The Chamber’s web site has a list of their members. Most are local so it’s not much that can be done with them unless you live near there. Two of their biggest sponsors appear to be Bayer and Wells Fargo Bank. Could be a good place to start - if they lose business across the country to support one group they might think twice.
“Two of their biggest sponsors appear to be Bayer and Wells Fargo Bank.”
Great place to start. Let those companies know they will be boycotted until they break all ties to Berkely.