Michelle Madsen talks to Wolf von Kumberg, European legal head at one the world's largest defence companies

The only indication that the modest office in St James's is home to one of the world's biggest defence companies is a few glossy prints of satellites, rockets and military aircraft on the walls.

In all other respects, Northrop Grumman's London office is just as understated and unassuming as Wolf von Kumberg, the company's European legal director, who runs its small regional legal team of eight lawyers and support staff from the UK.

Working for a company that sells defensive radars, amphibious assault ships and cutting-edge satellites to governments around the world might suggest to some glamorous connotations of spy scandals, diplomats and arms dealers, but von Kumberg takes it all in his stride.

"Given the sort of products we are creating, it is not surprising that we work in a secretive culture. I do visit some of the manufacturing plants but there is a lot of stuff I do not know about – stuff that is classified," he comments.

One such formerly top-secret project is the distinctive bat-winged B-2 stealth bomber, which at $2.2bn (£1.1bn) each is one of the most expensive planes ever built. Northrop Grumman's most iconic innovation cemented the $30bn (£15bn) company's place as one of the world's largest and most influential defence contractors after fellow US giants Boeing and Lockheed Martin.

Von Kumberg is a veteran of the defence industry, having first made the move in-house from his former role as a litigator at Toronto law firm Smith Lyon to legacy US military and commercial manufacturing company Litton in 1987. After a five-year stint as Canadian counsel for the company, von Kumberg jumped at the opportunity to take on the role of European legal director.

When von Kumberg arrived in Switzerland in 1992 he inherited a team of just three lawyers, all located centrally in Zurich. Realising that the department needed a shake-up, he took on an entirely new team and restructured the department.

"When I came over, the team had a very old-fashioned structure. The lawyers were not out in the field, although Litton had decentralised in North America. As it happened, they were all retiring at around the same time I began, so we made the move to hire local lawyers and embed them in the businesses in Germany, France and the UK. Now we have four lawyers in Europe and a paralegal – it is still a pretty slim structure."

After Northrop Grumman bought out Litton in 2001, von Kumberg decided to stay and take on the newly-merged company's expanded European legal remit. One of his first major tasks for Northrop Grumman was advising the company on its $5.9bn (£2.9bn) acquisition of aerospace and automotive product company TRW in 2002, on which he worked closely with a team at Freshfields Bruckhaus Deringer monitoring the spin-off of TRW's automotive business.

Freshfields is just one of a large informal roster of advisers von Kumberg has built up a relationship with over the years. He admits that until recently, when employee benefits work was put out to tender, the company had never run a procurement exercise for outside counsel in Europe.

"Most strategy is formulated in the US but we do get very involved in European transactions, which is why I like to build close relationships with our outside counsel," says von Kumberg. "I like to be flexible in who I instruct. If it is a big enough deal I am usually able to negotiate a price and then I can choose a firm for that particular transaction."

Von Kumberg's personal method of dealing with the procurement of outside counsel is a contrast to the more systematised method used by his counterparts in the US, where all work is processed centrally and given a billing number to allow the company to keep tabs on its external legal costs.

"In Europe we do not have that sort of sophistication," he explains. "The sort of issues that we deal with over here, such as export regulations, are speciality areas. Our approach works because Northrop is involved in very specific business areas – we deal with governments, not consumers, which explains why we have a smaller legal team. We also rarely get embroiled in litigation – there are lots of things you simply cannot make public and governments classify information."

Some areas of the arms industry are, however, open to public scrutiny, as current investigations into BAE Systems' alleged bribery of Saudi royals would suggest. This situation is, according to von Kumberg, one that US defence companies are unlikely to face having been subject to stringent regulation in the shape of the Foreign Corrupt Practices Act since 1977.

"The regulatory climate in Europe is quickly changing and catching up with that of the US," says von Kumberg. "Since the 1970s, US legislation has prevented US companies paying bribes for contracts. Companies in the European Union (EU) are now being subjected to similar standards as those imposed on their US counterparts but you have to remember that EU countries only signed up to similar legislation in 2002.

"There is a key lesson to be learnt as European defence contractors enter into a linked strategy through acquisitions they subject themselves to US scrutiny by the Department of Justice – this is a side effect of expansion."

Tackling Europe's increasingly heavy-handed regulatory climate is something that von Kumberg will not have to deal with alone, having set up a networking group of aerospace lawyers with Bird & Bird partner and former BAE Systems in-house lawyer Paul Briggs. The group, which meets on a semi-annual basis, comprises senior lawyers from 20 aerospace companies including industry stalwart Andrew Gallagher from BAE Systems, and members of EADS' and Tollis' in-house teams.

"The idea is that we have a confidential forum to discuss issues that are familiar to those in the industry," he says. "We all knew different people and invited along other friends in the industry, but we are trying to keep it as senior as possible."

"As senior as they come," is how one of von Kumberg's peers describes him, saying that he captures the spirit of the industry and is looked to as a mentor by other lawyers in his field. Von Kumberg says that it was his experience as a litigator more than anything else which equipped him with the tools for the job.