What are the merits of filing a patent before the end of the grace period?

The one yer grace period is only allotted in connection with the filing of US patent applications after the invention has been publicly disclosed - if you do not file your US patent application within the one-year period, you will then be statutorily barred from filing a US patent application. The reason for filing as soon as possible is that the US is now, since the AIA went into effect, a first-to-file country, so whoever files a patent application first for a particular invention is automatically the senior inventor. Therefore, let's assume you publicly disclosed your invention on January 1, 2017 - the one year grace period permits you to file a patent application by January 1, 2018, and let's say that you do not file your application until November 1, 2017, still well within the one year grace period. However, since you publicly disclosed it on January 1, 2917, another party files a patent application on June 1, 2017, five months before you file your application on November 1, 2017. They are then automatically the senior party and their patent application will be prior art against your patent application and you will be denied a patent because the other party has already obtained, or is in the process of obtaining, a patent for the same invention. As noted, this is only for US patents - your public disclosure has already prevented you from obtaining any foreign patents. As for patent pending, such a notice gives the world notice that you have a patent application pending which could result in the grant of a patent - therefore, they are on notice that they may be infringing a US patent if the patent in fact issues. Once you have filed a patent application, you have the right to use "patent pending" and it is an asset because if it in fact results in a patent being granted, patent rights are property, patent rights are assets.

One other note - one of the other panel members referred to the one-year period that one has after the filing of a provisional patent application, however, I do not believe that that one-year period is ever referred to as a "grace period" - it is a mandated time frame in which you must effectively convert a provisional patent application into a non-provisional patent application or a PCT application, and unlike the first grace period discussed hereinbefore, you do not lose any rights if you wait the entire one year period. To the contrary, your rights are preserved as of the filing date of the provisional application. In addition, by filing the provisional patent application prior to any public disclosure, you can in fact pursue foreign patents through PCT.