Indian patent journal of this week (Sep 16th, 2011) has a post grant opposition filed under section 25(2).
Lupin has filed post grant opposition to 240930 (2210/Cal/1998) under section 25(2) on June 08, 2011. The ‘930 patent seems to cover Fosamprenavir, is assigned to Vertex Pharma and titled “Prodrugs of aspartyl protease inhibitors“. The ‘930 patent is equivalent to US patent 6,436,989 and expires on Dec 2018 in india. The same patent is opposed by Ranbaxy too. Ranbaxy filed opposition on Sep 2010. Notice of opposition (Form 7) filed by Ranbaxy is available on iPAIRS site.
Fosamprenavir is phosphoric acid derivative of amprenavir (prodrug), approved in USA.