The hand position that the actor-and-would-be politician is known for is often likened to "apana mudra", a yoga finger and palm posture.
And now, Mumbai's Voxweb, an 18-month-old social networking app, says that it is similar to its logo.
"If another company or brand has a similar logo, it will not matter much. But social media and political parties have quite a few similar traits - they have mass adoption, they are really close to their user base and so on. This creates a conflict," Voxweb founder Yash Mishra said.
The mudra is seen by Rajinikanth's legion of followers as his trademark gesture, ever since he raised two fingers and folded two in his 2002 film 'Baba'. The actor holds the two middle fingers down with his thumb and raises the little and index fingers in a broad vee.
The symbol figured prominently on the stage at a series of meetings addressed by the mega star recently. Fans also carried placards with the hand symbol.
Voxweb, Mr Mishra said, has a similar brand logo, but with the thumb left free.
The startup has written to the actor over the issue, but is yet to hear from him. There was no response to messages sent by PTI to the star's publicity team.
Asked what measures he planned to take to save his logo from the Rajinikanth juggernaut, Mr Mishra said his moves would depend on the new political outfit's reactions.
"We are open to suggestions and would ask them to make some alterations. All that we have to say is there is absolutely no relationship between the company and the party or its ideology," he said.
Rajinikanth had said last month that he would soon launch a political party in Tamil Nadu.
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