Yes. They will check with companies whose experience certificate you provide firstly to see if the certificates are valid or not, and then to see whether you are actually working with them or if these certifications are printed, etc.

Your last employer is most crucial. For example, if Microsoft is your last job, you will automatically present the reliving letter from Microsoft, so they will ask for more detailed information about you, such as your conduct, or they will sometimes ask for BGV done by Microsoft.

Generally, the aim of BGV is to ensure that everything you give, such as certificates and marksheets, is validated.