With the notable exceptions of Donald Trump's hair and Nick Clegg's electability, most things tend to change.

Where once partnership and the keys to the executive bathroom were all any aspiring lawyer wanted from life, now it's not quite so cut and dried. Legal Week's study of 2014′s round of partner promotions may show that the number being made up has increased significantly on last year, but a quick look under the bonnet shows that the topline figures don't tell the full story.

For one, the total promotions are not a great deal more than they were in 2012, before a notable slump the following year. More significantly, the size of the firms in question has grown markedly in the last two years, meaning that more new partners should, in theory, be making the grade to replace those leaving at the other end of the career lifespan.

But with the new partners at the top 50 UK firms making up just 4% of their combined partnerships, there may not be enough young talent coming through the ranks. While it would be wrong to draw conclusions on the basis of one year's results, there is a sense that something interesting might be happening: that the golden ticket to partnership has begun to lose its lustre.

The evidence is compelling. The traditional law firm model of a tight all-equity partnership in which all members have some skin in the game and, therefore, a sense of collective responsibility, has been steadily eroding over the last generation or so. Instead, the globalisation of many top firms has spawned myriad ways to cut the partnership cloth. Kirkland & Ellis' 'up or out' model may be at the more extreme end, but there are plenty of other firms that maintain a sizeable cohort of non-equity partners, with a status barely above that of a senior associate.  

Meanwhile, the recent reforms from HM Revenue & Customs – requiring firms to pay national insurance contributions for any 'partners' who could be considered employees – have further muddied the water. Some firms have responded by asking junior partners to increase contributions. Given that many 30-somethings will be looking to make partner at the same time as they start a family or move home, the prospect of making the grade becomes even less appealing.

Throw into the mix the fact that in-house teams are growing – both in size and influence – and it should be no surprise that lawyers are considering their options, even when the keys to the door are within their grasp.

For more, see Following an uncertain path – analysing 2014′s UK top 30 partner promotions.

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