Found an on-line Science (AAAS) article regarding the "March for Science" that has the following note regarding ACS under the "Say they are thinking about it. but no decision yet" heading:
"The American Chemical Society (ACS) in Washington, D.C. “The American Chemical Society is impressed with [the] number of individuals who have already voiced their support for science and the march—it is a testament to the grassroots organizing power of social media. ACS is currently seeking to gain greater insight into the goals and messaging of the march to determine if there is an appropriate role for the Society,” reads a statement from ACS (more than 157,000 members)."
I spoke to an individual yesterday who is helping an Albuquerque, New Mexico "March for Science". In presenting question of participation / support to our Central New Mexico Local Section was wanting to also provide information on the ACS endorsement or not for participation. Not sure if the statement above from Science is still the ACS viewpoint and if that viewpoint may change any time soon?