The client explains the cause of action, the reasons for invalidation and the factual basis, and determines the purpose of the request for invalidation. Sign an invalidation agency contract and a patent agency power of attorney. The client shall submit proof of identity, including a copy of the business license and the identity certificate of the legal representative; if the client is an individual, a copy of the identity card shall be provided. The client shall pay relevant expenses in advance, including agency fees, invalidation request fees, evidence collection and investigation fees, search fees, travel expenses and other actual related expenses. The client provides in writing relevant search information involving prior rights related to the invalid patent, or provides relevant technical information in the same technical field, similar technical field, or related technical field. The information provided by the client should be the original. If only a copy is provided, a written certificate should be provided at the same time, including the source, printing, publication time of the copy and the cover, second cover, third cover or back cover, title page, etc. If it involves the invalidation of a design patent, you must also provide various materials that are the same as or similar to the patent, such as photos, albums, etc., and provide as much as possible invoices, contracts, physical products and other notarized prior manufacturing and sales materials. Public evidence.