In the light of growing global mobility, complexity, and information exchange, multilingualism has emerged as an important contributor to knowledge-based economies and societies (Europublic, 2009). Yet from a psycholinguistic perspective, we understand very little about how multiple languages are stored and processed in the memory of a language user. Therefore, the major aim of this study is to shed more light on the multilingual lexico-semantic representation, based on data from a primed lexical decision task (LDT) with German speakers of English (L2) and French (L3). This is done to address the question of automatic activation of lexico-semantic links between multiple languages. The results revealed priming effects from L1 to L2, L3 to L2, and L3 to L1. Also, priming asymmetry effects were noted between all language pairs. The results are discussed with reference to other experimental paradigms employed by previous multilingual studies in order to account for variability of the multilingual mental lexicon findings and, in turn, to evaluate the Modified Trilingual Lexical Memory model (Tytus, 2017).