Dear friend,
The suffix behind the name of any business venture such as "Pvt Ltd", "Public Ltd" etc., denotes the constitution/type of the organization as incorporated under the Companies Act, 1956. As such, it has an existence as a separate legal entity distinct from its investors. Therefore, it is a juristic person or artificial person in the eyes of the law subject to all legal rights and liabilities.
To me, your word "Labour Licence" is a bit vague. A license is a broader term indicating a permit issued by a Statutory Authority to own or use something, to do something, or to carry on a trade. Employment or labor in any activity, in general, would be called as such when people are hired for wages or reward or compensation in consideration of the services rendered by them. So, the question of licensing in respect of the employment of labor is dependent on factors like the nature of the activity carried on, the type of the establishment, the number of people employed, the duration of employment. For example, the contract labor system prevalent in all industrial establishments, Employment of interstate migrant workmen in industrial establishments, the building and other construction activities, factories, motor transport undertakings, shops, and other establishments, etc.
The terms "workman", "worker", "employee" are used in Labor Laws depending on their respective purposes for the generic term "labor", if I am correct. However, my suggestion to you to appreciate and understand the inherent differences between such terms would be referring to the concerned definition clauses of the terms used as such in the Employees Compensation Act, 1923, The Industrial Employment (Standing Orders) Act, 1946, The Industrial Disputes Act, 1947, The Factories Act, 1948, The EPF Act, 1952, The Payment of Bonus Act, 1965, The Payment of Gratuity Act, 1972, various States Shops and Establishments Acts.