A mixture of profitability concerns and desire for further growth are likely to have been key factors in Bird & Bird's 20 lawyer Hamburg team's decision to move to DLA Piper last week, according to partners in the German market.

Last week it emerged that 20 lawyers, including five partners, who all previously joined from Hogan Lovells when Bird & Bird launched in Hamburg in 2011, would make the move.

The partners moving to DLA are technology, media and telecommunications partner Stefan Engels, corporate partners Jorg Paura and Daniel Weiss, litigation partner Michael Stulz-Herrnstadt and intellectual property partner Ulrike Grübler.

One ex-head of a magic circle firm's German corporate practice believes that the office's performance was a driving factor behind the move. He says: "What could they [Bird & Bird] do with 20 lawyers? It sounds a bit like a forced move.

He argues that there were "massive gaps" between the profitability of Bird & Bird's Hamburg office and the firm's London teams, that may well have contributed to the decision to move.

He adds: "Bird & Bird's German offices have been in constant reorganisation over the past decade. The firm has its stronghold in commercial law, which is an area where you can't generate that much profit in Germany. It's no wonder the re-organisation continues."

An ex-Bird & Bird partner says: "Bird & Bird's Hamburg practice came along much later than their other practices in Germany, and in a sense it was sort of self-contained."

He adds that he does not think the practice had been as "integrated as much as it could have" been with Bird & Bird's wider business.

However, one ex-German partner at a UK firm says that the move may have been motivated more by DLA trying to pull in quality lawyers rather than any issues at Bird & Bird.

He says: "I am not surprised they [the Bird & Bird team] moved to DLA. At the moment there are three firms in Germany that are being very aggressive in getting people onboard which are DLA, Dentons and K&L Gates. They are basically trying to reach out to everyone available in the market."

A spokesperson for Bird & Bird thanked the departing partners for their contribution to the firm.

She added: "Hamburg remains an important location for Bird & Bird and our clients and we will be developing it further."

The news, reported by Legal Week last week, follows a spate of partner movement in the region. Some firms, such as Clifford Chance (CC) have opted to cut back their presence in Germany – but others are continuing to push for growth in the region.

Dr Ralf Thaeter, German Head at Herbert Smith Freehill (HSF) said: "There is a lot of movement in Germany but I think the story should be told in its entirety – if offices are closing it's important to note that the teams often remain part of firms."