The invention relates to copolymers based on phosphorous-containing monomers (A) and on macromonomers (B), to methods for the production thereof and to their use as additives for inorganic binding agent suspensions based on cement, lime, gypsum and anhydrite. The corresponding polymeric additives have, as flow agents, excellent water-reducing properties and hold the flowability of the concrete over a relatively long period of time (60 to 90 min.) to an almost unchanged level without having delayed action. In addition, the corresponding polymeric additives improve the processing and setting processes of the building materials produced with these additives by making possible earlier and higher resistances to pressure.