Interim Injunctions In Jersey: American Cyanamid Plus

• Published date: 11 November 2025
• Law Firm: Walkers
• Author: Simon Hurry and Daniel Read

Key Takeaways

• The American Cyanamid test remains the standard test in Jersey for interim injunctions.
  
  
• However, a more exacting 'Cyanamid Plus' test may be applied in exceptional cases, particularly where the interim relief would effectively grant the final remedy or render a trial otiose or where both sides risk comparable, hard to quantify harm.
  
  
• Practical case management can be decisive, especially for time sensitive disputes such as those concerning restrictive covenants where expedited proceedings may avoid the need to modify the standard test.

Interim injunctions are intended to protect a party against loss or damage arising from a violation of their rights for which they cannot be adequately compensated in damages if they ultimately succeed at trial.

In Jersey, the primary test for obtaining an interim injunction (which is different to a freezing injunction¹) was established by the House of Lords in American Cyanamid Co v Ethicon Limited [1975] AC 396 (Cyanamid Test).

The Cyanamid Test has been applied by the Royal Court of Jersey (Court) regularly. The plaintiff is required to sufficiently evidence the following:

• there is a serious question to be tried;
  
  
• damages awarded at trial would be an inadequate remedy for the plaintiff;
  
  
• damages would be an adequate remedy for the defendant if an injunction were granted to the plaintiff to which they were later found not to be entitled; and
  
  
• if damages would not be an adequate remedy...