Here's what you need to know about the case:
The Supreme Court will decide whether Mr Shinde and 15 other MLAs should be disqualified for revolting against then Chief Minister Uddhav Thackeray in June last year.
Mr Thackeray had asked the top court to step in after Mr Shinde, backed by the opposition BJP, split the Shiv Sena and led most of the MLAs to form a new government.
If Mr Shinde is disqualified, he will have to resign as Maharashtra Chief Minister and his government will be disbanded.
Whichever side has greater numbers - a volatile equation depending on whether any MLAs from either side change sides - will then stake claim to a new government.
The decision depends on a five-judge bench of the Supreme Court led by Chief Justice DY Chandrachud who have clustered eight petitions on the face-off.
Senior lawyers Kapil Sibal and Abhishek Manu Singhvi argued for Uddhav Thackeray's team in the court while Harish Salve, Neeraj Kaul, and Mahesh Jethmalani represented Eknath Shinde's camp.
A day before the verdict, Maharashtra BJP chief Chandrashekhar Bawankule claimed the ruling Shiv Sena-BJP alliance has 184-plus votes in the 288-member assembly and can prove its majority if needed.
Arvind Sawant, an MP from Uddhav Thackeray's Shiv Sena, said, "This is a fight to save the constitution and democracy. The law is with us."
Before the hearings in the case ended in March, the court had asked Mr Singhvi to explain how Mr Thackeray's government could be restored when he had resigned as Chief Minister instead of facing a vote in the assembly.
Ruling on the tussle in February, the Election Commission had allotted the Shiv Sena party name and its bow-and-arrow symbol to Mr Shinde. Mr Thackeray's smaller faction was given the name Shiv Sena Uddhav Balasaheb Thackeray and the symbol of a flaming torch.
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