diff --git a/graphiti-openapi.gemspec b/graphiti-openapi.gemspec
index 55e392f..1e2ebd3 100644
--- a/graphiti-openapi.gemspec
+++ b/graphiti-openapi.gemspec
@@ -25,7 +25,7 @@ Gem::Specification.new do |spec|
   spec.executables = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_runtime_dependency "activemodel", "~> 6.0"
+  spec.add_runtime_dependency "activemodel"
   spec.add_runtime_dependency "graphiti", "~> 1.3.9"
   spec.add_runtime_dependency "dry-struct", "~> 1.0"
   spec.add_runtime_dependency "transproc"