Boeing Business Jets revealed the orders from unidentified "elite customers" during the European Business Aviation Conference and Exhibition in Geneva, Switzerland, over the weekend.
Boeing spokesman Dmitry Krol declined to disclose additional information about the buyers or about the aircraft involved in the two remaining orders, citing VIP customer confidentiality requirements.
The new orders this year come after members of the world's super wealthy purchased 16 Boeing Business Jets in 2017.
Boeing Business Jets leader Greg Laxton said in a statement the VIP jet unit is seeing much customer interest in Boeing's new BBJ Max, thanks to the jet family's increase range and superior fuel economy.
"The performance advantage of the BBJ MAX is a big sales driver," said Laxton. Laxton said the plan is well-suited for customers who want to fly farther without stopping.
A BBJ Max jet can fly 7,000 nautical miles and features interior options to match any customer's preference.
"Customers seek more space and greater range, which is driving significant growth in the large cabin segment," Laxton said.
The new orders give the jet maker's VIP business jet unit a backlog of 19 airplanes, helping make the BBJ Max one of Boeing's fastest-selling business jets in history.
Based on the new 737 Max airplane, the BBJ Max delivers 14 percent better fuel efficiency because of its advanced engines and improved aerodynamics.
The model also features Dreamliner 787-style flight deck displays and multiple advanced new systems, Boeing says.
Boeing celebrated the first 737 BBJ Max flight in mid-April 2018, when an unpainted green BBJ Max 8 took to the skies.
The jet maker expects additional deliveries of BBJ Max airplanes in coming months.
Base 737 Max models sell for between $96 million (a Max 7) to $130 million (a larger Max 10).
There are currently 233 Boeing BBJ aircraft in operation since the jet maker started to offer them in 1996.
(Andrew McIntosh - Puget Sound Business Journal)