56-year-old Greg Agnew found a loophole that he says got him an invite to one of the most exclusive events in London – a garden party with the Queen, Prince Philip, Kate, and Will at Buckingham Palace.

Agnew, an investor in companies like Apple, Google, and Facebook and a former journalist who lives in Los Angeles, is originally from New Zealand. He said: "I discovered this strange little loophole that I think was created in Queen Victoria's time."

"Anyone with a New Zealand passport can simply request an invitation. I did that and they said yes. It was that simple."

The option appears to also exist for other countries like Australia.

This is the invite Agnew says he received for the party, which took place on Tuesday May 16, after simply applying through New Zealand Foreign Affairs & Trade.

Agnew and his wife Nicole, an American citizen, travelled to London for the event. Nicole was Greg's plus one.

On the day of the party, they went to New Zealand House in Trafalgar Square, showed their passports, and were given their tickets.

"For British people, it would have been more difficult to get in," he said. "There are all of these laws over the years and nobody ever moves them, they still exist."

The official Royal Family website states that: "It is not possible to acquire invitations to The Queen's Garden Parties through direct application to Buckingham Palace," adding that "a long established network of sponsors is used to invite guests, who include Lord-Lieutenants, Societies and Associations, Government Departments, Local Government, the Services, the Church and other Faiths. They nominate guests for invitation and we hope in this way to achieve a representative cross-section of the community."

They showed up at Buckingham Palace early. "The gates technically open at 2 p.m., but there's a large crowd of people so it takes quite a bit of time to get in," Agnew said.

There were three entrances to choose from. "We chose the front gate entrance. We assembled at the gate, went past police security, and had our identification and invitation checked."

"We went through the gates to the gravel area in front of the palace, then walked through Buckingham Palace into the courtyard. It was a great way to see inside the palace."

He added that "they were very strict about no photos inside the palace" but they saw grand staircases and "hundreds of paintings" before making their way out through the "grand steps" at the back of the palace.

"That's where you can see the Queen's gardens, and the giant lawn at the back with a tent for food and drinks."

"There were two different tents with two different bands at the front and the rear."

"To the right of the band at the rear, there was a diplomat and foreign leaders area, which was slightly roped off."

"You enter and mingle, and everyone is taking photos. They didn’t try to police photos."

Agnew said that the officially starts at 3 p.m, and at 3.30 p.m. the staff started to "place people who have been chosen to talk to the Queen and Will and Kate strategically in a line so they get to talk one by one." They also briefed them on how they should act around the Royal Family.

At 4 p.m., God Save the Queen was played, and Her Majesty Queen Elizabeth II came out with Prince Philip.

Then Will came out...

...followed by Kate. Other members of the Royal Family followed.

"They stand in a straight line, come down one at a time, then beeline for the people who have been allocated for them to talk to," Agnew said. "It's extremely well organised."

"Each person has at least one handler who briefs them on every person they’re going to talk to."

"There’s no obvious security or crowd control, people are very well behaved," Agnew said. "It's very casual, you walk amongst them, they're very friendly. Prince Philip was very generous with his time, talking to people, laughing, giving them lots of time and attention."

At about 5 p.m., the royals headed to the diplomats' area and "focused on the people there."

At 5.30 p.m., they went to the Royal Tea Tent to drink their tea while the crowd watched.

The guests also headed for refreshments.

On offer were finger sandwiches, wraps, salmon blinis, fruit cake, tarts, and eclairs, as well as tea, iced coffee, or apple juice.

At 6 p.m. the royals went back into the Palace, but guests were told they could stay and enjoy the gardens, which Agnew says includes a "pond with geese, stone bridge, and a semi-wilderness 'like if no one was living there.'"

"It was never that crowded," he added. "They've sorted out how to invite the right number of people."

A former journalist and investor in cloud and tech companies who he says include Apple, Google, and Facebook, Agnew said that being in London, where he has been a "dozen times" for work, meant something special to him.

"I covered plenty of things in London including Princess Diana’s death, which made this kind of special, with it being the 20th anniversary," he said.

He called the party "the experience of a lifetime."

Greg Agnew and his wife, Nicole. Greg Agnew

"I was extremely impressed," he said." I loved the fact that especially in this time of high security they gave us absolute freedom. We felt very welcome and as if it was their pleasure to have us all there."