Northrop Grumman (NG) won the LEM-V contract in 2010, they had already asked Hybrid Air Vehicles (HAV) to design the airframe, engine installation and propulsors, whilst NG did the mission payload, ground control station and overall project management.
From Wikipedia
https://en.wikipedia.org/wiki/Hybrid_Air_Vehicles_HAV-3:
Northrop Grumman's subcontractors included:
- Hybrid Air Vehicles Ltd. in Cranfield, UK (HAV304 platform)
- Warwick Mills in New Ipswich, USA (Fabrics engineering)
- ILC Dover in Kent County, USA (Airship manufacturer and designer)
- Textron subsidiary AAI Corp. in Hunt Valley, USA (Makes the US Army’s OneSystem UAV/surveillance aircraft control & information distribution stations); and
- SAIC in McLean, USA.
The envelope was made by an American manufacturer to HAV's design, whilst the final assembly was done in the USA because the customer was there and it didn't make sense for the bits to be going backwards and forwards across the Atlantic.