The law concerning limitation periods has long been recognised to be unsatisfactory. One area which poses particular problems concerns whether a limitation period can apply to equitable claims “by analogy” under section 36 of the Limitation Act 1980. This article considers three relatively recent decisions of the Court of Appeal – P & O Nedlloyd BV v Arab Metals Co. (The UB Tiger) [2006] EWCA Civ 1717, [2007] 1 W.L.R. 2288, The Commissioners for Her Majesty’s Revenue and Customs v IGE USA Investments Ltd. [2021] EWCA Civ 534, [2021] Ch. 423 and The Claimants in the Royal Mail Group Litigation v Royal Mail Group Limited [2021] EWCA Civ 1173 – which illustrate that very different approaches have been taken. It is argued that The UB Tiger was wrongly decided, or at least should be limited to specific performance, and revives calls for legislative reform.

This paper draws on Marxist scholarship concerning the law's emancipatory potential to shed new light on the history of UK trade unions, and their relationship with law. It traces the historical development of UK trade union law from the nineteenth century to the present day with a view to illustrating the importance of considering not just the content, but also the form, of law, in explaining the role of law in shaping the development of the trade union movement, and in understanding the limits of law, including human rights law, when it comes to realising the emancipatory potential of trade unions in society today. It concludes with some observations about how legal and social actors might make use of their understanding of the legal form when it comes to harnessing the law as part of their political strategies.