What effect did the open door policy have on the spread of imperialism?

The effect that the Open Door Policy did on the spread of Imperialism is that, this stopped the nations from putting up colonies in the country of China. The Open Door Policy is actually a policy or proposal made by the United States and China. The aim of this policy is to protect the equal privileges for those countries who are trading with China. Way back then, China was a weak country and this open door policy has prevented other nations to take advantage of this.