Is there a mechanism for the public to participate on the examination process of a patent under examination? More specifically, is there a mechanism, for a person or for a company, to submit objection to a patent under examination by the USPTO once the patent is published and is considered to be not new or not obvious by the third party (person or company)?
As revised by the America Invents Act (AIA), 35 U.S.C. § 122(e) expands the opportunity for third-party pre-issuance submissions in US patent cases. Anyone is permitted to submit published documents ('printed publications') that are relevant to the examination of a pending application along with a concise explanation of the importance of the documents submitted.
The AIA provides the general standards for preissuance submissions of patents, published patent applications, or other printed publications in patent applications.
Preissuance submissions may be filed by any member of the public, including private persons and corporate entities such as AskPatents. The only limitation is that the third party may not be the applicant or any individual who has a duty to disclose information with respect to the application under 37 C.F.R. § 1.56.
If the Examiner raises a rejection in view of the submitted document, only the applicant, not the third party, can respond.
The good news is that AskPatents was created specifically to facilitate the submission of pre-issuance submissions to the USPTO. Any interested user on AskPatents can create a prior-art-request on a US Patent Application. Other users submit proposed prior art. After a suitable period to solicit exemplary prior art, the best prior art is vetted by volunteer lawyers and submitted to the USPTO by the AskPatents community.
There is a new, but very limited way, for 3rd parties to participate. In fact this site, Ask Patents, was created as a way leverage "the crowd" to use this new feature of the AIA changes to patent law. Third parties can only participate by submitting prior art documents and brief explanations of their relevance during a particular time window. Please see the much more complete answer by Micah.