There are two main approaches to the problem of donkey anaphora (e.g. If John owns a donkey , he beats it ). Proponents of dynamic approaches take the pronoun to be a logical variable, but they revise the semantics of quantifiers so as to allow them to bind variables that are not within their syntactic scope. Older dynamic approaches took this measure to apply solely to existential quantifiers; recent dynamic approaches have extended it to all quantifiers. By contrast, proponents of (...) E-type analyses take the pronoun to have the semantics of a definite description (with it ≈ the donkey, or the donkey that John owns ). While competing accounts make very different claims about the patterns of coindexation that are found in the syntax, these are not morphologically realized in spoken languages. But they are in sign language, namely through locus assignment and pointing. We make two main claims on the basis of ASL and LSF data. First, sign language data favor dynamic over E-type theories: in those cases in which the two approaches make conflicting predictions about possible patterns of coindexation, dynamic analyses are at an advantage. Second, among dynamic theories, sign language data favor recent ones because the very same formal mechanism is used irrespective of the indefinite or non-indefinite nature of the antecedent. Going beyond this debate, we argue that dynamic theories should allow pronouns to be bound across negative expressions, as long as the pronoun is presupposed to have a non-empty denotation. Finally, an appendix displays and explains subtle differences between overt sign language pronouns and all other pronouns in examples involving ‘disjunctive antecedents’, and suggests that counterparts of sign language loci might be found in spoken language. (shrink)