Under what condition can post-grant review proceedings be requested?

Post-grant review (PGR) proceedings can only be requested within a specific time frame and under certain conditions, which is what makes the correct answer valid. For patents with an effective filing date on or after March 16, 2013, a PGR can be initiated within nine months from the grant of the patent. This is a key feature of the America Invents Act (AIA), which established post-grant review as a mechanism for challenging the validity of newly issued patents on a broader range of grounds than available in other proceedings, like inter partes reviews.

The significance of the nine-month limit is that it creates a window for parties who believe a patent should not have been granted, allowing them to challenge it early in its life, before potentially extensive investments are made based on the patent. This reflects the policy intention to ensure that only valid patents can be enforced, thereby fostering innovation and competition.

By contrast, the other choices reflect conditions that are either too broad or incorrect based on the regulations surrounding PGR. For example, an application filed after January 1, 2015 does not in itself qualify for a post-grant review; the critical date is the effective filing date and whether the review is initiated within the specified time frame