It is not necessary, but it is necessary

The notarization of contracts and statements is mainly to notarize trademark transfer statements or transfer contracts, clarify the subject of rights transactions, and speed up the review and approval of relevant matters. Secondly, it is to notarize trademark licensing contracts, patent licensing contracts and technology transfer contracts, gradually provide legal services for intellectual property financing, and handle notarization of intellectual property (mainly trademark rights and patent rights) pledge contracts.

Because notarial deeds have an advantage in the effectiveness of evidence and can easily solve the problems of highly concealed intellectual property infringements and difficulty in providing evidence for rights holders, parties have increasingly applied for notarization agencies to preserve evidence. Practice has proved that through the collection, fixation and preservation of evidence by notary institutions, the evidence provided by intellectual property rights holders will be more true, accurate, comprehensive and sufficient, which is conducive to parties safeguarding their legitimate rights and interests in dispute resolution, and is also conducive to the people's court's fair and efficient process. Hear cases involving intellectual property civil disputes.

Reference materials: http://www.chinacourt.org/article/detail/2015/05/id/1635377.shtml