Novelty
Critical date Patent owner’s date of invention
Difficult to prove
RTP or patent filing date if no other proof
§102(a)
Depends on other people
Prior art must have been
Known by others in this country; or
Fully disclosed
RTP date before critical date
Actual RTP = creating prototype
Construct RTP = filing a patent in the US
Or creating a writing that describes patent in sufficient detail
Available to public
Private or secret knowledge of the invention is not enough
Private companies, secret reports, and abandoned patent applications are not available to the public
Even oral description to third parties who can disseminate the information to others can be available to public
Other countries does not help; only in the US
Used by others in this country; or
IF reduced to actual practice and used in the manner in and for the purpose which it was intended, AND
Publicly accessible
This does not mean it has to be explained to the public though
Nor does it need to be enabling
Printed publication in this or another country; or
Printed
Interpreted broadly
Audio, video may count as printed
Tangible, permanent form that was discernible to public
Public
Accessible
If Americans, exercising due diligence, could have found it
IS
Thesis found in public library and indexed correctly
Limited number of documents given out to members of a conference as long as no secrecy requirement
IS NOT
Thesis found in public library but not indexed correctly
Thesis in private library
Enabling
Enables a person of ordinary skill in the art to make it without undue experimentation
Patented in this or in a foreign country
Generally, patents are published and so serve as a printed publication
Some countries do not publish patents or do not publish until a bit after the patent has been issued
Applicant’s invention patented
Was it the applicant’s invention?
Only those claims which were granted to the foreign patent
Even if the patent were fully disclosed in the foreign patent, if it was not claimed, not patented
Date of patenting
Date the protections were granted
§102(e)
Bars patent if at the time of invention, the invention was in a patent application pending in the PTO and the application was either published or granted
§102(g)
Bars patent if was invented by another inventor before invention date and the other inventor did not abandon, suppress, or conceal the invention
Who invented first?
Presumption that the first to reduce to practice is the first to invent but rebuttable
RTP date; OR
Conception date AND
Has the full idea of the invention
Due diligence in reducing to practice AND
Gaps in effort only excusable if reasonable (poverty, illness)
RTP after second inventor
So 
First to conceive + first to RTP = first to invent
First to conceive + due diligence + second to RTP = first to invent
Second to conceive + no due diligence on first inventor + first to RTP = first to invent
Abandon, suppress, or conceal
First inventor must have been diligent in bringing invention to public
Applying for patent
Taking steps necessary to make invention or product available to public
Does failure to file mean he abandoned, suppressed, or concealed?
Not necessarily
Bringing the invention or a product of the invention to market can avoid the finding
Determined by reasonable business practices
Resumption of activity prior to second inventor’s conception date
If the first inventor resumes work on reduction to practice before the second inventor’s conception date, can use the resumption of work date as his new invention date
Since before second inventor’s conception date, bars patent
Interference
Determine which is first and thus has priority
Statutory Bar
Critical date  one year prior to patent filing date
§102(b)
When is an invention in public use in this country?
Person other than inventor/applicant uses the invention in a way the invention intended to be used
Inventor’s private, personal use