In Robins v. Pruneyard Shopping Center (1979) 23 Cal. 3d 899 153 Cal. Rptr. 854, 592 P.2d 341, the California Supreme Court was concerned about the fact that central business districts connected by public thoroughfares and sidewalks on which citizens could congregate and express themselves were increasingly "yielding their functions" to privately owned suburban shopping centers. ( Pruneyard, supra, 23 Cal. 3d at p. 907.) These shopping centers were in many ways, the functional equivalent of downtown business areas but were entirely contained on private property. The particular shopping center at issue in Pruneyard was approximately 21 acres--"5 devoted to parking and 16 occupied by walkways, plazas, and buildings that contain 65 shops, 10 restaurants, and a cinema." ( Id. at p. 902.) Reversing a then recent contrary decision, Diamond v. Bland (1974) 11 Cal. 3d 331 113 Cal. Rptr. 468, 521 P.2d 460, the court concluded that "shopping centers to which the public is invited can provide an essential and invaluable forum for exercising speech and petition rights," and held that "sections 2 and 3 of article I of the California Constitution protect speech and petitioning, reasonably exercised, in shopping centers even when the centers are privately owned. " ( Pruneyard, supra, at p. 910.) The court recognized in Pruneyard that the needs of the public to free expression in quasi-public areas such as shopping centers must be balanced by the private property interests of the owners. The majority in Pruneyard quoted with approval a statement made by dissenting Justice Mosk in Diamond v. Bland, supra, 11 Cal. 3d 331: " 'It bears repeated emphasis that we do not have under consideration the property or privacy rights of an individual homeowner or the proprietor of a modest retail establishment. As a result of advertising and the lure of a congenial environment, 25,000 persons are induced to congregate daily to take advantage of the numerous amenities offered by the shopping center there. A handful of additional orderly persons soliciting signatures and distributing handbills in connection therewith, under reasonable regulations adopted by defendant to assure that these activities do not interfere with normal business operations citation would not markedly dilute defendant's property rights." ( Pruneyard, supra, 23 Cal. 3d at pp. 910-911, quoting Diamond v. Bland, supra, 11 Cal. 3d at p. 345 (dis. opn. of Mosk, J.).) The court in Pruneyard also cited Justice Traynor's opinion in In re Hoffman (1967) 67 Cal. 2d 845, 852-853 64 Cal. Rptr. 97, 434 P.2d 353, for the proposition that "property owners as well as government may regulate speech as to time, place, and manner." ( Pruneyard, supra, at p. 909.)