Intangibles constitute nowadays the most precious value for companies worldwide, enabling them to be settled as intellectual property rights or as trade secrets, on which this article focuses. On the one hand, this article takes a broad legal approach to their presence in the Spanish legal system, showing that they provide two types of protection: a civil protection, through the Unfair Competition Law, and a criminal protection, through the Criminal Code, which includes criminal responsibility for legal persons. Each of these two types of protection has particular features, but they are almost identical, as they punish, although with different legal consequences, the same actions against trade secrets. On the other hand, the purpose of this paper is also to explore the connection between trade secrets and intellectual property rights, specifically patent rights. Both kinds of intangibles share many aspects and the international legal instruments confirm it, but their main difference is the instrument of protection: while intellectual property rights receive protection through their registration, trade secrets have to be safeguarded through specific measures adopted by their holder in order to keep their confidentiality. From this difference others are derived, but, despite their existence, they work as supplementary systems.