The Duchess of Sussex rose to fame as Meghan Markle - but her latest social media venture, an online shop selling 'handpicked and curated collection of the things I love', appears to confirm that her initials are no longer 'MM'.
The former Suits actress, 43, who launched her new business venture on both her personal and official As Ever Instagram pages this week, has been the Duchess of Sussex since her wedding to Prince Harry in 2018, but still widely known by her maiden name of Markle.
Seven years on, and it seems the name of the English region, which the couple visited together just once while living in the UK, has finally become the family's permanent surname.
The latest clue? Meghan's initials on the website address to her new retail window are listed as 'MS' not 'MM', with the full URL reading 'shopmy.us/ms'.
The former royal, who resides in an £11million property in the swish Californian enclave of Montecito with Prince Harry and their children, Archie and Lilibet, appeared to begin making people aware of how she'd now like to be referred to in her recent Netflix series, With Love, Meghan.
She told writer and comedian Mindy Kaling during one episode, in which the friends made a fruit platter and star-shaped sandwiches: 'It's so funny you keep saying Meghan Markle, you know I'm Sussex now'.
'Well, now I know,' Mindy replied, 'and I love it.'
US actor and chat show host Drew Barrymore also introduced the former royal on her show recently as 'Meghan Sussex'.
And the Duchess of Sussex further emphasised the meaning behind her last name in a recent interview with People Magazine.
'I love that that is something that Archie, Lili, H and I all have together,’ she said. ‘It means a lot to me.’
Harry and Meghan were first bestowed their titles as the Duke and Duchess of Sussex after they wed in 2018.
They have only ever officially set foot in the region, which lies south of London on the English south coast once - for just six hours - after a whistle-stop tour in the October following their wedding.
Meghan's Instagram site was launched at the start of the year in advance of her 'With Love, Meghan' lifestyle programme and her soon-to-come As Ever range of merchandise.
One of the reasons Meghan and Prince Harry parted ways with the Royal Family was the monarchy's refusal to accept commercial endorsements by the couple.
Under the terms of Harry and Meghan's agreement with Buckingham Palace when they acrimoniously quit royal duties, there is nothing to stop her selling products as long as she doesn't nakedly cash in on her royal links.
However, it is notable that the new scheme has been launched using her full title, Meghan, Duchess of Sussex.
In a recent episode of Palace Confidential, The Mail's Diary Editor Richard Eden described Meghan's announcement that she has taken the name Sussex as one of the few 'genuinely interesting' parts of her new Netflix series.
'That was news to all of us because we didn't realise that they were using those titles,' the royal expert said.
'Archie and Lilibet, on their birth certificates it says Mountbatten-Windsor which is the Royal Family surname but since they became the Duke and Duchess of Sussex, the family can also use the Sussex title.
'They have obviously chosen to use the Sussex name in the same way that Harry used to be known as Harry Wales when he was in the Armed Forces.'
Throughout his time at Eton, the young prince was referred to as Harry Wales - a nod to his father's title as Charles, the Prince of Wales.
And while serving as a helicopter pilot in the Army, he was known as Captain Harry Wales. Members of the Royal Family - indeed, the peerage generally - often use their dukedom or title as a 'shorthand surname'.
But the couple's real names, Henry and Rachel, are still used on official documents, including their marriage certificate.
Signed by the ex-Archbishop of Canterbury Justin Welby, it declares that 'HRH Prince Henry of Wales' married 'Rachel Meghan Markle' on May 19, 2018, 'in the Queen's Free Chapel of St George'.
Their first-born's last name was also recorded as 'Mountbatten-Windsor' - the official last name of the Royal Family - rather than 'Sussex'.
In a recent article, the Mail's Royal Editor Rebecca English explained why that is so: 'This dates back to 1960 when Queen Elizabeth and the Duke of Edinburgh decided they would like their own direct descents to be distinguished from the rest of the Royal Family, without changing the name of the Royal House (which had been Windsor since 1917, after George V anglicised the name from Saxe-Coburg-Gotha as a result of anti-German public sentiment).
Meghan Markle will 'make a killing' off fans with her new Instagram shop
'And so it was declared in the Privy Council that the Queen's descendants would add a hyphenated "Mountbatten" to reflect Prince Philip's surname, which he himself took on in 1947 when he became a naturalised Briton.'
However, members of the Royal Family entitled to the style of HRH Prince or Princess often opt to use their title as a shorthand surname instead.
Prince William, for example, has also always used the named Wales, and his children are simply known as George Wales, Charlotte Wales and Louis Wales at school.
Before they got married, Princess Beatrice and Princess Eugenie also used the surname York, taken from their father, Prince Andrew, the Duke of York.
It is, therefore, not surprising that Harry, Meghan, Archie and Lilibet would be known as Sussex.
Wendy Bosberry-Scott, editor of Debrett's Peerage and Baronetage, said: 'The official surname of the Royal Family is Mountbatten-Windsor.
'However, it has long been the practice of the Royal Family, and indeed the peerage, to use a title as a surname where one is available.
'Now that he is the Duke of Sussex, it is perfectly within protocol for him to use Harry Sussex and for his wife to use Meghan Sussex.
'This is no different from the Duke of Norfolk calling himself Edward Norfolk, when his surname is Howard.'
Meghan, who stepped back from frontline royal duties alongside her husband in 2020, unleashed her latest business idea this week, writing over a screen-recorded video of her new online store: 'Many of you have asked, so here you go! A little shopping to start the week.'
The ShopMy site features 32 items 'curated' by the duchess with 'affiliated' links to the brands' websites.
While there are a few affordable items, including a £99 Uniqlo trenchcoat, many seem way out of the average shopper's budget. Others appear to shamelessly highlight her royal links or endorse her well-connected friends' ventures.
'She could potentially earn millions from this and is probably earning a commission on every sale she makes,' money and business coach Maddy Alexander-Grout told MailOnline.
She added: 'If you take on average how many followers she has (2.6 million) and how much engagement she has, I would imagine based on her following that she will have thousands and thousands of people buying these things and she will be making a fair amount of that.
'She is going to make a fair amount based on what the clothes are worth. If she gets say 15% off a shirt that's £128, she will be making £19.20. She will be selling thousands of those and could be making at least £19k from one linen shirt.'
One of the most expensive items on her ShopMy site is a £1,070 ivory 'Windsor' Heidi Merrick gown – the name of the royal estate in Berkshire where she and Prince Harry married and once lived.
Then there are the Ariel Gordon £215 'royal signet' stud earrings and a £595 pair of tan Saint Laurent slides.
