4 [7] Infringement proceedings were instituted against Cipla in the Cape High Court. Judgment in favour of Adcock was given on 9 February 2009 but an appeal to the full bench is pending. These proceedings for expungement were brought because the registration of the ZEMAX was only discovered after judgment was delivered in the infringement proceedings.. [8] Section 24 of the Act permits an interested party to apply for an order removing ‘an entry wrongly made in or wrongly remaining on the register’, in this case for the removal of the trade mark ZEMAX from the register of trade marks. For reasons that will become apparent, I need deal only with s 10(14), which prohibits the registration of – ‘a mark which is identical to a registered trade mark belonging to a different proprietor or so similar thereto that the use thereof in relation to goods or services in respect of which it is sought to be registered and which are the same as or similar to the goods or services in respect of which such trade mark is registered, would be likely to deceive or cause confusion, unless the proprietor of such trade mark consents to the registration of such mark.’ [9] The court below correctly accepted that the onus rested on Adcock to establish a ‘reasonable probability’ of confusion amongst a substantial number of purchasers.2 It came to the conclusion that Adcock failed to discharge this burden. It relied primarily on the 1983 judgment in Adcock-Ingram Laboratories Ltd v Lennon Ltd.3 [10] That case concerned the alleged passing off of a medicinal tablet (Stilpane) as if it was another (Stopayne). The question whether ‘the alleged similarity of the trade marks, the colour of the tablets and their formulation’ was likely to cause confusion was considered by the court with reference to the specialised market in which prescription drugs are sold. It said that the provision of a prescription drug by a medical practitioner is a ‘definitive, deliberate act’ with full knowledge of the contents 2 SmithKline Beecham Consumer Brands (Pty) Ltd (formerly known as Beecham South Africa (Pty) Ltd) v Unilever plc 1995 (2) SA 903 (A) at 910B. 3 Two separate appeals were heard together, and are reported under the names Adcock-Ingram Laboratories Ltd v SA Druggists Ltd & another; Adcock-Ingram Laboratories Ltd v Lennon Ltd 1983 (2) SA 350 (T) at 362-364; [1983] 4 All SA 68 (T) at 79-81. Only the second appeal is relevant to this case. See also Triomed (Pty) Ltd v Beecham Group plc & others 2001 (2) SA 522 (T) at 550-1.