the defendant urges this court to do, to disclose their identities to the public at this stage would be to exact an unacceptably high price for pursuing her claim for invasion of privacy against the defendant in respect of its disclosure of the letter".