be open to dispute
From Longman Dictionary of Contemporary Englishbe open to disputebe open to disputeDISAGREEif something is open to dispute, it is not completely certain and not everyone agrees about it His interpretation of the poem is open to dispute. → disputeExamples from the Corpusbe open to dispute• How far Blake and Mouton were pioneers in this field is open to dispute.• Whether this revolution has improved medical care or worsened it is open to dispute.