Duration of Stay on Visitor Visa

[keshavs]

Hi,

My parents have a 10 year multiple entry Visitor Visa. I am planning to Bring them here in May 2007. If they stay here for 6 months and go back in Nov 2007, when can they visit USA again? If they stay in India for 5-6 months, can they travel agin in April/May 2008?

Thanks

[peace]

The general idea is to stay more in India than in US in any 12 month period.
If they spend 6 months in US, they should live 6-7 months in India before returning.