During the process of closing a registration for a client in the state of Washington I found the attached document dor.wa.gov/Docs/Pubs/SpecialNotices/2010/SN_10_TrailingNexus.pdf that outlines the states view on companies that wish to close their account.
This is one of the few published policies on the “trailing nexus” theory that I’ve mentioned before. Under this policy, the state of Washington requires out of state retailers who stop having nexus with the state must continue to file returns for 4 years under this trailing nexus theory. This theory holds that the nexus created by your business has a lingering affect in terms of generating sales and creating revenue for your company. As such, the state of Washington wants sales tax to be collected on any taxable transaction even though you don’t have direct nexus.
Many states take this position but this is one of the few I have seen that actually has a published policy on the matter.