Quaid-e-Azam

Muhammad Ali Jinnah, as we know him to be, was always well-regarded as a very clever man, as most of his contemporaries admitted in his time. By altering his name from “Jinnahbhai” to “Jinnah”, as well as his date of birth, he created a complete legal disconnect from the affairs of the Mahomedalli Jinnahbhai corporation which was setup by his father. His siblings were also most likely its shareholders, which may be why they call came to be known with a surname of “Jinnah” later on.
Company law does require personal details of its directors and majority shareholders, such as the full ‘legal name’ and date of birth. With this information altered, there would virtually be no legal connection between an individual and the corporation.
The even bigger kicker is… by reducing his age by 1 year and 66 days, Muhammad Ali Jinnah would ‘officially’ have been 19 years of age upon his return to India when he had to face this mess. This means that even if people were litigating a business setup under his former name, it would be legally impossible because in those years the legal age to be an adult was 21, and he would therefore be considered to be a minor! Interestingly enough, this is precisely the argument which Jinnah used in his much later years when defending Ilm Din during a popular murder trial in Lahore.