The present invention relates to solid salt forms of the 3-pyrrole substituted 2-indolinone compound 5-[5-fluoro-2-oxo-1, 2-dihydro-indol-(3Z)-ylidenemethyl]-2,4-dimethyl-1H-pyrrole-3-carboxylic acid (2-pirrolidin-1-yl-ethyl)-amide. It also relates to polymorphs of the phosphate salt of the amide. The invention further relates to the use of the salts and polymorphs in the treatment of protein kinase related disorders.