There is included a method and apparatus comprising computer code configured to cause a processor or processors to perform obtaining video data, obtaining a coding unit (CU) block, determining whether a flag of the CU block is set to a predetermined flag condition, determining whether a tree type of the CU block is set to a predetermined tree type, determining whether to signal an adaptive color transform (ACT) flag based on any of whether the flag of the CU block is set to the predetermined flag condition and whether the tree type of the CU block is set to the predetermined tree type, and coding the video data based on a whether the ACT flag is signaled.