For starters, the case confirms that there is no "image right" or "character right" in English law which allows a celebrity to control the use of his or her name or image. Rihanna's claim was brought under the law of passing off, which required her to prove she had a reputation and goodwill in connection with her business activities and that the use of her image on the t-shirt amounted to a misrepresentation which was likely to deceive members of the public into believing it was approved of and authorised by her.
Furthermore, the decision in Rihanna's favour was described by one of the judges as "close to the borderline". Her victory hinged on two specific facts of the case: the fact that there had been some association between Rihanna and Topshop in the past (a publicised shopping trip by the singer to the Oxford Street flagship store, and a competition by the retailer offering the prize of a personal shopping appointment with her); and the fact that the image on the offending t-shirt very closely resembled authorised promotional material for the Talk that Talk album.
So Rihanna has not established (and to be fair did not claim) any wide-ranging image right that would prohibit the world at large from selling t-shirts or other merchandise bearing her image without her approval. Yes, she has obtained an injunction prohibiting Topshop from continuing to sell the offending t-shirt without making it clear that it is not authorised or approved by her. But in the absence of any freestanding image right it is unclear what value this is likely to be to Rihanna, when other retailers will be able to sell different t-shirts with different Rihanna prints without it amounting to passing off. And any damages awarded on sales to date of Topshop's t-shirt are unlikely to justify the costs of going to Court: on reported sales figures of some £250,000, they may amount to at best £25,000.
And what about Topshop? They have lost a case which, presumably, they could have settled more amicably at an earlier stage, and now, you would imagine, there is little chance of them being able to sell authorised Rihanna merchandise or run Rihanna promotions, or indeed of Rihanna going shopping in one of their stores.
So who is the real winner?