At face value, last week's departures of Colin Gray and Colin McKay from McGrigors to Eversheds were unsurprising. After all, the firm has lost a number of partners in recent years and this, combined with the fact Gray finished his second term as managing partner in March and that McKay stood unsuccessfully as his successor, could be seen as a reasonable explanation.

However, many of those who know the pair are more than a little surprised. As one former partner told Legal Week: "I was shocked – they were McGrigors through and through."

Their departures will be seen as not just as a blow to the firm generally but also, crucially, to its London practice – a significant loss at a time when rival Scottish firms such as Shepherd & Wedderburn are trying to grow their London presence and when Scotland's biggest banks are active in the City.

Both partners have strong ties with key clients Royal Bank of Scotland and Bank of Scotland. Real estate finance chief McKay is singled out for his transactional work, with recent deals including advising HBoS on the financing of Silvertown Quay regeneration project in London's Docklands. Granted, neither was based in the City full-time, but McKay spent much of his time in London and both were fully committed to the City. During his time leading the firm Gray wanted to tie-up with a national firm, with Eversheds rumoured as a candidate. Meanwhile, McKay's pro-London views set him aside from new managing partner Richard Masters, who some had labelled the more conservative candidate. Their departure has inevitably left many asking where the office will go from here.

McGrigors stresses that London remains a key part of the firm's strategy. It argues the office has a strong roster of FTSE 250 corporate clients and that London made up 35% of last year's overall turnover of £60m. It is already the firm's biggest office by fee earners, with a headcount of 126, and Masters stresses that he wants to double this within three years, as well as trying to find a merger target over the same period.

However, the external perception of the firm is quite different. Some say the City office started going downhill almost as soon as McGrigors emerged as an independent firm following the collapse of KPMG's KLegal network in 2004, with the firm concentrating on Scotland above London.

As one partner at a rival firm observes: "After the split with KLegal there was a clear drive towards Scotland which created a toxic relationship between the two offices. The effect it had on the London office was like turning diamonds back into carbon."

The City office has seen a number of partner departures over the last two years, including that of corporate partner David Mandell, who joined Mintz Levin's City arm last month, while a two-partner intellectual property (IP) team including national IP, IT and commercial group head Catrin Turner, left for Pinsent Masons last year. Meanwhile, a redundancy consultation is expected to affect four fee earners and five secretaries in London.

With real estate affected by the market downturn and the banking practice comprising only two permanent partners in the City, it is hard to see what strengths the office now has – outside of its tax litigation group. Add in claims of minimal City autonomy and Scottish interference as well as rumours of disagreements about remuneration for London lawyers and it is clear why many suspect London will only suffer further as a result of the latest losses, despite Masters' protests. Both were seen as integral to the office and without them it is likely that both London and the firm generally will have less direction.

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