The principles
112In Cactus Imaging Pty Ltd v Peters [2006] NSWSC 717; (2007) 71 NSWLR 9, Brereton J summarised the relevant principles:
"10 Although at common law a restraint of trade is contrary to public policy and void unless it is justified by the special circumstances of the particular case (for which purpose it is sufficient justification that the restriction is reasonable having regard to the interests of the parties concerned and in reference to the interests of the public, so that while affording adequate protection to the party in whose favour it is imposed, it is not injurious to the public) [Nordenfelt v Maxim Nordenfelt Guns & Ammunition [1894] AC 535, 565; Herbert Morris Ltd v Saxelby [1916] 1 AC 688, 706, 707; Lindner v Murdock's Garage (1950) 83 CLR 628, 653], in New South Wales a restraint is valid to the extent to which it is not against public policy, even if not in severable terms [Restraints of Trade Act, 1976 (NSW) s 4(1); Koops Martin Financial Services Pty Ltd v Reeves [2006] NSWSC 449, [26]-[27]]. The effect of the Restraints of Trade Act is that, in New South Wales, one approaches this type of case by determining, first, whether the alleged breach (independently of public policy considerations) does or will infringe the terms of the restraint properly construed; secondly, whether the restraint in its application to that breach is against public policy; and thirdly, if it is not, then in its application to the alleged infringing conduct, the restraint is valid unless the court makes an order under Restraints of Trade Act, s 4(3) [Orton v Melman [1981] 1 NSWLR 583; Woolworths Limited v Olson [2004] NSWCA 372, [42]]. That is because the effect of the Restraints of Trade Act, s 4(1), is to require that, for the purpose of determining the validity of a restraint, attention be focussed on the actual or apprehended breach, rather than on imaginary or potential breaches.
11 While the same general principle applies in all cases of restraint of trade, a stricter and less favourable view is taken in respect of covenants in restraint of trade between employer and employee than in commercial agreements for sale of goodwill [Nordenfelt, 566; Mason v Provident Clothing & Supply Co Limited [1913] AC 724, 731, 738; Herbert Morris Ltd v Saxelby; Geraghty v Minter (1979) 142 CLR 177, 185; Woolworths Limited v Olson, [38]; J D Heydon, The Restraint of Trade Doctrine, 2nd Ed, pp68-69]. An employer is not entitled to be protected against mere competition, and the legitimate interests of an employer which may be the subject of protection by covenant are in the nature of proprietary interests [Vandervell Products Ltd v McLeod [1956] RPC 185, 192; Tank Lining Corp v Dunlop Industrial Pty Ltd (1982) 140 DLR (3d) 659, 664], including the employer's trade secrets and confidential information, and the employer's goodwill including customer connection. In this case, Cactus seeks to support the restraint on solicitation of customers on the basis of protection of both its confidential information and its customer connection.
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25 It is plain that an employer's customer connection is an interest which can support a reasonable restraint of trade [Hitchcock v Coker (1837) 6 Ad & El 438, 454; [1835-42] All ER Rep 452, 456-7 (Tindal CJ); Herbert Morris Ltd v Saxelby, 709; Dewes v Fitch [1920] 2 Ch 159, 181; Coote v Sproule (1929) 29 SR (NSW) 578, 580 (Harvey CJ in Eq); Lindner v Murdock's Garage, 633-634 (Latham CJ, Webb J agreeing), 650 (Fullagar J), 654 (Kitto J); Koops Martin v Reeves, [29]-[33]]. Such a restraint is legitimate if the employee has become, vis-à-vis the client, the "human face" of the business, namely the person who represents the business to the customer - or, as it was put by Hoover J in Arthur Murray Dance Studios of Cleveland Inc v Witter 105 NE (2d) 685, 706 (Ohio, 1951): "The personal relation between the employee and the customer [is] such as to enable the employee to control the customer's business" [Twenty-First Australia Inc v Shade (NSWSC, Young J, 31 July 1998, unreported), BC9803667, 12; Koops Martin v Reeves, [34]]. While the employer is not entitled to be protected against mere competition by a former employee, the employer is entitled to be protected against unfair competition based on the use by the employee after termination of employment of the customer connection which the employee has built up during the employment - which, because the employee has in effect represented the employer from the customer's perspective during the employment, might at least temporarily appear attached to the employee, but in truth belongs to the employer [Koops Martin v Reeves, [30]].
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37 The reasonableness of a restraint must be judged at the time when the contract was made ...
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41 As White J has said in Aussie Home Loans v X Inc Services (2005) ATPR par 42-060, the reasonableness of the duration of an otherwise justifiable restraint is often difficult to gauge, and where the parties have equal bargaining power it will often be appropriate to regard them as the best judges of what length of period is reasonable - although, as the result of that case itself shows, such considerations are far from conclusive ..."
113In Jardin v Metcash Ltd [2011] NSWCA 409; (2011) 285 ALR 677, Meagher JA (Campbell and Young JJA agreeing) said:
"95 Expressions which describe the necessary relationship as one in which the employee is the "human face" of the employer do so to emphasise that the source of the influence must be the personal relationship which is likely to develop, or has developed, between the employee and customer as a result of dealings between them on behalf of the employer and its business. In Stenhouse Australia Ltd v Phillips [1973] 2 NSWLR 691; [1974] AC 391 at 400 the Privy Council emphasised the distinction between the use of the employee's personal skill or experience, against which the employer is not entitled to be protected, and the use of some advantage or asset inherent in the business which can properly be regarded as the employer's property which might legitimately be protected from appropriation by an employee for his or her own purposes. In Miles v Genesys Wealth Advisers Ltd, this Court adopted that statement of principle and described the relationship between a senior employee and customers with whom that employee had fostered close and productive relationships as being "to a substantial extent" the property of his employer notwithstanding that the relationship had also developed and been supported at least in part by the employee's own qualities of skill and experience: at [38], [41], [54], [55].
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97 These statements are not, however, to be understood as requiring that the employee be proved to be in a position to control whether the customer remain with or leave the business. The employer is entitled to protection against the use of "personal knowledge of and influence over" its customers, which the employee might acquire in the course of his or her employment, so as to undermine its customer connections: Herbert Morris Ltd v Saxelby [1916] 1 AC 688 at 709; Lindner v Murdock's Garage (1950) 83 CLR 628 at 635, 636, 645, 647, 654. It is against the "possibility" of its business connection being adversely affected by the use of that "personal knowledge and influence" that the employer is entitled to be protected: Lindner v Murdock's Garage at 636, 645, 654. Latham CJ (dissenting) summarised the relevant principle as follows (at 636):
'Where an employee is in a position which brings him into close and personal contact with the customers of a business in such a way that he may establish personal relations with them of such a character that if he leaves his employment he may be able to take away from his former employer some of his customers and thereby substantially affect the proprietary interest of that employer in the goodwill of his business, a covenant preventing him from accepting employment in a position in which he would be able to use to his own advantage and to the disadvantage of his former employer the knowledge of and intimacy with the customers which he obtained in the course of his employment should, in the absence of some other element which makes it invalid, be held to be valid.'"
114In Koops Martin v Dean Reeves [2006] NSWSC 449, Brereton J said:
"30 While the employer is not entitled to be protected against mere competition by a former employee, the employer is entitled to be protected against unfair competition based on the use by the employee after termination of employment of the customer connection which the employee has built up during the employment - which, because the employee has in effect represented the employer from the customer's perspective during the employment, might at least temporarily appear attached to the employee, but in truth belongs to the employer. The employer is entitled to be safeguarded against use after termination by the employer of special knowledge of or influence over customers gained as a result of customer contact during the employment. Thus in Herbert Morris v Saxelby, Lord Parker (at 709) said that a covenant was upheld to protect an employer from, amongst other things, a former employee's influence over customers. In Dewes v Fitch [1920] 2 Ch 159, Warrington LJ said (at 181) that an employer was entitled to protection against the influence acquired by the employee over the customers or clients. In Coote v Sproule (1929) 29 SR (NSW) 578, Harvey CJ in Eq said that what was entitled to protection was customer connection through a special relationship between employee and customer as a consequence of the employment (at 580):
'An employer is entitled to hold his employee to an agreement not to injure the former's business connection by virtue of the special relationship which has existed between the employee and the employer's customers as a consequence of his employment.'
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44 A more robust view is taken where the employee's role includes obtaining and extending custom for the employer's business. When an employee's duty includes to build up the employer's clientele as well as to deal with existing clients, a wide restraint is more likely to be upheld, because in such circumstances the employer is entitled to protection against the employee taking advantage of the period of service to prepare for later competition [G W Plowman & Sons Limited v Ash [1964] 1 WLR 568; [1964] 2 All ER 10; Normalec Limited v Britton [1983] 9 FSR 318, 324; Dean, The Law of Trade Secrets, 2nd edn, [11.150]. In such a case, the establishment of a customer connection is not merely incidental to the employment, but its purpose. In that context, a covenant is considered reasonable, first, to remove the temptation that by cultivation of the target market during employment, the employee may prepare the ground for its exploitation by himself after the employment ends, rather than for his employer during the employment; and, secondly, to prevent exploitation after termination of the employment by the employee of a connection with the customer which the employer has paid the employee to establish for the employer's benefit. In this context in particular, the fact that in pursuance of his or her obligations under the employment contract an employee has for reward introduced customers who include relatives, friends and acquaintances does not [absent specific agreement to the contrary: see Sharah v Healey [1982] 2 NSWLR 223] remove or cut away the basis which would otherwise exist for a restraint."