Resumen: In this paper we show the unexpected property that extension from local to global without loss of regularity holds for the solutions of a wide class of vector-valued differential equations, in particular for the class of fractional abstract Cauchy problems in the subdiffusive case. The main technique is the use of the algebraic structure of these solutions, which are defined by new versions of functional equations defining solution families of bounded operators. The convolution product and the double Laplace transform for functions of two variables are useful tools which we apply also to extend these solutions. Finally we illustrate our results with different concrete examples. Idioma: Inglés DOI: 10.1215/17358787-3345137 Año: 2016 Publicado en: BANACH JOURNAL OF MATHEMATICAL ANALYSIS 10, 1 (2016), 196-208 ISSN: 1735-8787 Originalmente disponible en: Texto completo de la revista