President Obama has just signed the America Invents Act, setting in motion a long-awaited overhaul of the US patent system, aligning it more closely with patent systems throughout the rest of the industrialised world.

1. "First-to-File" system

The most significant change resulting from the implementation will be replacement of the "first-to-invent" system, which affords rights to patent an invention to the first person in time to create the invention, with a "first-to-file" system, which affords such rights to a person who is first to file a patent application and is common to all of the other industrialised countries.

2. Applicant need not be an inventor

Another significant change will be that an entity, such as a corporation, to which an inventor has assigned or has an obligation to assign rights in the invention will be allowed to apply for a US patent; to date, the US system has required that the inventor make the application and the entity be recorded as an "assignee".

3. Opposition

The overhaul will see the introduction of an expanded system for challenging US patents at the United States Patent and Trademark Office (USPTO), including a post-grant opposition procedure that can be initiated within a nine-month period following grant, which is expected to reduce litigation and litigation-related expenses.

4. Uncooperative inventors

The overhaul will, in particular circumstances, eliminate the requirement that an oath or declaration in support of a US patent application be signed by the/each inventor, and thus remove difficulties which arise when an inventor refuses to sign.

5. Increases in USPTO fees

Most patent-related fees, including application filing fees and fees associated with issuance and maintenance of patents, will be 15% higher as of 26 September 2011.  Clients with US patent applications on which action is due should, where possible, instruct us straight away to have that action taken to avoid incurring unnecessary expense as a result of the fee increases.

6. Timing

Some of the changes have immediate effect while others will take effect at various stages over the course of the next 18 months.