This paper will talk about the not-so-new trend in the field of publishing. Namely, globalization in the broadest sense, and then, consequently, the globalization of publishing is a phenomenon that leads to the fact that books published in a certain country are very often found in other countries as well. Conglomeration of publishing is a phenomenon that forms large transnational conglomerates from small independent businesses by merging them. A perfect example of this are precisely the British and American market, given the fact that English is the lingua franca in today's age. From various companies dealing with information and communication technology, through multimedia companies, to transnational conglomerates, the buyers of publishing companies do not see publishing as their core activity, but as one of many, which in the context of the book market and the cultural sphere is not an ephemeral fact. This brings us to the question of enormous structural changes in the field of publishing. The aim of this paper is to show the changes that the publishing industry is going through in the mentioned process, as well as the positive and negative sides of the new way of doing business and acting. In addition, the aim is to describe how this changes the cultural industry of the book, and consequently leads to the commercialization of the book as an artistic and cultural asset. Furthermore, special emphasis will be placed on authors and their position in the new market. The aforementioned changes will be shown in the review of three large publishing conglomerates that often appear on the lists of the world's largest publishing companies - Penguin Random House, Hachette Book Group and Simon & Schuster.