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Background: Allergic contact dermatitis to isobornyl acrylate has been reported in only two cases in literature. Therefore, isobornyl acrylate is not part of a (meth) acrylates patch test series. At our department an industrial worker presented with therapy-resistant hand eczema and sensitizations for various non-relevant acrylates. After scrupulous examination of his work area and an expanded patch test series, isobornyl acrylate 0.1% turned out to be the unexpected allergen. Objectives: (i) To investigate whether it is relevant to add isobornyl acrylate to the (meth) acrylate test series at our department. (ii) To determine the correct patch test concentration. (iii) To study whether there could be cross-reactivity with other acrylates. Methods: Patients with a proven acrylate sensitization, diagnosed between 1-1-2000 and 1-1-2012, were selected from the database of our department. Included subjects were patch tested with a dilution series of isobornyl acrylate (0.3%, 0.1%, 0.033% and 0.01% in petrolatum). Readings were performed on D2, D3 and D7 and graded according the ICDRG guidelines. Results: Twelve subjects were patch tested with the isobornyl acrylate dilution series. None of them showed signs of sensitization. Three subjects (25%) showed an irritant reaction on D3 to the isobornyl acrylate 0.3% dilution. Conclusion: We showed an additional rare case of allergic contact dermatitis to isobornyl acrylate. Cross-reactivity with other acrylates could not be demonstrated in this small group of patients. This study provides insufficient support for isobornyl acrylate to be added to a (meth) acrylates patch test series. The ideal patch test concentration seems to be 0.1%