Question: Many big businesses are feeling insecure when brand names and project images are used by startups blatantly, confusing customers. From a legal point of view, what is the use of unauthorized images?

Answer: 
Follow to Article 129 Law On Intellectual Property 2005
Article 129. Acts of infringement of rights to marks, trade names and geographical indications
1. The following acts, if performed without the permission of mark owners, shall be deemed to be infringements of the right to a mark:
 (a) Using signs identical with protected marks for goods or services identical with goods or services on the list registered together with such mark;
 (b) Using signs identical with protected marks for goods or services similar or related to those goods or services on the list registered together with such mark, if such use is likely to cause confusion as to the origin of the goods or services;
 (c) Using signs similar to protected marks for goods or services identical with, similar to or related to goods or services on the list registered together with such mark, if such use is likely to cause confusion as to the origin of the goods or services;
 (d) Using signs identical with, or similar to, well known marks, or signs in the form of translations or transcriptions of well known marks for any goods or services, including those not identical with, dissimilar or unrelated to goods or services on the lists of those bearing well known marks, if such use is likely to cause confusion as to the origin of the goods or services or misleading impressions as to the relationship between users of such signs and well known mark owners.
2. All acts of using commercial indications identical with, or similar to, trade names of others which were used earlier for the same or similar type of goods or services, which cause confusion as to business entities, establishments or activities under such trade names shall be deemed to be infringements of the right to the trade name.
3. The following acts shall be deemed to be infringements of the right to protected geographical indications:
 (a) Using protected geographical indications for products which do not satisfy the criteria of peculiar characteristics and quality of products bearing geographical indications, although such products originate from geographical areas bearing such geographical indication;
 (b) Using protected geographical indications for products similar to products bearing geographical indications for the purpose of taking advantage of their reputation and popularity;
(c) Using any sign identical with, or similar to, a protected geographical indication for products not originating from geographical areas bearing such geographical indication, and therefore misleading consumers into believing such products originate from such geographical areas;
 (d) Using protected geographical indications of wines or spirits for wines or spirits not originating from geographical areas bearing such geographical indication, even where the true origin of goods is indicated or geographical indications are used in the form of translations or transcriptions, or accompanied by such words as "category," "model," "type," "imitation" or the like.
For all trademarks must be established on the basis of the decision of granting the protection title of the competent state agency according to the registration procedures prescribed in the Intellectual Property Law or the international registration Under the provisions of international treaties to which the Socialist Republic of Vietnam is a member , it shall not be regarded as an infringement of the right to trademark under the provisions of the treaty.
In order to avoid infringement of trademark rights, the search for marks is the first thing to do before registering for trademark protection.