Ann: Upcoming Investor Video Presentation, page-16

I wasn't familiar with Tata v HUL, (truth is I've never read an Indian court decision - the basis of Indian patent law is (mostly pre-EU) English patent law, as it is in Australia) so I read a summary:

https://spicyip.com/2012/07/tata-chemicals-wins-patent-revocation.html
a 2012 decision of the Indian IP Appellate Board. The link in this article to the court decision does not work, but I found the court report at:
http://www.dpahuja.com/Patent/166-Tata%20Chemicals%20Limited%20v%20Hindustan%20Unilever%20Ltd.pdf .

I don't know if this has been considered by a higher court in India.
The patent (IN 195937 for an upwardly mobile water filter) was revoked on the ground of obviousness and lack of novelty in the light of two US patents US6387260 and US3909402.

HUL were also criticized for not informing the Indian Patent Office of other prior art found during the corresponding International Search of the PCT application, even though the most relevant prior art document was independently cited by the Indian patent examiner. This is discussed from para 73 onwards.

This case considered statute law, the Indian patents act. I don't think natural justice or amendment were considered.

In Australia, ownership of a patent derives from the inventor and any contractual or other obligations binding the inventor.