Take a look at the slick literature that Allen & Overy and Shearman & Sterling have put out on their merger announcement, and you’d think it’s set in stone—a bespoke website, complete with FAQs, formidable stats on the combined firm, an upbeat video interview featuring the respective firms’ leaders.

But, as one partner on the inside put it, “It’s far from a done deal, so it is a risk, yes”. Like with any M&A deal, there is “always a chance that you won’t get shareholder approval”.