The L1B visa can only stay for a maximum of five years. Most people on this visa go through the EB2 or EB3 route for a green card, which starts with the PERM process.
That in itself will take more than a year.
After PERM, you would still need to get the I140 approved and wait for your priority date to be current before you can file the I485. These waiting times for Indian applicants can be many years, depending on demand.
The issue is, five years may not be enough time to accomplish all of this. Even if you start the process the minute you arrive, the green card may not come before your visa expires.
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Unlike the H1B or L1A, long term immigrant intent is not expressly allowed by the L1B visa. This means your case must be handled with more delicacy, especially if your green card process is still in its early stages.
It does work out for some if the employer files the green card early. Others change over to an H1B through the lottery or leave and return later when the dates are current. It is possible, but by no means guaranteed.
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For most, an L1B to green card is not impossible. However, it takes early action, employer sponsorship, and a bit of luck in timing.